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Publication Number: FHWA-HRT-04-096
Date: August 2005

Evaluation of LS-DYNA Wood Material Model 143

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Figure 1. LS-DYNA simulations of southern yellow pine showing brittle behavior in tension and shear, and ductile behavior in compression. Graphs, A, B, and C.

  1. Tension. This graph shows a blue line rising diagonally across the graph before sloping back down. The vertical axis of this graph ranges from 0 to 25,000 and represents Tensile Stress Parallel to Grain (psi) while the horizontal axis of this graph ranges from 0.0 to 1.5 and represents Tensile Strain Parallel to grain (percent). The blue line rises from the zero points on both axes diagonally across the graph peaking at the points of 26,000 on the vertical axis and just before 1.0 on the horizontal axis. From there, is begins to slope back down until it meets the horizontal axis at the points of zero on the vertical axis and 1.2 on the horizontal axis. This slope depicts Brittle Post-Peak Softening.

  2. Shear. This graph shows a blue line rising diagonally across half the graph before sloping back down toward the horizontal axis. The vertical axis of this graph ranges from 0 to 3,000 and represents Shear Stress Parallel to Grain (psi) while the horizontal axis ranges from 0 to 6 and represents Shear Strain Parallel to Grain (percent). The blue line rises from the points of zero on both axes diagonally, peaking at the points of 2,400 on the vertical axis and 2 on the horizontal axis. From there, it begins to gradually slope back down into the horizontal axis, where it leaves the graph at zero point on the vertical axis and 6 on the horizontal axis. This gradual slope depicts Moderate Post-Peak Softening.

  3. Compression. This graph shows a blue line rising across a quarter of the graph where it plateaus and from there, runs straight off the graph. The vertical axis of this graph ranges from 0 to 8,000 and represents Compressive Stress Parallel to grain (psi) while the horizontal axis of this graph ranges from 0.0 to 1.5 and represents Compressive Strain Parallel to Grain (percent). The blue line rises at a slight angle up the length of the graph where it peaks at the points of 7,400 on the vertical axis and 0.5 on the horizontal axis. The curve just before the blue line peaks, at the points of 6,400 on the vertical axis and 0.3 on the horizontal axis depicts Pre-Peak Hardening. From the peak, the blue line plateaus and runs straight off the graph at the points of 7,600 on the vertical axis and 1.5 on the horizontal axis. This plateau depicts No Post-Peak Softening.

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Figure 2. Good correlation between LS-DYNA simulations (dashed lines) and measured clear wood data (solid lines) for southern yellow pine in tension parallel to the grain. Graph.

This graph shows ten different lines, five dashed with respective twins solid in nature. The first line is red and depicts 4 percent MC. The second is yellow and depicts 8 percent MC. The third is green and depicts 12 percent MC. The fourth is blue and depicts 18 percent MC while the fifth is black and depicts Saturated. The vertical axis of this graph ranges from 0 to 150 and represents Stress (megapascals) while the horizontal axis of this graph ranges from 0.0 to 1.0 and represents Strain (percent). The red lines run nearly parallel diagonally across the graph, the solid red line stopping at the points of 110 on the vertical axis and 0.65 on the horizontal axis, while the dashed red continues to the points of 115 on the vertical axis and 0.7 on the horiztonal axis where it peaks and then gradually slopes back down to the horizontal axis. The yellow lines run nearly parallel, both to the points of 135 on the vertical axis and 0.85 on the horizontal axis, where the solid yellow line ends and the dashed yellow line gradually slopes back down to the horizontal axis. The green lines run nearly parallel to each other, though the solid green line runs higher on the graph’s plane than the dashed, stopping at the points of 145 on the vertical axis and 0.9 on the horizontal axis, while the green dashed line peaks at the points of 140 on the vertical axis and 0.925 on the horizontal axis and then gradually slopes back down to the horizontal axis. The blue lines run nearly parallel, with the solid blue line overextending the blue dashed line, stopping at the points of 130 on the vertical axis and 1.25 on the horizontal axis while the dashed blue line peaks at the points of 125 on the vertical axis and 0.875 on the horiztonal axis where it gradually slopes back down to the horiztonal axis. Finally, the black lines run parallel to each other for only a fraction, the solid black line curving while the dashed black runs straight across the graph. The solid black line curves to the points of 65 on the vertical axis and 0.865 on the horizontal axis while the dashed black line peaks at the points of 85 on the vertical axis and 0.665 on the horizontal axis where it gradually slopes back down to the horizontal line.

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Figure 3. Good correlation between LS-DYNA simulations (dashed lines) and measured clear wood data (solid line) for southern yellow pine in compression perpendicular to the grain. Graph.

This graph shows ten different lines, five solid, with respective twins dashed in nature. The first line is red and depicts 4 percent MC. The second is yellow and depicts 8 percent MC. The third is green and depicts 12 percent MC. The fourth is blue and depicts 18 percent MC while the fifth is black and depicts Saturated. The vertical axis of this graph ranges from 0 to 20 and represents Stress (megapascals) while the horizontal axis of this graph ranges from 0.0 to 4.0 and represents Strain (percent). The red lines run nearly parallel with each other rising with a curve until they plateau at the points of 14.5 on the vertical axis and 2.5 on the horizontal axis, where they run nearly straight off the graph. The yellow lines run nearly parallel with each other until they peak, the yellow dashed line at the points of 12.5 on the vertical axis and 2.05 on the horizontal axis where it plateaus and runs straight off the graph, while the yellow solid line peaks at the points of 13 on the vertical axis and 2.0 on the horizontal axis where it plateaus for a distance and stops at the points of 13 on the vertical axis and 3.5 on the horiztonal axis. The green lines run nearly parallel to each other, the solid line slightly shallower than the dashed as it rises in a gradual curve, peaking at the points of 10 on the vertical axis and 1.0 on the horiztonal axis where it plateaus and runs straight off the graph, while the solid green line gradually curves to a peak at the points of 10 on the vertical axis and 3.0 on the horizontal axis where it plateaus to an end at the points of 10 on the vertical axis and 3.7 on the horizontal axis. The blue lines run nearly parallel to each other, though the blue dashed line peaks first at the points of 6.5 on the vertical axis and 1.5 on the horizontal axis where it plateaus and runs straight off the graph while the solid blue line peaks at the points of 7 on the vertical axis and 2.7 on the horizontal axis and gradually slopes up where it leaves the graph and the points of 3 on the vertical axis and 4.0 on the horiztonal axis. Finally, the black line run nearly parallel, the solid black line slightly shallower than the black dashed line which peaks at 4 on the vertical axis and 1.5 on the horizontal axis where it plateaus and runs straight off the graph, while the solid black line begins at the points of zero, 0.0 and gradually curves just under the black dashed line until it meets it at the end of the graph at the points of 4 on the vertical axis and 4.0 on the horizontal axis.

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Figure 4. Schematic of FPL timber compression test setup. Diagram.

This figure shows an elongated rectangle, representing a piece of timber cross section, standing straight up on end. There are two darkened squares, one beneath the cross section and one resting on top that depict Steel end caps with the one at the top resting beneath a black cylindrical object depicting a Spherical Swiveling load head end cap. On any of the four sides of the cross section are five blackened squares each four small rollers attached to each and rest against the wood. These represent the Restraining cage with five roller supports per side (all four sides).

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Figure 5. These comparisons of the model with test data were used to set the hardening behavior of the southern yellow pine model in parallel-to-the-grain compression. Graphs A and B.

  1. Select Structural. This graph shows two distinct lines, one solid black, depicting Clear Wood Calculation and one broken black line depicting SEL STR Calculation. Both lines stand out against a background of other colored lines, mostly red, some green, some blue, sprawled sporadically behind the two black lines nearly covering the entire canvas behind the distinct two lines. The vertical axis of this graph ranges from 0 to 1,000 and represents Load (kilonewtons) while the horizontal axis ranges from 0 to 15 and represents Deflection (millimeters). The solid black line rises in a high arch across the graph from the points of zero vertical and horizontal axes until it plateaus for a measure at the points of 1,000 on the vertical axis and 13 on the horiztonal axis. The broken black line rises gradually from the points of zero on both the vertical and horizontal axes and peaks at the points of 500 on the vertical axis and 6.5 on the horizontal axis where it plateaus and finally stop at the points of 500 on the vertical axis and 10 on the horizontal axis.

  2. Grade 2. This graph shows two distinct lines, one solid black, depicting Clear Wood Calculation and one broken black line depicting SEL STR Calculation. Both lines stand out against a background of other colored lines, mostly red, some green, some blue, sprawled sporadically behind the two black lines nearly covering the entire canvas behind the distinct two lines. The vertical axis of this graph ranges from 0 to 1,000 and represents Load (kilonewtons) while the horizontal axis ranges from 0 to 15 and represents Deflection (millimeters). The solid black line rises in a high arch across the graph from the points of zero vertical and horizontal axes until it plateaus for a measure at the points of 1,000 on the vertical axis and 13 on the horiztonal axis. The broken black line rises gradually from the points of zero on both the vertical and horizontal axes and peaks at the points of 440 on the vertical axis and 6 on the horizontal axis where it plateaus and finally stops at the points of 440 on the vertical axis and 10 on the horizontal axis.

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Figure 6. These components of the model with the parallel to the grain timber bending test data demonstrate the need for different quality factors in tension and compression. Graphs.

Graph (a) SEL STR. This graph shows three distinct lines. The first line, solid and black is labeled Clear Wood. The second line, solid black with small dots is labeled SEL STR, Q subscript 1 equals 0.49 Q subscript c equals 0.49 Q subscript stiff equals 1.0. The third line, solid black with large diamonds is labeled SEL STR, Q subscript 1 equals 0.25 Q subscript c equals 0.49 Q subscript stiff equals 0.8. The vertical axis of this graph ranges from zero to twenty and represents Load (Kips) while the horizontal axis of this graph ranges from zero point zero to 2.5 and represents Deflection in inches.

The first line, solid black, begins at the point of zero on both axes where it ascends diagonally across the graph until it leaves the graph at the point of 16 on the vertical axis and 2.5 on the horizontal axis.

The second line, solid black with dots begins at the points of zero on both axes and ascends across the graph in an arch, leaving the graph at the point of 14 on the vertical axis and 2.5 on the horizontal axis.

The third line, solid black with large diamonds begins at the point of zero on both axes where it then ascends to the point of 8 on the vertical axis and 1.5 on the horizontal axis. From this point the line drops straight down and off of the graph. The line then re-enters the graph and oscillates between the points of 5 and zero on the vertical axis until it leaves the leaves the graph at 2 on the vertical axis and 2.5 on the horizontal axis.

Graph (b) Grade 2. This graph shows three distinct lines. The first line, solid and black is labeled Clear Wood. The second line, solid black with small dots is labeled SEL STR, Q subscript 1 equals 0.43 Q subscript c equals 0.43 Q subscript stiff equals 1.0. The third line, solid black with large diamonds is labeled SEL STR, Q subscript 1 equals 0.25 Q subscript c equals 0.43 Q subscript stiff equals 0.8. The vertical axis of this graph ranges from zero to twenty and represents Load (Kips) while the horizontal axis of this graph ranges from zero point zero to 2.5 and represents Deflection in inches.

The first line, solid black, begins at the point of zero on both axes where it ascends diagonally across the graph until it leaves the graph at the point of 16 on the vertical axis and 2.5 on the horizontal axis.

The second line, solid black with dots begins at the points of zero on both axes and ascends across the graph in an arch, leaving the graph at the point of 14 on the vertical axis and 2.5 on the horizontal axis.

The third line, solid black with large diamonds begins at the point of zero on both axes where it then ascends to the point of 8 on the vertical axis and 1.5 on the horizontal axis. From this point the line drops straight down and off of the graph. The line then re-enters the graph and oscillates between the points of 4 and zero on the vertical axis until it leaves the leaves the graph at 4 on the vertical axis and 2.5 on the horizontal axis.

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Figure 7. Quasi-static post test setup. Photo.

This photo shows a cross section of timber lying on its side on a concrete surface. The piece of timber is fastened inside a steel frame, with four cross bars bolted across the top to hold the timber in place, while the apparatus itself is bolted directly to the concrete floor. A pulley system is rigged across the floor a ways, itself bolted into a concrete wall. From the wall emerges a long hydrolytic looking apparatus. To this apparatus is fastened a long steel cable, which itself is fasted to a large pulley, which in turn is fasted to an even larger hook. This hook is threaded through the eye of a large bolt, which has been drilled into the top half of the piece of timber and fasted through the other side. It would appear the hydraulic pulls the steel cable through the pulley, in turn pulling on the eye threaded through the timber until the timber snaps.

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Figure 8. Details for the rigid frame used in the quasi-static post test setup. Photos A and B.

  • Steel at bottom of support. This photo shows a cross section of timber fastened inside a steel frame lying on its side, long way in the picture, with four cross bars bolted across the top to hold the timber in place, on a concrete surface. The piece of timber is fastened inside a steel frame, with four cross bars bolted across the top to hold the timber in place, while the apparatus itself is bolted directly to the concrete floor. The right hand side of the frame has several small sheets of steel clamped in place between the piece of timber and the right hand bottom side of the frame itself. The eye-hook, which is fastened through the top of the timber, is clearly visible, with the pulley and hook attached.

  • Neoprene at top of support on compression side. This photo shows a close up of a cross section of timber fastened inside a steel frame, which in turn is fastened to a concrete surface. Only three of the four cross bars are visible in this closeup. A piece of neoprene is wedged between the timber and the right hand upper side of the steel frame on the compression side.

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Figure 9. Deformed configuration of posts in static tests. Photos A and B.

  • DS-65 Test 1420. This photo shows a cross section piece of timber fastened inside a steel frame, lying lengthwise from top to bottom on a concrete surface. The steel frame itself is fastened to the concrete surface, and four cross bar are bolted across the top of the piece of timber holding it in its place. There exists an eye-hook run through the top of the timber with a pulley cable and hook attached to this eye-hook. The timber has split along the length of its grain, down its center and has cracked along its left-hand side as the right hand side of the timber was being forced against the steel frame.

  • Grade 1 Test 418. This photo shows a cross section piece of timber fastened inside a steel frame, lying lengthwise at a slight angle from top to bottom on a concrete surface. The steel frame itself is fastened to the concrete surface, and four cross bar are bolted across the top of the piece of timber holding it in its place. There exists an eye-hook run through the top of the timber with a pulley cable and hook attached to this eye-hook. The timber has split along its left-hand side severely as the right hand side of the timber was forced against the steel frame.

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Figure 10. Deformed configuration of posts in static tests. Photos A and B.

  • DS-65 post. This photo shows a closeup of a cross section of timber fastened in a steel frame, which in turn is fastened to a concrete surface. Two of the four cross bars are visible in this closeup. The timber has snapped, the cracking beginning between the first and second cross bar moving in a diagonal fashion three quarters of the way through the width of the beam.

  • Grade 1D post. This photo shows a closeup of a cross section of timber fastened in a steel frame, which in turn is fastened to a concrete surface. Only one of the four cross bars are visible in this closeup. The fracture begins and remains nearly parallel with the visible cross bar, splitting the timber straight across the width of the beam.

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Figure 11. Measured load-deflection histories exhibit sudden drops in force as the post fails in the tensile region. Graph.

This graph shows two distinct lines, the first colored red and labeled Test 418, Grade 1 and the second colored blue and labeled Test 1420, DS-65. The vertical axis of this graph ranges from 0 to 80 and represents Force (kilonewtons) while the horizontal axis ranges from 0 to 250 and represents Deflection (millimeters). Both lines begin at the points of zero on the vertical and horizontal axes.

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Figure 12. Quasi-static (blue) and dynamic (pink) performance envelopes developed and plotted by the user. Graphs A, B, C, and D.

All four graphs show four distinct lines. The first two lines in each graph are solid blue and are labeled Static while the other two lines are pink dashed and labeled Dynamic.

  1. This graph shows four distinct lines. The first two are solid blue and are labeled Static while the last two are dotted pink and are labeled Dynamic. This vertical axis of this first graph ranges from 0 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection (millimeters). The vertical axis of this graph ranges from zero to 100 and represents Force (kilonewtons) while the horizontal axis ranges from zero to 180 and represents Deflection in millimeters. All four lines begin at the points of zero on both axes. The first blue line rises in a wide arc from the point of zero and ascends to the point of 80 on the vertical axis and 60 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 30 on the vertical axis and 180 on the horizontal axis. The second blue line rises in a wide arc from the point of zero and ascends to the point of 68 on the vertical axis and 60 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 20 on the vertical axis and 180 on the horizontal axis. The first pink dotted line rises from its starting point in one large arc, peaking at the point of 92 on the vertical axis and 80 on the horizontal axis before descending to the point of zero on the vertical axis and 160on the horizontal axis where it comes to an end. The first pink dotted line rises from its starting point in one large arc, peaking at the point of 70 on the vertical axis and 80 on the horizontal axis before descending to the point of zero on the vertical axis and 145on the horizontal axis where it comes to an end.

  2. This graph shows four distinct lines. The first two are solid blue and are labeled Static while the last two are dotted pink and are labeled Dynamic.This vertical axis of this first graph ranges from 0 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection (millimeters). The vertical axis of this graph ranges from zero to 100 and represents Force (kilonewtons) while the horizontal axis ranges from zero to 180 and represents Deflection in millimeters. All four lines begin at the points of zero on both axes. The first blue line rises in a small arc from the point of zero and ascends to the point of 56 on the vertical axis and 44 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 10 on the vertical axis and 180 on the horizontal axis. The second blue line rises in a wide arc from the point of zero and ascends to the point of 48 on the vertical axis and 40 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 6 on the vertical axis and 180 on the horizontal axis. The first pink dotted line rises from its starting point in one wide arc, peaking at the point of 54 on the vertical axis and 90 on the horizontal axis before descending to the point of zero on the vertical axis and 162on the horizontal axis where it comes to an end. The first pink dotted line rises from its starting point in one large arc, peaking at the point of 44 on the vertical axis and 80 on the horizontal axis before descending to the point of zero on the vertical axis and 140 on the horizontal axis where it comes to an end.

  3. This graph shows four distinct lines. The first two are solid blue and are labeled Static while the last two are dotted pink and are labeled Dynamic. The vertical axis of this graph ranges from 0 to 10000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection. All four lines begin at the points of zero on both the vertical and horizontal axis. The first blue line slopes upwards and off the graph at the points of 8200 on the vertical axis and 180 on the horizontal axis. The second blue line slopes upwards and off the graph at the points of 7500 on the vertical axis and 180 on the horizontal axis. The first pink dotted line slopes upward to the points of 8000 on the vertical axis and 160 on the horizontal axis where it comes to an end. The second dotted pink line slopes upward to the points 6400 on the vertical axis and 160 on the horizontal axis where it too comes to an end.

  4. This graph shows four distinct lines. The first two are solid blue and are labeled Static while the last two are dotted pink and are labeled Dynamic. The vertical axis of this graph ranges from 0 to 10000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection. All four lines begin at the points of zero on both the vertical and horizontal axis. The first blue line slopes upwards and off the graph at the points of 4400 on the vertical axis and 180 on the horizontal axis. The second blue line slopes upwards and off the graph at the points of 400 on the vertical axis and 180 on the horizontal axis. The first pink dotted line slopes upward to the points of 5000 on the vertical axis and 160 on the horizontal axis where it comes to an end. The second dotted pink line slopes upward to the points 400 on the vertical axis and 160 on the horizontal axis where it too comes to an end.

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Figure 13. Grade 1 and 1D static post test measurements exhibit substantial scatter. Graph A and B.

Graph A (Force versus deflection)

These graphs show 15 test data curves, with seven curves (Tests 712, 563, 113, 1223, 223, 1063, and 1019) on the first graph and eight curves (Tests 1201, 1124, 1073, 308, 718, 1323, 652, and 418) on the second graph.  The x-axes are deflection in inches between 0 and 10 (0 and 254 mm).  The y-axes are force in kips between 0 and 20 kips (0 and 90 kN).  On the first graph, four curves (563, 113, 1223, 223) increase in force from 0 to between  9.5 and 11.5 kips over 1.3 inches in deflection, followed by sudden drop in force indicative of sudden post failure (as well as gage failure).  The fifth curve increases in force from 0 to 12.5 kips over 1.8 inches, followed by sudden failure.  The remaining two curves exhibit a more ductile behavior.  One curve (1019) reaches a peak force of approximately 12.5 kips in two inches, then maintains that force until 3.1 inches, followed by a gradual reduction in strength to 4 kips at 8 inches.  The other curve (712) reaches a peak force of approximately 16 kips in 3 inches, then maintains that force until 4.4 inches, followed by sudden failure. On the second graph, three curves (1201, 718, and 1124) increase in force from 0 to about 9 kips over 1.3 to 1.5  inches in deflection, followed by sudden drop in force indicative of sudden post failure.  Two curves (1323 and 652) increases in force from 0 to 10 kips over 1.5 inches, followed by a more gradual increase in force to 11 kips by 2.7 inches, followed by sudden failure. One curve (418) increases in force from 0 to 13.2 kips in 1.9 inches followed by sudden failure. The remaining two curves exhibit a more ductile behavior.  One curve (1201) reaches a peak force of approximately 8 kips in two inches, then maintains that force until 4.3 inches, followed by failure.  The other curve (1073) reaches a peak force of approximately 5 kips in 1.5 inches, then maintains that force until 4.3 inches, followed by gradual failure.

Graph B (Energy versus deflection).

These graphs show 15 test data curves, with seven curves (Tests 712, 563, 113, 1223, 223, 1063, and 1019) on the first graph and eight curves (Tests 1201, 1124, 1073, 308, 718, 1323, 652, and 418) on the second graph.  The x-axes are deflection in inches between 0 and 10 (0 and 254 mm).  The y-axes are energy in kip-inches between 0 and 100 kip-inches  (0 and 11,300 kN-mm).  These curves represent the area under the force-deflection curves just discussed.  All curves show a steep increase in energy over about the first 5-inches of deflection, followed by a more gradual increase over the 10 inches of the graph. On the first graph, curve 712 increases from 0 to 58 kip-inches in 5 inches and 63 kip-inches in 9.2 inches. Curve 563 increases from 0 to 20 kip-inches in 4 inches and 21 kip-inches in 9 inches. Curve 113 increases from 0 to 10 kip-inches in 1.5 inches and 15 kip-inches in 10 inches. Curve 1223 increases from 0 to 20 kip-inches in 4 inches and 28 kip-inches in 10 inches. Curve 223 increases from 0 to 33 kip-inches in 5 inches and 43 kip-inches in 8.8 inches. Curve 1063 increases from 0 to 21 kip-inches in 4 inches and 42 kip-inches in 9.7 inches. Curve 1019 increases from 0 to 40 kip-inches in 4 inches and 61 kip-inches in 8.3 inches. On the second graph, curve 1201 increases from 0 to 31 kip-inches in 4.6 inches. Curve 1124 increases from 0 to 29 kip-inches in 4.2 inches and 39 kip-inches in 9.2 inches. Curve 1073 increases from 0 to 22 kip-inches in 5 inches and 34 kip-inches in 9.2 inches. Curve 308 increases from 0 to 37 kip-inches in 5 inches and 42 kip-inches in 10 inches. Curve 718 increases from 0 to 17 kip-inches in 4 inches and 28 kip-iinches in 8.6 inches. Curve 1323 increases from 0 to 28 kip-inches in 3.5 inches and 29 kip-inches in 10 inches. Curve 652 increases from 0 to 10 kip-inches in 2 inches and 18 kip-inches in 10 inches. Curve 418 increases from 0 to 18 kip-inches in 4 inches and 37 kip-inches in 9.2 inches.

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Figure 14. Good correlations between the LS-DYNA calculations and quasi-static performance envelopes determine the default quality factors for Grade 1 southern yellow pine of Q subscript T equals 0.47 with Q subscript C equals 0.63. Graphs A and B.

  1. This first graph A shows force versus deflection in four distinct lines. The first line is solid black and is labeled LS-DYNA calculation. The second line is dotted blue and is labeled Grade 1 Test 418. Finally, the last two lines are solid blue and are labeled Performance Envelopes. The vertical axis of this graph ranges from 0 to 60 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid black line ascends to the points of 45 on the vertical axis and 50 on the horizontal axis. It begins a steep descent at 70 and drops straight down at 90 on the horizontal axis to 6 on the vertical axis. After a few small peaks, it levels off at 8 on the vertical axis and leaves the graph at around 6. The dotted blue line follows a very similar pattern, but leaves the graph at 10 on the vertical axes. The first solid blue lines ascends the highest of the lines to 55 on the vertical axis at 50 on the horizontal axis. Its descent is slightly erratic but dropping suddenly like the other lines at 90 on the horizontal axis, but begins a more gradual descent at 28 on the vertical axis, eventually leaving the chart at 12 on the vertical axis. The second solid blue has the same ascent pattern as the other lines, but rises only to 45. Its precipitous drop comes sooner than the other three lines at 50 on the horizontal axis. The line is erratic between 55 and 100 on the horizontal axis where after a slight rise, it drops again at 155 on the horizontal axis to about 2 on the vertical axis and leaves the graph.

  2. This second graph B shows energy versus deflection in four distinct lines. The first line is solid black and is labeled LS-DYNA calculation. The second line is dotted blue and is labeled Grade 1 Test 418. Finally, the last two lines are solid blue and are labeled Performance Envelopes. The vertical axis of this graph ranges from 500 to 5,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid black line slopes upwards and off the graph at the points of 4,600 on the vertical axis and 200 on the horizontal axis. The dotted blue line slopes upwards and off the graph to the points of 4,000 on the vertical axis and 200 on the horizontal axis. The first solid blue lines slopes upwards and off the graph at the points of 4,500 on the vertical axis and 200 on the horizontal axis, while the second solid blue line slopes upwards and off the graph at the points of 4,000 on the vertical axis and 200 on the horizontal axis.

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Figure 15. Good correlations between the LS-DYNA calculations and quasi-static performance envelopes determine the default quality factors for DS-65 southern yellow pine of Q subscript T equals 0.80 with Q subscript C equals 0.93. Graphs A and B.

  1. The first graph A shows force versus deflection. The first line is solid black and is labeled LS-DYNA calculation. The second line is dotted blue and is labeled DS-65 test 1420. Finally, the last two lines are solid blue and are labeled Performance Envelopes. The vertical axis of this graph ranges from 0 to 100 and represents Force (kilonewton) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. All lines ascend steeply to a range of 70 to 75 kilonewtons in force at a range of 50 to 85 millimeters of deflection. The solid black line drops off steeply at 85 kilonewtons and descends with only a few shallow spikes to low of 14 kilonewtons at 55 millimeters. It rises slightly to 20 kilonewtons and leaves the chart. The dotted blue line rises to 70 kilonewtons at 70 millimeters. It too begins a gradual descent to 46 kilonewtons at 130 millimeters and stops. The first solid blue line stays at 80 kilonewtons from 50 to 100 millimeters. It then drops quickly to 50 kilonewtons with 48 millimeters of deflection. The line then gradually ascends, leaving the graph at 30 kilonewtons. The second sold blue line peaks at 65 kilonewtons and 70 millimeters. It drops sharply to 30 kilonewtons at 100 millimeters. The line drops gradually to 20 kilonewtons where it leaves the chart.

  2. The second graph B shows four distinct lines. The first line is solid black and is labeled LS-DYNA calculation. The second line is dotted blue and is labeled DS-65 test 1420. Finally, the last two lines are solid blue and are labeled Performance Envelopes. The vertical axis of this graph ranges from 0 to 9,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid black line slopes upwards and off the graph at the points of 8,000 on the vertical axis and 200 on the horizontal axis. The dotted blue line slopes upwards to the points of 6,000 on the vertical axis and 130 on the horizontal axis where it comes to an end. The first solid blue lines slopes upwards and off the graph at the points of 8,500 on the vertical axis and 200 on the horizontal axis, while the second solid blue line slopes upwards and off the graph at the points of 7,400 on the vertical axis and 200 on the horizontal axis.

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Figure 16. The parallel-to-the-grain post fracture calculated in the post just below the top of the rigid support is in agreement with the location of damage observed in the tests. Diagrams A, B, C, and D.

  1. Grade 1 deformed configuration. This figure shows a computer-generated illustration of a post. The post is shown inserted in the metal brace. The post itself is colored red while the metal brace is colored green. Near the top of the post appears a small section colored purple with an eyehook protruding from the structure. The top half of the post leans to the right at a rough twenty-degree angle, forming a gap near the entry point into the brace. The gap itself spreads through nearly three-quarters the width of the post.

  2. Fringes of damage. This figure shows a computer-generated illustration of a post. The post is colored white in this illustration, and an eyehook appears from the right hand side of the structure near its top. The top half of the post leans to the right at a rough twenty-degree angle, forming a gap near the entry point into the brace. The gap itself spreads through nearly three-quarters the width of the post. The fringes of damage are colored blue and red and appear on the underside of the gap for a short length and at the point in which the top and bottom halves of the post are still connected.

  3. DS-65 deformed configuration. This figure shows a computer-generated illustration of a post. The post is shown inserted in the metal brace. The post itself is colored red while the metal brace is colored green. Near the top of the post appears a small section colored purple with an eyehook protruding from the structure. The top half of the post leans to the right at a rough twenty-degree angle, forming a gap near the entry point into the brace. The gap itself spreads through only a quarter the width of the post.

  4. Fringes of damage. This figure shows a computer-generated illustration of a post. The post is colored white in this illustration, and an eyehook appears from the right hand side of the structure near its top. The top half of the post leans to the right at a rough twenty-degree angle, forming a gap near the entry point into the brace. The gap itself spreads through only a quarter the width of the post. The fringes of damage are colored blue and red and appear on the underside of the gap for a short length and on the upper side of the gap nearer the front of the gap.

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Figure 17. Three geometric models were set up for performing parametric calculations. Diagrams A, B, and C.

  1. Fixed nodes. This figure shows a computer-generated illustration of a post. The bottom half of the post is colored a light green. A small section just above bottom half is colored red and the remaining top quarter of the post is colored a dark purple and shows an arrow pointing into the right hand side of the structure with a label that reads Applied Velocity. A not to the left-hand side of the structure and beneath the structure both read No X or Z displacement.

  2. Rigid walls. This figure shows a computer-generated illustration of a post. The post itself is colored a dark red. A small section near the top of the post is colored purple and shows an eyehook protruding from the left-hand side. Two green sleeves are also shown running up either side of the post for half of the structure's length

  3. Full support structure. This figure shows a computer-generated illustration of a post. The post itself is colored a dark red. A small section near the top of the post is colored purple and shows an eyehook protruding from the left-hand side. The post is shown inserted in a metal brace, which runs up either side of the structure and shows three crossbars holding the brace in place. The brace itself is colored a dark green.

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Figure 18. The force-deflection curve calculated with the fast-running, rigid-wall model is similar to that calculated with the full-support structure, making it useful for performing parametric calculations. Graphs A and B.

  1. Force-deflection. This graph shows three distinct lines. The first line is solid red and is labeled Rigid Walls. The second line is solid black and is labeled Full Support Structure. The third and final line is dotted blue and is labeled Grade 1 test 418. The vertical axis of this graph ranges from 0 to 60 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection (millimeters). All three lines begin at the points of zero on both the vertical and horizontal axes. The first line, the red line, rises in at a slope to the point of 48 on the vertical axis and 50 on the horizontal axis. From this point the red line drops significantly to the point of 20 on the vertical axis and 85 on the horizontal axis where it then descends unevenly across the remainder of the graph until it leaves at the points of 6 on the vertical axis and 180 on the horizontal axis. The second line, solid black rises in at a slope to the point of 48 on the vertical axis and 50 on the horizontal axis. From this point the black line drops significantly to the point of 14 on the vertical axis and 85 on the horizontal axis where it then descends unevenly across the remainder of the graph until it leaves at the points of 4 on the vertical axis and 180 on the horizontal axis. The third line, dotted blue, rises in at a slope to the point of 48 on the vertical axis and 50 on the horizontal axis. From this point the blue line drops significantly to the point of 8 on the vertical axis and 85 on the horizontal axis where it then spikes diagonally to the point of 14 on the vertical axis and 110 on the horizontal axis. From this point the line then descends gradually in a near straight line until it leaves the graph at the point of 8 on the vertical axis and 180 on the horizontal axis.

  2. Energy-deflection. This graph shows three distinct lines. The first line is solid red and is labeled Rigid Walls. The second line is solid black and is labeled Full Support Structure. The third and final line is dotted blue and is labeled Grade 1 test 418. The vertical axis of this graph ranges from 0 to 5,000 and represents energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All three lines begin at the points of zero on both the vertical and horizontal axes. The solid red line slows upwards and off the graph at the points of 4,400 on the vertical axis and 200 on the horizontal axis. The solid black line slopes upwards and off the graph at the points 4,200 on the vertical axis and 200 on the horizontal axis. Finally, the dotted blue line slopes upwards and off the graph at the points of 4,000 on he vertical axis and 200 on the horizontal axis.

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Figure 19. Pinning a truss to the bolt to simulate the vertical force applied by the pulley system, increases the peak force by about 4 percent. Graph and Diagram.

Graph. (a) Load-deflection comparisons.

This graph shows two distinct lines. The first line is solid blue and is labeled Without Truss while the second line is colored red and is labeled With Truss. The vertical axis of this graph ranges from zero to 100 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Deflection in millimeters. Both lines begin at the point of zero on both the vertical and horizontal axes. The first line, the blue line, rises to the point of 65 on the vertical axis and 70 on the horizontal axis where it then drops to the point of 38 on the vertical axis and 110 on the horizontal axis. The blue then continues to descend unevenly until it comes to a stop at the points of 20 on the vertical axis and 190 on the horizontal axis. The second line, the red line, rises to the point of 65 on the vertical axis and 70 on the horizontal axis where it then drops to the point of 40 on the vertical axis and 110 on the horizontal axis. The blue then continues to descend unevenly until it leaves the graph at the points of 24 on the vertical axis and 200 on the horizontal axis.

Diagram (b) rigid wall mesh with truss.

This figure shows a computer-generated illustration of a post, colored red with a small section near the top colored purple. An eyehook is shown protruding from the left-hand side of the post. The top half of the post leans to the left at a rough fifteen-degree angle. A small gap is shown forming near the lower half of the post.

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Figure 20. The peak force increases with the applied velocity until convergence is attained at 0.25 millimeters per second. Graph.

This graph shows two distinct lines. The first line is solid blue and is labeled 1.00 Miles per second while the second line is colored red and is labeled 0.25 Miles per second. The vertical axis of this graph ranges from zero to 100 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 180 and represents Deflection in millimeters. Both lines begin at the point of zero on both the vertical and horizontal axes. The first line, the blue line, rises to the point of 75 on the vertical axis and 70 on the horizontal axis where it then drops to the point of 48 on the vertical axis and 70 on the horizontal axis. The blue line then continues to descend unevenly to the point of 32 on the vertical axis and 100 on the horizontal axis where it then ascends gradually and leaves the graph at the points of 50 on the vertical axis and 180 on the horizontal axis. The second line, the red line, rises to the point of 75 on the vertical axis and 70 on the horizontal axis where it then drops to the point of 48 on the vertical axis and 74 on the horizontal axis. The blue line then continues to descend unevenly to the point of 32 on the vertical axis and 108 on the horizontal axis where it then ascends gradually and leaves the graph at the points of 50 on the vertical axis and 180 on the horizontal axis.

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Figure 21. The peak force increases with the applied velocity until convergence is attained at 0.25 millimeters per second. Graph.

This graph shows two distinct lines. The first line is colored red and is labeled Not Filtered while the second line is colored blue and is labeled Filtered at 60 HZ. The vertical axis of this graph ranges from zero to 100 and represents Force in kilonewtons while the horizontal axis of this graph ranges zero to 100 and represents Deflection in millimeters. The first line, the red line rises from the point of zero on both axes to the point of 65 on the vertical axis 60 on the horizontal axis. From this point the line oscillates heavily between the points of 65 and zero on the vertical axis until the line comes to an end at the points of 25 on the vertical axis and 95 on the horizontal axis. The second line, the blue line, ascends from the point of zero on both axes to the point of 65 on the vertical axis 60 on the horizontal axis. From this point the line descends to the point of 28 on the vertical axis and 65 on the horizontal axis where it runs in a wave across the graph until it comes to a stop at the points of 25 on the vertical axis and 95 on the horizontal axis.

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Figure 22. The energy required to break the post increases as the value of the parallel-to-the-grain fracture energy increases. Graph.

This graph shows two distinct lines. The first is a solid green line with green dots and is labeled G subscript F perp equals 50 G subscript F para while the second is solid red and is labeled G subscript F perp equals 250 G subscript F para. The vertical axis of this graph ranges from 0 to 60 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). Both lines start at the points of zero on the vertical and horizontal axes. The green line mirrors the red line as they both spike upward. The green line falls away from the red as it peaks at the points of 45 on the vertical axis and 30 on the horizontal axis, where it drops straight down to the points of 13 on the vertical axis and 13 on the horizontal axis. From there the green line spikes again in the slightest to the points of 19 on the vertical axis and 45 on the horizontal axis where it slopes downward in the least to its end at the points of 15 on the vertical axis and 115 on the horizontal axis. The red line continues its arch up and over the first green line peak where it peaks, itself, at the points of 49 on the vertical axis and 50 on the horizontal axis. From there the red line makes a sporadic drop, and plateaus at the points of 13 on the vertical axis and 105 on the horizontal axis for some time before dropping off again where it leaves the graph at the points of 5 on the vertical axis and 200 on the horizontal axis.

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Figure 23. Calculations with Q subscript C greater than Q subscript T soften more rapidly than calculations with Q subscript C equals Q subscript T. Graphs A and B.

Both graphs show three distinct lines. The first is a solid green line with green dots and is labeled Q subscript T equals 0.60 Q subscript C equals 0.60. The second line is solid red and is labeled Q subscript T equals 0.47 Q subscript C equals 0.63. Finally, the third line is blue dashed and is labeled Grade 1 Test 418.

  1. The vertical axis of this graph ranges from 0 to 60 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All three lines start at the points of zero on the vertical and horizontal axes. Both the red and green lines run on top of one another as they curve upward and peak at the points of 49 on the vertical axis and 50 on the horizontal axis. From there the green line stretches out beyond the red line to the points of 49 on the vertical axis and 70 on the horizontal axis where it drops off to the points of 40 vertical and 75 horizontal. The green line then curves downward gradually to the points of 19 on the vertical axis and 115 on the horizontal axis where it spikes back up in the slightest to the points of 23 vertical and 125 horizontal. From this point the green line gradually climbs linear off of the graph at the points of 25 vertical and 200 horizontal. The red line falls off sooner than the green at the points of 49 on the vertical axis and 65 on the horizontal axis where it continues to drop off steeply to the points of 12 on the vertical axis and 100 on the horizontal axis. From there the red line plateaus for some time before dropping off again at the points of 12 on the vertical axis and 145 on the horizontal axis where it slopes off of the graph at the points of 5 on the vertical axis and 200 on the horizontal axis. The blue dashed line rises in a gradually curve from the points of zero on both axes and peaks at the points of 46 on the vertical axis and 50 on the horizontal axis. The line then plateaus jaggedly until it begins to gradually drop off from the points of 46 on the vertical axis and 65 on the horizontal axis. From the points of 35 on the vertical axis and 85 on the horizontal axis the dashed blue line plummets severely, straight down to the points of 6 on the vertical axis and 90 on the horizontal axis. From there the blue line jolts back up to the points of 14 on the vertical axis and 115 on the horizontal axis where the line descends diagonally off the graph at the points of 6 on the vertical axis and 200 on the horizontal axis.

  2. The vertical axis of this graph ranges from 0 to 7,000 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). Both the red and green lines run one on top of the other as they ascend from the zero points on both the vertical and horizontal axes. At the points of 3,300 on the vertical axis and 75 on the horizontal axis the two lines split as the green line continues to ascend at a steeper rate until it leaves the graph at the points of 6,000 on the vertical axis and 200 on the horizontal axis while the red line gradually climbs off of the graph at the points of 4,200 on the vertical axis and 200 on the horizontal axis. The blue line begins at the points of zero on both the vertical and horizontal axes and mirrors the red and green lines as it climbs to its peak just beneath the other two lines. The blue line reaches a distinct peak at the points of 3,200 on the vertical axis and 85 on the horizontal axis where it continues a diagonal climb off the graph at the points of 3,900 on the vertical axis and 200 on the horizontal axis.

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Figure 24. The calculated peak force increases with increasing values of the softening parameter B. Graph.

This graph shows three distinct lines. The first line is solid red and is labeled B equals 1, while the second line is solid green and is labeled B equals 10. Finally, the third line is solid blue and is labeled B equals 100. The vertical axis of this graph ranges from 0 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 120 and represents Deflection (millimeters). All three lines run one on top of the other as they curve upward from the points of zero on the vertical and horizontal axes until the blue line surpasses the others at the points of 69 on the vertical axis and 60 on the horizontal axis where it continues its climb to the points of 84 on the vertical axis and 109 on the horizontal axis. From there the blue line dips down to the points of 78 on the vertical axis and 114 on the horizontal axis where it spikes again, off the graph at the points of 70 on the vertical axis and 120 on the horizontal axis. The red line shallows out from the point it breaks from the blue line and peaks at the points of 74 on the vertical axis and 82 on the horizontal axis. From there it slopes downward and unevenly plateaus until it leaves the graph at the points of 64 on the vertical axis and 120 on the horizontal axis. From the point at which the green line breaks from the blue line, it climbs slightly more to peak at the points of 76 on the vertical axis and 78 on the horizontal axis. From there the green line slopes downward, and plateaus at the points of 64 on the vertical axis and 92 on the horizontal axis before it drops off again where it runs off the graph at the points of 60 on the vertical axis and 120 on the horizontal axis.

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Figure 25. The softening parameter B determines the shape of the softening curve in these single element simulations for tension parallel to the grain. Graph.

This graph shows four distinct lines. The first is a solid red line and is labeled B equals 1 while the second is a solid green line and is labeled B equals 10. The third line is solid yellow and is labeled B equals 30 and finally the fourth line is solid blue and is labeled B equals 100. The vertical axis of this graph ranges from 0 to 90 and represents Stress (megapascals) while the horizontal line of this graph ranges from 0.0 to 5.0 and represents Strain (percent). All four lines rise up from the zero points on the vertical and horizontal axes at a steep grade to the points of 86 on the vertical axis and 0.7 on the horizontal axis. From there the four lines separate as the red line curves downward while the other three lines slope downward at various degrees, creating a streamer effect. All four lines cross each other at the points of 30 on the vertical axis and 2.9 on the horizontal axis before sloping off the graph. The red line leaves the graph at the points of 10 on the vertical axis at 5.0 on the horizontal while the green line leaves the graph at the points of 2 on the vertical axis and 5.0 on the horizontal axis. The yellow line leaves the graph at the points of just below 1 on the vertical axis and 5.0 on the horizontal axis and the blue line eaves the graph at the points of zero on the vertical axis and 5.0 on the horizontal axis.

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Figure 26. Type 4 stiffness control reduces hourglassing better than type 3 viscous control. Diagrams A and B.

  1. 120-millimeter deflection, Viscous control.

    This figure shows a closeup of a rectangular structure. The surface of this structure is broken down into rows and columns of small squares. The structure is roughly 18 rows high and eight columns wide. The top and bottom halves of the entire structure are colored a dull pink while the center of the structure is colored a dark red. The top half of the structure is tipped backward slightly, the first two squares in the first two columns at about the center point of the structure are missing, the remaining row of squares at center point squished as a result of the tipping top.120-millimeter deflection, Stiffness control. This figure shows a closeup of a rectangular structure. The surface of this structure is broken down into rows and columns of small squares. The structure is roughly 18 rows high and eight columns wide. The top and bottom halves of the entire structure are colored a dull pink while the center of the structure is colored a dark red. The top half of the structure is tipped backward slightly, the first four squares in the first four columns at about the center point of the structure are missing, the remaining row of squares at center point squished as a result of the tipping top.

    120-millimeter deflection, Fully integrated S/R.

    This figure shows a closeup of a rectangular structure. The surface of this structure is broken down into rows and columns of small squares. The structure is roughly 18 rows high and eight columns wide. The top and bottom halves of the entire structure are colored a dull pink while the center of the structure is colored a dark red. The top half of the structure is tipped backward slightly, the first four squares in the first four columns at about the center point of the structure are missing, the remaining row of squares at center point squished as a result of the tipping top.

    190-millimeter deflection, Viscous control.

    This figure shows a rectangular structure broken into rows and columns of small squares. The structure is roughly 42 rows high and eight columns wide. The majority of the structure is colored a dull pink with the exception of eight by six section colored in dark purple with an eye hook protruding from the right hand side and an eight by eleven section at the very bottom of the structure colored a dark red. Row six in the red section of the rectangle is missing its first two squares on the left hand side, while the next two squares are jagged and rough. The remaining squares in that row are squished as the top of the rectangle is tilted to the right, tearing those two squares from their original state.

    190-millimeter deflection, Stiffness control.

    This figure shows a rectangular structure broken into rows and columns of small squares. The structure is roughly 42 rows high and eight columns wide. The majority of the structure is colored a dull pink with the exception of eight by six section colored in dark purple with an eye hook protruding from the right hand side and an eight by eleven section at the very bottom of the structure colored a dark red. Row six in the red section of the rectangle is missing its first five squares on the left hand side, while the remaining three in that row are squished as the top of the rectangle is tilted to the right, tearing those two squares from their original state.

    190-millimeter deflection, fully integrated S/R.

    This figure shows a rectangular structure broken into rows and columns of small squares. The structure is roughly 42 rows high and eight columns wide. The majority of the structure is colored a dull pink with the exception of eight by six section colored in dark purple with an eye hook protruding from the right hand side and an eight by eleven section at the very bottom of the structure colored a dark red. The first five squares in row six of the red section have torn away from the squares that sat upon while the following three squares one row down have torn away from the squares they once sat on as the top of the rectangle tilts to the right.

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Figure 27. The peak force calculated with type 4 stiffness control agrees with the fully integrated element calculation better than the type 3 viscous calculation. Graph.

This graph shows three distinct lines. The first line is solid green and is labeled Viscous Hourglass Control while the second line is solid blue and is labeled Stiffness Hourglass Control. Finally, the third line is solid red and is labeled Fully Integrated Elements. The vertical axis of this graph ranges from 0 to 60 and represents force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All three lines curve upwards, one overlapping the other until the points of 45 on the vertical axis and 20 on the horizontal axis where the green line splits from the other two and runs slightly shallower. The green line breaks free from the other two, peaks and plateaus at the points of 47 on the vertical axis and 25 on the horizontal axis before it drops off, sloping down sporadically to the points of 24 on the vertical axis and 110 on the horizontal axis, where it jaggedly plateaus to the points of 24 on the vertical axis and 150 on the horizontal axis. From there the green line drops down drastically to the points of 13 on the vertical axis and 150 on the horizontal axis where it plateaus and runs in a wave off the graph. The red and blue lines continue to rise shortly after their split from the green line and peak at the points of 48 on the vertical axis and 150 on the horizontal axis. Both lines drop off and slope downward sporadically. The blue line stops and plateaus at the points of 13 on the vertical axis and 100 on the horizontal axis for some time before it drops off again to the points of 5 on the vertical axis and 150 on the horizontal axis where the blue line runs in a wave off the graph. The red line stops and plateaus at the points of 12 on the vertical axis and 110 on the horizontal axis before it too drops off again to the points of zero on the vertical axis and 165 on the horizontal axis where it runs straight off the graph.

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Figure 28. Less final hourglass energy is calculated with type 4 stiffness control than with type 3 viscous control. Graph.

This graph shows two distinct lines. The first is a solid green line labeled Viscous Hourglass Control while the second is a solid blue line labeled Stiffness Hourglass Control. The vertical axis of this graph ranges from 0.00 to 0.25 and represents Ratio of Hourglass to Internal Energies while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). The green line begins near the top of the graph at the points of 0.22 on the vertical axis and zero on the horizontal axis and runs parallel with the vertical axis straight down to the points of zero on both the vertical and horizontal axes. From there, the green line gradually rises to the points of 0.02 on the vertical axis and 140 on the horizontal axis where it rises more steeply until it runs off the graph at the points of 0.05 on the vertical axis and 200 on the horizontal axis. The blue line begins at the points of zero on both the vertical and horizontal axes and gradually rises the length of the graph until it leaves the graph at the points of 0.04 on the vertical axis and 200 on the horizontal axis.

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Figure 29. Decreasing the moisture content by 6 percent increases the post-peak force by 80 percent. Graph and Diagram.

Diagram. This diagram shows two columns standing side by side. The column on the left-hand side is broken down into three separate colors and depicts 3MC Levels. The top quarter of the column is colored a dark purple and is labeled 18.5 percent while the top middle quarter of the column is colored a dull pink and is labeled 20.0 percent. The remaining bottom quarters of the column are colored a dark red and are labeled 23.0 percent. The column on the right hand side is broken down into four colors and depicts 5 MC Levels. The top quarter of the column is colored a dark purple and is labeled 18.5 percent while the top middle quarter of the column is colored a dull pink and is labeled 20.0 percent and 21.0 percent. Separating the latter quarter and the upcoming quarter is a thin orange line labeled 22.0 percent. The remaining bottom quarters of the column are colored a light green and are labeled 23.0 percent.

Graph. This graph shows four distinct lines. The first line is solid red and is labeled 17 percent MC. The second line is solid blue and is labeled 3 MC Levels while the third line is solid green and is labeled 5 MC Levels. Finally, the fourth line is solid black and is labeled 23 percent MC (Saturated). The vertical axis of this graph ranges from 0 to 120 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 80 and represents deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid red line slopes upward to the points of 106 on the vertical axis and 74 on the horizontal axis where it peaks and then steeply drops off and leaves the graph at the points of 24 on the vertical axis and 80 on the horizontal axis. The solid blue line slopes upward to the points of 76 on the vertical axis and 56 on the horizontal axis where it steeply drops off to the pints of 4 on the vertical axis and 62 on the horizontal axis. From there the blue line spikes back up to the points of 20 on the vertical axis and 68 on the horizontal axis where it gradually slopes off the graph at the points of 24 on the vertical axis and 80 on the horizontal axis. The green line slopes upward to the points of 66 on the vertical axis and 58 on the horizontal axis where it steeply drops off to the points of 16 on the vertical axis and 64 on the horizontal axis. From there the green line sporadically runs off the graph at the points of 18 on the vertical axis and 80 on the horizontal axis. The black line slopes up to the points of 64 on the vertical axis and 60 on the horizontal axis where it steeply drops off to the points of 26 on the vertical axis and 66 on the horizontal axis. From there the black line spikes again to the points of 40 on the vertical axis and 76 on the horizontal axis where it then drops off again and runs off the graph at the points of 30 on the vertical axis and 80 on the horizontal axis.

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Figure 30. Post setup for dynamic bogie impact tests. Photo.

This photo has two parts. The first part shows a cross section of timber placed in a steel tube, which in turn is embedded in concrete. The point of impact is marked on the right hand side of the timber. Small sheets of neoprene are wedged on the sides of the timber. The second part shows the underside of the first photo. This side shows the section of timber splintered and jagged, broken. A piece of neoprene has been torn off from its initial setting.

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Figure 31. Processed data from the user’s bogie affect tests. Graphs A, B, and C.

  1. Force-deflection. This graph shows four distinct lines. The first line is solid red and is labeled DS-65 Southern Yellow Pine. The second is dotted yellow and is labeled Grade 1 Southern Yellow Pine while the third line is solid blue and is labeled Grade 1 Douglas fir. Finally, the fourth line is solid green and is labeled Grade 1 frozen S. Yellow Pine. The vertical axis of this graph ranges from –50 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 600 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes and run across the length of the graph in waves. The red line first peaks at the points of 90 on the vertical axis and 80 on the horizontal axis. It then slopes down to the points of –40 on the vertical axis and 190 on the horizontal axis where it slopes back up to the points of 30 on the vertical axis and 270 on the horizontal axis. The red line then sloes down again to the points of –15 on the vertical axis and 370 on the horizontal where it then slopes up one last time to the points of 15 on the vertical axis 470 on the horizontal axis. The red line completes its wave-like format, sloping down to its end at the points of -5 on the vertical axis and 550 on the horizontal axis. The remaining three lines follow the same pattern as the red, only in much smaller waves. The yellow line first peaks at the points of 50 on the vertical axis and 70 on the horizontal axis where it slopes down to the points of –20 on the vertical axis and190 on the horizontal axis. From there the yellow line slopes back up to the points of 15 on the vertical axis and 290 on the horizontal axis where it slopes down to the points of –5 on the vertical axis 360 on the horizontal axis. It then slopes back up gradually to the points of 5 on the vertical axis and 450 on the horizontal axis where it slopes back down to its end at the points of zero on the vertical axis and 600 on the horizontal axis. The blue line first peaks at the points of 45 on the vertical axis and 65 on the horizontal axis where it slopes down to the points of –15 on the vertical axis and 190 on the horizontal axis. From there the blue line slopes back up to the points of 15 on the vertical axis and 250 on the horizontal axis where it slopes down to the points of –5 on the vertical axis 340 on the horizontal axis. It then slopes back up gradually to the points of 5 on the vertical axis and 450 on the horizontal axis where it slopes back down to its end at the points of zero on the vertical axis and 600 on the horizontal axis. The green line first peaks at the points of 30 on the vertical axis and 65 on the horizontal axis where it slopes down to the points of –20 on the vertical axis and 190 on the horizontal axis. From there the green line slopes back up to the points of 10 on the vertical axis and 250 on the horizontal axis where it slopes down to the points of –5 on the vertical axis 340 on the horizontal axis. It then slopes back up gradually to the points of 5 on the vertical axis and 450 on the horizontal axis where it slopes back down to its end at the points of zero on the vertical axis and 600 on the horizontal axis.

  2. Velocity-time. This graph shows four distinct lines. The first line is solid red and is labeled DS-65 Southern Yellow Pine. The second is dotted yellow and is labeled Grade 1 Southern Yellow Pine while the third line is solid blue and is labeled Grade 1 Douglas fir. Finally, the fourth line is solid green and is labeled Grade 1 frozen S. Yellow Pine. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity (meters per second) while the horizontal axis of this graph ranges from 0.00 to 0.07 and represents Time (s). All four lines begin at the points of zero on both the vertical and horizontal axes and run across the length of the graph in waves. The red line first peaks at the points of 0.95 on the vertical axis and 0.015 on the horizontal axis. It then slopes down to the points of 0.65 on the vertical axis and 0.025 on the horizontal axis where it slopes back up to the points of 0.85 on the vertical axis and 0.035 on the horizontal axis. The red line then sloes down again to the points of 0.75 on the vertical axis and 0.045 on the horizontal where it then slopes up one last time to the points of 0.9 on the vertical axis 0.06 to its end. The remaining three lines follow the same pattern as the red, only in much smaller waves. The yellow line first peaks at the points of 0.45 on the vertical axis and 0.015 on the horizontal axis where it slopes down to the points of 0.35 on the vertical axis and 0.025 on the horizontal axis. From there the yellow line slopes back up to the points of 0.45 on the vertical axis and 0.035 on the horizontal axis where it slopes down to the points of 0.4 on the vertical axis 0.04 on the horizontal axis. It then slopes back up gradually to the points of 0.45 on the vertical axis and 0.05 on the horizontal axis to its end. The blue line first peaks at the points of 0.43 on the vertical axis and 0.015 on the horizontal axis where it slopes down to the points of 0.35 on the vertical axis and 0.025 on the horizontal axis. From there the blue line slopes back up to the points of 0.5 on the vertical axis and 0.035 on the horizontal axis where it slopes down to the points of 0.45 on the vertical axis and 0.04 on the horizontal axis. It then slopes back up gradually to the points of 0.5 on the vertical axis and 0.05 on the horizontal axis to its end. The green line first peaks at the points of 0.3 on the vertical axis and 0.015 on the horizontal axis where it slopes down to the points of 0.2 on the vertical axis and 0.025 on the horizontal axis. From there the green line slopes back up to the points of 0.25 on the vertical axis and 0.032 on the horizontal axis where it slopes down to the points of 0.2 on the vertical axis 0.04 on the horizontal axis. It then slopes back up gradually to the points of 0.25 on the vertical axis and 0.05 on the horizontal axis to its end.

  3. Displacement-time. This graph shows four distinct lines. The first line is solid red and is labeled DS-65 Southern Yellow Pine. The second is dotted yellow and is labeled Grade 1 Southern Yellow Pine while the third line is solid blue and is labeled Grade 1 Douglas fir. Finally, the fourth line is solid green and is labeled Grade 1 frozen S. Yellow Pine. The vertical axis of this graph ranges from 0 to 700 and represents Displacement (millimeters) while the horizontal axis of this graph ranges from 0.00 to 0.07 and represents Time (s). All four lines run diagonally across the graph in a straight-line beginning at the points of zero on both the vertical and horizontal axes. The red line finds its end at the points of 550 on the vertical axis and 0.062 on the horizontal axis. The yellow line finds its end at the points of 620 on the vertical axis and 0.062 on the horizontal axis. The green line mimics the yellow line completely. The blue line finds its end at the points of 580 on the vertical axis and 0.062 on the horizontal axis.

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Figure 32. Damage in the breakaway region of the posts, just below ground level. Photos A, B, C, and D.

  1. DS-65 pine. This photo shows two halves of a cross section of timber. The impact area is splintered intensely. So intensely in fact, that the first half of the timber is split lengthwise in two separate halves itself. The points of impact are jagged and rough, torn from each other.

  2. Grade 1 pine. This photo shows two halves of a cross section of timber. This split is somewhat clean though jagged. The two pieces would appear to still fit together in a semi-normal fashion regardless of the impact.

  3. Grade 1 frozen pine. This photo shows two halves of a cross section of timber. The impact area is completely clean. The timber is split into without splintering or any visible tearing of the grain. The break is clean and concise.

  4. Grade 1 fir. This photo shows two halves of a cross section of timber. The impact has caused minimal splintering, though the effect does exist. The splintered pieces on the left-hand piece of the timber are bent downward and are finite. The two pieces look as if they would not fit back together too easily if at all.

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Figure 33. These correlations between the LS-DYNA calculations and performance envelopes were used to adjust the parallel fracture energy for grade 1 pine to 50 times the perpendicular fracture energy. Graphs.

The first graph shows four distinct lines. The first line is solid black and is labeled LS-DYNA Calculation G subscript F equals 50 while the second line is solid gray and is labeled LS-DYNA Calculation G subscript F equals 250. Finally, the third and fourth lines are solid pink and are labeled Performance Envelopes. The vertical axis of this graph ranges from 0 to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All lines begin at the points of zero on both the vertical and horizontal axes. The solid black line slopes up to the points of 3,600 on the vertical axis and 100 on the horizontal axis where it nearly plateaus for a bit before sloping upward further until lit leaves the graph at the points of 4,800 on the vertical axis and 200 on the horizontal axis. The solid gray line slopes upward steeply and continuously until it leaves the graph at the points of 8,000 on the vertical axis and 200 on the horizontal axis. There are two separate pink lines. The first slopes up continually to the points of 5,000 on the vertical axis and 160 on the horizontal axis where it ends. The second pink line slopes up to the points of 3,800 on the vertical axis and 160 on the horizontal axis where it too finds it end.

The second graph shows three distinct lines. The first is pink dashed and is labeled Grade 1 Southern Yellow Pine Test 65 while the second is solid black and is labeled LS-DYNA Calculation G subscript F equals 50. The third and final line is solid gray and is labeled LS-DYNA Calculation G subscript F equals 250. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of zero on both the vertical and horizontal axis. The pink dashed line moves across the graph in waves. It slopes up to its first peak at the points of 0.45 on the vertical axis and 13 on the horizontal axis where it then drops back down to the points of 0.3 on the vertical axis and 24 on the horizontal axis. From there it moves back up to the points of 0.45 on the vertical axis and 34 on the horizontal axis where it moves in the slightest wave across the rest of the graph, leaving it at the points of 0.43 on the vertical axis and 60 on the horizontal axis. The solid black line gradually slopes up in sporadic spurts to the points of 0.54 on the vertical axis and 25 on the horizontal axis where it ends. The solid gray line slopes up steeply until it leaves the top of the graph at the points of 1.0 on the vertical axis and 25 on the horizontal axis.

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Figure 34. These correlations between the LS-DYNA calculations and the performance envelopes were used to adjust the parallel fracture energy for DS-65 pine to 85 times the perpendicular fracture energy. Graphs.

The first graph shows three distinct lines. The first line is solid gray and is labeled LS-DYNA Calculation G subscript F equals 85 while the second and third lines are labeled Performance Envelopes. The vertical axis of this graph ranges from 0 to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). The solid gray line slopes upward continually until it leaves the graph at the points of 7,500 on the vertical axis and 200 on the horizontal axis. The first pink line slopes upward to the points of 8,000 on the vertical axis and 160 on the horizontal axis where it ends while the second pink line slopes upward to the points of 6,000 on the vertical axis and 160 on the horizontal axis where it too ends.

The second graph shows two distinct lines. The first is pink dashed and is labeled DS-65 Southern Yellow Pine test 1129 while the second is solid gray and is labeled LS-DYNA Calculation G subscript F equals 85. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents time (milliseconds). Both lines begin at the points of zero on both the vertical and horizontal axes. The dashed pink line lakes its way across the graph in a wave-like fashion. It first peaks at the points of 0.92 on the vertical axis and 15 on the horizontal axis where it then slopes back down to the points of 0.63 on the vertical axis and 25 on the horizontal axis. From there the pink line slopes back up to the points of 0.8 on the vertical axis and 35 on the horizontal axis where it again slopes down to the points of 0.75 on the vertical axis and 45 on the horizontal axis. From here, the pink line slopes upward one last time and runs off the graph at the points of 0.9 on the vertical axis and 60 on the horizontal axis. The solid gray line slopes upward roughly to the points of 0.95 on the vertical axis and 35 on the horizontal axis where it finds its end.

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Figure 35. These correlations between the LS-DYNA calculations and energy-deflection data were used to confirm that grade 1 Douglas fir can be simulated with the same parallel fracture energy and rate-effect parameters as grade 1 southern yellow pine, but with different quality factors. Graphs.

This graph shows eight distinct lines. The first line is solid aqua and is labeled Q subscript T equals 0.47 Q subscript C equals 0.63 G subscript F equals 50 while the second line is solid blue and is labeled Q subscript T equals 0.40 Qc equals 0.70 G subscript F equals 50. The remaining six lines are all solid pink and are labeled Grade 1 Douglas Fir Data. The vertical axis of this graph ranges from 0 to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 250 and represents Deflection (millimeters). All eight lines begin at the points of zero on both the vertical and horizontal axes. The solid aqua line slopes upward continually and off the graph at the points of 5,900 on the vertical axis and 250 on the horizontal axis. The solid blue line slopes upward gradually to the points of 4,200 on the vertical axis and 120 on the horizontal axis where it plateaus. The plateau rises slightly and runs off the graph at the points of 4,900 on the vertical axis and 250 on the horizontal axis. The first pink line slopes up to the points of 6,000 on the vertical axis and 150 on the horizontal axis where it ends. The second pink line slopes up to the points of 4,000 on the vertical axis and 170 on the horizontal axis while the third and fourth pink line slope up to the points of 3,800 on the vertical axis and 150 on the horizontal axis. The latter three lines all end at these points. The fifth pink line slopes up to the points of 3,300 on the vertical axis and 160 on the horizontal axis while the final pink line slopes up to the points of 3,000 on the vertical axis and 160 on the horizontal axis. These lines also end at those points.

The second graph shows three distinct lines. The first line is solid pink and is labeled Grade 1 Douglas Fir Test 2006 while the second line is solid aqua and is labeled Q subscript T equals 0.47 Q subscript C equals 0.63 G subscript F equals 50. The third and final line is sold blue and is labeled Q subscript T equals 0.40 Qc equals 0.70 G subscript F equals 50. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of zero on both the vertical and horizontal axes. The solid pink line moves across the graph in wave-like format, peaking first at the points of 0.42 on the vertical axis and 13 on the horizontal axis. From there it slopes downward to the points of 0.35 on the vertical axis and 23 on the horizontal axis. The pink line then slopes back up to the points of 0.45 on the vertical axis and 32 on the horizontal axis. The solid aqua line slopes up to the points of 0.7 on the vertical axis and 33 on the horizontal axis where it finds it end. The solid blue line slopes upward to the points of 0.5 on the vertical axis and 33 on the horizontal axis where it also ends.

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Figure 36. These correlations between the LS-DYNA calculations and energy-deflection data were used to set the parallel fracture energy for frozen grade 1 pine to five times the perpendicular fracture energy. Graphs.

This graph shows eight distinct lines. The first line is solid black and is labeled LS-DYNA Calculation while the remaining seven lines are solid pink and are labeled Grade 1 Frozen Fir Data. The vertical axis of this graph ranges from 0 to 10,000 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). The solid black line rises very gradually to the points of 3,000 on the vertical axis and 100 on the horizontal axis where the line plateaus and runs straight off the graph. The first pink line slopes upward to the points of 5,800 on the vertical axis and 140 on the horizontal axis where it ends. The second pink line slopes upward to the points of 5,000 on the vertical axis and 140 on the horizontal axis where it ends. The third pink line slopes upward to the points of 3,400 on the vertical axis and 150 on the horizontal axis while the fourth pink line slopes upward to the points of 3,200 on the vertical axis and 160 on the horizontal axis. Both find their ends at these points. The fifth pink line slopes upward to the points of 2,400 on the vertical axis and 130 on the horizontal axis where it ends. Finally, the sixth pink line slopes upward to the points of 3,200 on the vertical axis and 140 on the horizontal axis while the seventh line slopes upward to the points of 1,200 on the vertical axis and 130 on the horizontal axis. Both find their ends at these points.

This second graph shows two distinct lines. The first line is solid pink and is labeled Grade 1 Frozen Pine test 415F. The second line is solid black and is labeled LS-DYNA Calculation. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity (meters per second) while the horizontal axis ranges from 0 to 60 and represents Time (milliseconds). The pink line runs across the length of the graph in a casual wave-like fashion, beginning at the points of zero on both the vertical and horizontal axes. The pink line first peaks at the points of 0.3 on the vertical axis and 13 on the horizontal axis before it slopes back down to the points of 0.2 on the vertical axis and 24 on the horizontal axis. It rises again casually to the points of 0.24 on the vertical axis and 33 on the horizontal axis. From there the pink line gradually runs off the graph at the points of 0.2 on the vertical axis and 60 on the horizontal axis. The black line slope upward to the points of 0.4 on the vertical axis and 21 on the horizontal axis where it ends.

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Figure 37. The simulated post breaks just below ground level, in agreement with the failure location observed in the tests. Diagrams A, B, and C.

  1. With rigid support. This diagram shows two rectangular columns, one considerable smaller and more narrow than the other and set upon the larger of the two. The narrower column is tilted to the right, showing a minute gap between the top surface of the larger column and the bottom of the smaller.

  2. Without rigid support. This diagram shows one single rectangular column with two sheets of neoprene on either side of the structure. The top half of the structure is tilted to the right, showing a large gap in the center of the column.

  3. Fringes of damage. This diagram shows one rectangular column broken down into individual squares to map the exacting damage to the structure. The structure itself is contains columns approximately forty-five squares in length, and rows consisting of eight squares across. The structure is without color to accentuate the damage areas. The top half of the structure is tilting to the right, revealing a large gap in its integrity. A small column of eight squares, three rows in, are colored a deep red below the gap insisting damage, along with a row of four squares two columns in above the gap.

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Figure 38. The user's bogie geometric model used in the developer's calculations. Diagram.

This diagram shows a computer generated rough outline of a vehicle on a planed surface. The front bumper is accentuated by a long beam, which a cylindrical structure is attached to lengthwise. This cylindrical structure is resting against a rectangular column embedded in a larger rectangular structure beneath the planed surface.

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Figure 39. The filtered bogie acceleration history sampled at 3200 Hertz is significantly different from the history sampled at 10,000 Hertz. Graphs A and B.

  1. Calculated acceleration histories. This graph shows four distinct lines. The first line is colored light blue and is labeled Unfiltered, ten thousand samples per s second. The second line is colored dark blue and is labeled Filtered, ten thousand samples per second. The third line is colored orange and is labeled Unfiltered, thirty-two hundred samples per second while the four and final line is colored red and is labeled Filtered, thirty-two hundred samples per second. The vertical axis of this graph ranges from negative .20 to 0.20 and represents Acceleration in miles per second while the horizontal axis of this graph ranges from zero to 20 and represents time in milliseconds. The first line, the light blue line oscillates heavily at the beginning between negative .20 and positive .20 on the vertical axis, with the oscillation gradually growing weaker as the line runs across the graph leaving the graph at the point of 0.00 on the vertical axis and 20 on the horizontal axis.The second line, the dark blue line begins at the point of negative 0.03 on the vertical axis and zero on the horizontal axis where it then runs across the graph in a slight wave until it leaves the graph at the point of negative 0.01 on the vertical axis and 20 on the horizontal axis. The third line, the orange line oscillates lightly at the beginning between negative .20 and positive .20 on the vertical axis, with the oscillation gradually growing weaker as the line runs across the graph leaving the graph at the point of 0.00 on the vertical axis and 20 on the horizontal axis. The fourth and final line, the red line, begins at the point negative 0.05 on the vertical axis and zero on the horizontal axis where it hen slopes down to the point of negative 0.12 on the vertical axis and 5 on the horizontal axis. From this point, the line then ascends, sloping upwards and off the graph at the point of negative 0.01 on the vertical axis and 20 on the horizontal axis.

  2. Calculated force-deflection histories. This graph shows three distinct lines. The first line is solid yellow and is labeled Grade 1 Southern Yellow Pine test 657. The second line is solid blue and is labeled Rigid bogie, ten thousands samples per second. The third and final line is solid red and is labeled Rigid Bogie, thirty-two hundred samples per second. The vertical axis of this graph ranges from negative 50 to 150 and represents Force in kilonewtons while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection in millimeters. All three lines begin at the points of zero on both the vertical and horizontal axes. The first line, the yellow line, ascends from its starting point in a slope to 50 on the vertical axis and 80 on the horizontal axis where it then slopes back down and off the graph at the points of negative 20 on the vertical axis and 180 on the horizontal axis. The second line, the blue line, ascends from its starting point to 50 on thee vertical axis and 35 on the horizontal axis where it then descends in waves until it leaves the graph at the points of zero on the vertical axis and 180 on the horizontal axis. The third and final line, the red line, ascends from its starting point to 125 on the vertical axis and 50 on the horizontal axis where it then slopes down and off the graph at the points of negative 10 on the vertical axis and 180 on the horizontal axis.

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Figure 40. Force-deflection histories calculated from bogie nodal accelerations depend significantly on the bogie type and output sampling frequency. Graph.

This graph shows five distinct lines. The first is solid yellow and is labeled Grade 1 Southern Yellow Pine Test 657. The second line is solid blue and is labeled Rigid Bogie, 10000 Samples per second while the third line is solid red and is labeled Rigid Bogie, 3200 Samples per second. The fourth line is solid aqua and is labeled Elastic Bogie, Accelerometer Node, 3200 Samples per second. Finally, the fifth and final line is solid green and is labeled elastic Bogie, Cylinder Node, 3200 Samples per second. The vertical axis of this graph ranges from –50 to 150 and represents force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All five lines begin at the points of zero on both the vertical and horizontal axes. The solid yellow line slopes upward gradually to the points of 50 on the vertical axis and 80 on the horizontal axis where it then slopes downward and off the graph at the points of –20 on the vertical axis and 200 on the horizontal axis. The solid blue line moves across the graph in minute waves. It first peaks at the points of 50 on the vertical axis and 40 on the horizontal axis and then slopes back down to the points of 40 on the vertical axis and 60 on the horizontal axis. From there the blue line slopes up ever so slightly again to the points of 45 on the vertical axis and 80 on the horizontal axis where it then slopes back down and off the graph at the points of zero on the vertical axis and 200 on the horizontal axis. The solid red line slopes up significantly to the points of 120 on the vertical axis and 40 on the horizontal axis. It then slopes down steeply and runs off the graph at the points of –10 on the vertical axis and 200 on the horizontal axis. The solid aqua line runs across the graph in pronounced waves. The first peak the aqua line reaches is at the points of 70 on the vertical axis and 40 on the horizontal axis where it then slopes down to the points of 10 on the vertical axis and 65 on the horizontal axis. From there it slopes upward to the points of 55 on the vertical axis and 90 on the horizontal axis where it slopes down steeply to the points of –25 on the vertical axis and 110 on the horizontal axis. At this point, the aqua line slopes upward to the points of 45 on the vertical axis and 135 on the horizontal axis where it slopes down one last time to the points of-15 on the vertical axis and 155 on the horizontal axis. The aqua line slopes upward on more time to the points of 50 on the vertical axis and 200 on the horizontal axis where it ends. The solid green line first peaks at the points of 50 on the vertical axis and 40 on the horizontal axis. From there it wavers down to the points of 25 on the vertical axis and 120 on the horizontal where it continues to waver until it falls off the graph at the points of zero on the vertical axis and 200 on the horizontal axis.

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Figure 41. The force-deflection histories calculated from the wood post cross-sectional forces are not significantly affected by details of the bogie model or sampling frequency. Graph.

This graph shows four distinct lines. The first line is solid yellow and is labeled Grade 1 Southern Yellow Pine test 657 while the second is solid blue and is labeled Rigid Bogie, Sampled at 3200 Hertz. The third line is solid red and is labeled rigid bogie, sampled at 10000 Hertz. Finally, the fourth and final line is solid green and is labeled Elastic Bogie, Samples at 10000 Hertz. The vertical axis of this graph ranges from 0 to 70 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The yellow line slopes upward where it peaks at the points of 50 on the vertical axis and 75 on the horizontal axis and then slopes downward steeply and leaves the graph at the points of zero on the vertical axis and 150 on the horizontal axis. The blue line slopes up to the points of 40 on the vertical axis and 45 on the horizontal axis where it then curves downward and off the graph at the points of 5 on the vertical axis and 200 on the horizontal axis. The bred line slopes up to the points of 40 on the vertical axis and 50 on the horizontal axis where it then curves downward and off the graph at the points of 5 on the vertical axis and 200 on the horizontal axis. The green line slopes up to the points of 43 on the vertical axis and 50 on the horizontal axis where it then curves downward and off the graph at the points of 15 on the vertical axis and 200 on the horizontal axis.

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Figure 42. The internal energy calculated to break the wood post is less than the kinetic energy reduction of the bogie. Graph.

This graph shows four distinct lines. The first line is solid black and is labeled Bogie Kinetic Energy Reduction while the second is black dotted and is labeled Post Cross-Sectional Force. The remaining two lines are both solid pink and are labeled Performance Envelopes. The vertical axis of this graph ranges from o to 10,000 and represents energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid black line runs in a continuous slope across the length of the graph where it leaves the graph at the points of 4,800 on the vertical axis and 200 on the horizontal axis. The black dotted line slopes upward to the points of 3,200 on the vertical axis and 195 on the horizontal axis where it ends. The first pink line slopes upward to the points of 5,000 on the vertical axis and 165 on the horizontal axis where it finds its end while the second pink line slopes up to the points of 3,800 on the vertical axis and 165 on the horizontal axis where it ends.

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Figure 43. These deformed configurations at 180 millimeters of deflection indicate that adjustments in the quality factors affect the deflection at which the grade 1 pine post breaks in two. Diagrams A and B.

  1. Q subscript T equals 0.47 and Q subscript C equals 0.63. This diagram shows one rectangular column broken down into individual squares to map the exacting damage to the structure. The structure itself is contains columns approximately 45 squares in length, and rows consisting of eight squares across. The structure is without color to accentuate the damage areas. The top half of the structure is tilting to the right, revealing a large gap in its integrity. A small column of eight squares, three rows in, are colored a deep red below the gap insisting damage, along with a row of four squares two columns in above the gap.

  2. Q subscript T equals 0.40 and Q subscript C equals 0.70. This diagram shows one single rectangular column with two sheets of neoprene on either side of the structure. The top three-quarters of the structure is tilted to the right, showing a large gap in the column, between the sheets of neoprene.

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Figure 44. Although the grade 1 pine post breaks earlier in time with Q subscript T equals 0.40 and Q subscript C equals 0.70, the calculated energy and velocity histories are similar. Graphs.

The first graph shows four distinct lines. The first line is solid black and is labeled Q subscript T equals 0.47 and Q subscript C equals 0.63 while the second is solid green and is labeled Q subscript T equals 0.40 and Q subscript C equals 0.70. The remaining two lines are both solid pink and are labeled Performance Envelopes. The vertical axis of this graph ranges from o to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid black line runs in a continuous slope across the length of the graph where it leaves the graph at the points of 4,600 on the vertical axis and 200 on the horizontal axis. The solid green line slopes upward to the points of 4,400 on the vertical axis and 200 on the horizontal axis where it ends. The first pink line slopes upward to the points of 5,000 on the vertical axis and 165 on the horizontal axis where it finds its end while the second pink line slopes up to the points of 3,800 on the vertical axis and 165 on the horizontal axis where it ends.

This second graph shows three distinct lines. The first line is pink dashed and is labeled Grade 1 Southern Yellow Pine test 657. The second line is solid black and is labeled Q subscript T equals 0.47 and Q subscript C equals 0.63 while the third and final line is solid green and is labeled Q subscript T equals 0.40 and Q subscript C equals 0.70. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of zero on both the vertical and horizontal axes. The pink dashed line first peaks at the points of 0.45 on the vertical axis and 13 on the horizontal axis where it then slopes back down to the points of 0.32 on the vertical axis and 24 on the horizontal axis. From there the pink dashed line rises again to the points of 0.45 on the vertical axis and33 on the horizontal axis where it wavers across the remainder of the graph and exits at the points of 0.48 on the vertical axis and 60 on the horizontal axis. The solid black line slopes up steeply to the points of 0.54 on the vertical axis and 24 on the horizontal axis where it ends. The solid green line slopes up steeply where it comes to its end at the points of 0.6 on the vertical axis and 35 on the horizontal axis.

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Figure 45. The default number of plasticity algorithm iterations is set to one because these static load-deflection curves are insensitive to the number of iterations. Graph.

This graph shows two distinct lines. The first is dotted green and is labeled 5 Iterations while the second is solid pink and is labeled 1 Iteration. The vertical axis of this graph ranges from 0 to 60 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). Both lines begin at the points of zero on both the vertical and horizontal axes. The dotted green line rises steeply to where it peaks at the points of 49 on the vertical axis and 50 on the horizontal axis. From there the line slopes downward sporadically to the points of 16 on the vertical axis and 80 on the horizontal axis where it spikes in the slightest to the points of 20 on the vertical axis and 90 on the horizontal axis. The green line then descends irregularly until it exits the graph at the points of 7 on the vertical axis and 200 on the horizontal axis. The pink line runs exact same path at the dotted green line until it reaches its descending points of 20 on the vertical axis and 90 on the horizontal axis. From there the pink line breaks from the green line, descending irregularly and leaving the graph at the points of 5 on the vertical axis and 200 on the horizontal axis.

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Figure 46. Erosion affects the fully integrated element curves, but not the under-integrated element curves, indicating that the fully integrated elements erode while still carrying load. Graph.

This graph shows two distinct lines. The first line is solid blue and is labeled With Erosion while the second line is solid pink and is labeled Without Erosion. The vertical axis of this graph ranges from 0 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). Both lines begin at the points of zero on both the vertical and horizontal axes. Both lines slope upward steeply to the points of 74 on the vertical axis and 70 on the horizontal axis where they drop straight off to the points of 38 on the vertical axis and 72 on the horizontal axis. From there the two lines split. The blue line spikes back up slightly to the points of 40 on the vertical axis and 80 on the horizontal axis where the line then plateaus to the points of 40 on the vertical axis and 150 on the horizontal axis. The blue line then drops off erratically and falls off the graph at the points of zero on the vertical axis and 175 on the horizontal axis. The yellow line spikes up also to the points of 40 on the vertical axis and 80 on the horizontal axis and then plateaus as a slight downgrade to the points of 38 on the horizontal axis and 150 on the vertical axis. From there it continues to slope downward and off the graph at the points of 28 on the vertical axis and 200 on the horizontal axis.

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Figure 47. Deformed configurations and fringes of damage calculated with fully integrated elements (eight points) are similar to those calculated with under-integrated elements (one point). Diagrams A and B.

  1. With eight-point integration. This diagram shows a rectangular column. The column is void of color to accentuate the areas of damage. The column is sheeted on either side by what would be neoprene, approximately fifteen rows up from the bottom of the structure. The top half of the structure is tilted to the right, a five squares of a row missing where the neoprene line ends. A column of ten squares, three columns in is colored a dark red, the eleventh square colored a dark blue. These columns exist below the gap formed by the tilt of the upper half. In the row of squares above the gap, two of the eight squares are colored a dark blue.

  2. With one-point integration. This diagram shows a rectangular column. The column is void of color to accentuate the areas of damage. The column is sheeted on either side by what would be neoprene, approximately fifteen rows up from the bottom of the structure. The top half of the structure is tilted to the right, a five squares of a row missing where the neoprene line ends. A column of eight squares, three columns in is colored a dark red, the ninth square colored a pale green. The column next to the latter has its first square colored a dark red and the next colored a pale green. These columns exist below the gap formed by the tilt of the upper half. In the row of squares above the gap, four of the eight squares are colored a dark red, where the next row up has three of the eight colored a dark blue.

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Figure 48. Energy-deflection and bogie velocity-reduction histories are not strongly influenced by the type of element formulation (eight points or one point) modeled in the breakaway regime. Graphs.

The first graph shows four distinct lines. The first line is solid green and is labeled 8 Point Integration while the second is solid black and is labeled 1 Point Integration. The remaining two lines are both solid pink and are labeled Performance Envelopes. The vertical axis of this graph ranges from 0 to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid green line runs in a continuous slope across the length of the graph where it leaves the graph at the points of 4,600 on the vertical axis and 200 on the horizontal axis. The solid black line slopes upward to the points of 4,600on the vertical axis and 200 on the horizontal axis where it ends. The first pink line slopes upward to the points of 5,000 on the vertical axis and 165 on the horizontal axis where it finds its end while the second pink line slopes up to the points of 3,800 on the vertical axis and 165 on the horizontal axis where it ends.

This second graph shows three distinct lines. The first line is pink dashed and is labeled Grade 1 Southern Yellow Pine test 657. The second line is solid black and is labeled 1 Point Integration while the third and final line is solid green and is labeled 8 Point Integration. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of zero on both the vertical and horizontal axes. The pink dashed line first peaks at the points of 0.45 on the vertical axis and 13 on the horizontal axis where it then slopes back down to the points of 0.32 on the vertical axis and 24 on the horizontal axis. From there the pink dashed line rises again to the points of 0.45 on the vertical axis and 33 on the horizontal axis where it wavers across the remainder of the graph and exits at the points of 0.48 on the vertical axis and 60 on the horizontal axis. The solid black line slopes up steeply to the points of 0.54 on the vertical axis and 24 on the horizontal axis where it ends. The solid green line slopes up steeply where it comes to its end at the points of 0.6 on the vertical axis and 35 on the horizontal axis.

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Figure 49. The breakaway region calculated with perpendicular erosion in these static bending simulations looks more realistic than that calculated without perpendicular erosion, but perpendicular erosion is not recommended for practical use. Diagrams A, B, and C.

  1. Without perpendicular erosion. This diagram shows a rectangular column broken into columns and rows of individual squares. The top three quarters of this structure are colored a dull pink with the exception of a small band near the top, which is colored a dark purple and shows an eye hook emerging from the right hand side. The last quarter of this structure is colored a dark red. A gap exists in this red section. The top three quarters of the structure is tilted to the right, creating said gap, where five squares of one particular row is missing from the structure.

  2. With perpendicular erosion. This diagram shows a rectangular column broken into columns and rows of individual squares. The top three quarters of this structure are colored a dull pink with the exception of a small band near the top, which is colored a dark purple and shows an eye hook emerging from the right hand side. The last quarter of this structure is colored a dark red. A gap exists in this red section. The top three quarters of the structure is tilted to the right, creating said gap, where five squares of one particular row is missing from the structure. There are also two squares missing, one on top of the other from the fourth column adjoined with the missing row of five.

  3. Fringes of damage. This diagram shows a rectangular column. The column is void of color to enhance the actual points of damage. The top three-quarters of the structure is tilting to the right, creating a gap of five missing squares in one row near the last quarter of the structure. In that missing row, the next square, which is present is colored a dark red. The second square in the next row down is colored a light blue. Three squares in the third column are colored a dark blue, just below the gap and three squares in the next column are colored a dark red.

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Figure 50. Load-deflection curves calculated with perpendicular erosion are slightly more brittle than those calculated without perpendicular erosion. Graph.

This graph shows two distinct lines. The first is dotted green and is labeled With Perpendicular Erosion while the second is solid pink and is labeled Without Perpendicular Erosion. The vertical axis of this graph ranges from 0 to 60 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). Both lines begin at the points of zero on both the vertical and horizontal axes. The dotted green line rises steeply to where it peaks at the points of 49 on the vertical axis and 50 on the horizontal axis. From there the red line slopes downward sporadically to the points of 16 on the vertical axis and 80 on the horizontal axis where it spikes in the slightest to the points of 20 on the vertical axis and 90 on the horizontal axis. The green line slopes down to the points of 8 on the vertical axis and 85 on the horizontal axis. From there the green line spikes up to the points of 14 on the vertical axis and 90 on the horizontal axis where it plateaus to the points of 14 on the vertical axis and 140 on the horizontal axis. The green line then drops off and runs off the graph at the points of 5 on the vertical axis and 200 on the horizontal axis. The pink line spike up slightly and then drops back down to the points of 14 on the vertical axis and 100 on the horizontal axis where it too plateaus and mimics the path of the green line off the graph.

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Figure 51. The breakaway region calculated with perpendicular erosion in this bogie impact simulation looks more realistic than that calculated without perpendicular erosion. Diagrams A and B.

  1. With perpendicular erosion. This first diagram shows a rectangular column. The column is sheeted on either side by what would be neoprene, approximately fifteen rows up from the bottom of the structure. The structure is broken down into rows and columns of small squares. The top half of the structure is colored a dull aqua with the exception of a small strip, seven rows wide, which is, colored a dull blue. A dark blue section exists near the bottom of the structure, six rows of it resting above the neoprene barrier and six rows resting below. At the mouth of the neoprene barrier, a good chunk of squares is missing. Nine squares total are missing from three columns, two columns in while the first five squares are missing in the row that rests on the neoprene line.

  2. Damage fringes without perpendicular erosion. This diagram shows a rectangular column. The column is void of color to accentuate the areas of damage. The column is sheeted on either side by what would be neoprene, approximately fifteen rows up from the bottom of the structure. The top half of the structure is tilted to the right, a five squares of a row missing where the neoprene line ends. A column of eight squares, three columns in is colored a dark red, the ninth square colored a pale green. The column next to the latter has its first square colored a dark red and the next colored a pale green. These columns exist below the gap formed by the tilt of the upper half. In the row of squares above the gap, four of the eight squares is colored a dark red, where the next row up has three of the eight colored a dark blue.

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Figure 52. Dynamic load-deflection and bogie velocity-reduction curves calculated with perpendicular erosion are nearly identical to those calculated without perpendicular erosion. Graphs.

The first graph shows four distinct lines. The first line is solid green and is labeled With Perpendicular Erosion while the second is solid black and is labeled Without Perpendicular. The remaining two lines are both solid pink and are labeled Performance Envelopes. The vertical axis of this graph ranges from o to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid green line runs in a continuous slope across the length of the graph where it leaves the graph at the points of 4,600 on the vertical axis and 200 on the horizontal axis. The solid black line slopes upward to the points of 4,600on the vertical axis and 200 on the horizontal axis where it ends. The first pink line slopes upward to the points of 5,000 on the vertical axis and 165 on the horizontal axis where it finds its end while the second pink line slopes up to the points of 3,800 on the vertical axis and 165 on the horizontal axis where it ends.

This second graph shows three distinct lines. The first line is pink dashed and is labeled Grade 1 Southern Yellow Pine test 657. The second line is solid black and is labeled Without Perpendicular Erosion while the third and final line is solid green and is labeled With Perpendicular Erosion. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of zero on both the vertical and horizontal axes. The pink dashed line first peaks at the points of 0.45 on the vertical axis and 13 on the horizontal axis where it then slopes back down to the points of 0.32 on the vertical axis and 24 on the horizontal axis. From there the pink dashed line rises again to the points of 0.45 on the vertical axis and33 on the horizontal axis where it wavers across the remainder of the graph and exits at the points of 0.48 on the vertical axis and 60 on the horizontal axis. The solid black line slopes up steeply to the points of 0.54 on the vertical axis and 24 on the horizontal axis where it ends. The solid green line slopes up steeply where it comes to its end at the points of 0.54 on the vertical axis and 24 on the horizontal axis.

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Figure 53. Use of perpendicular erosion causes erosion to be calculated in the impact regime in this preliminary bogie impact calculation. Diagram.

The first graph shows four distinct lines. The first line is solid green and is labeled With Perpendicular Erosion while the second is solid black and is labeled Without Perpendicular. The remaining two lines are both solid pink and are labeled Performance Envelopes. The vertical axis of this graph ranges from o to 10,000 and represents Energy (kilonewton-millimeters) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All four lines begin at the points of zero on both the vertical and horizontal axes. The solid green line runs in a continuous slope across the length of the graph where it leaves the graph at the points of 4,600 on the vertical axis and 200 on the horizontal axis. The solid black line slopes upward to the points of 4,600on the vertical axis and 200 on the horizontal axis where it ends. The first pink line slopes upward to the points of 5,000 on the vertical axis and 165 on the horizontal axis where it finds its end while the second pink line slopes up to the points of 3,800 on the vertical axis and 165 on the horizontal axis where it ends.

This second graph shows three distinct lines. The first line is pink dashed and is labeled Grade 1 Southern Yellow Pine test 657. The second line is solid black and is labeled Without Perpendicular Erosion while the third and final line is solid green and is labeled With Perpendicular Erosion. The vertical axis of this graph ranges from 0.0 to 1.0 and represents Velocity Reduction (meters per second) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of zero on both the vertical and horizontal axes. The pink dashed line first peaks at the points of 0.45 on the vertical axis and 13 on the horizontal axis where it then slopes back down to the points of 0.32 on the vertical axis and 24 on the horizontal axis. From there the pink dashed line rises again to the points of 0.45 on the vertical axis and33 on the horizontal axis where it wavers across the remainder of the graph and exits at the points of 0.48 on the vertical axis and 60 on the horizontal axis. The solid black line slopes up steeply to the points of 0.54 on the vertical axis and 24 on the horizontal axis where it ends. The solid green line slopes up steeply where it comes to its end at the points of 0.54 on the vertical axis and 24 on the horizontal axis.

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Figure 54. These single-element simulations demonstrate post-peak hardening in compression with positive values of G subscript hard. Graph.

This graph shows three distinct lines. The first line is solid green and is labeled G subscript hard plus 1.00 while the second line is solid blue and is labeled G subscript hard equals 0.05. The third and final line is solid red and is labeled G subscript hard equals 0.00. The vertical axis of this graph ranges from 0 to 50 and represents Stress (megapascals) while the horizontal axis of this graph ranges from 0.0 to 2.0 and represents Strain (percent). All three lines begin at the points of zero on both the vertical and horizontal axes. The green line runs diagonally across the graph in a steep line to the points of 50 on the vertical axis and 1.0 on the horizontal axis where it leaves the graph. The blue and red lines run one on top of the other as they slope upward to the points of 20 on the vertical axis and 0.8 on the horizontal axis where the two lines split. The blue line continues a gradually climb until it leaves the graph at the points of 23 on the vertical axis and 2.0 on the horizontal axis. The red line plateaus and runs straight off the graph at the points of 20 on the vertical axis and 2.0 on the horzontal axis.

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Figure 55. Inclusion of post-peak hardening, both parallel and perpendicular to the grain, prevented this calculation from aborting at large deflection. Diagram

This diagram shows a long rectangular column encased by two shorter and wider rectangular columns on either side of the first. The two wider structures are colored a dark green and are tied together by four cross bars, which reach over the longer structure which itself is colored a dull pink. The two wider structures run up the sides of the longer structure and stop at about the half way points. At this point, the pink structure is titled severely to the right, the structure torn and jagged at the point of impact.

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Figure 56. Performance envelopes from 1995 NDOR testing. Graphs.

  1. Grade DS-65: This graph shows four distinct lines. The first two are solid black and are labeled Static while the last two are dotted black and are labeled Dynamic. This vertical axis of this first graph ranges from 0 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection (millimeters). The vertical axis of this graph ranges from zero to 100 and represents Force (kilonewtons) while the horizontal axis ranges from zero to 180 and represents Deflection in millimeters. All four lines begin at the points of zero on both axes. The first black line rises in a wide arc from the point of zero and ascends to the point of 80 on the vertical axis and 60 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 30 on the vertical axis and 180 on the horizontal axis. The second black line rises in a wide arc from the point of zero and ascends to the point of 68 on the vertical axis and 60 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 20 on the vertical axis and 180 on the horizontal axis. The first black dotted line rises from its starting point in one large arc, peaking at the point of 92 on the vertical axis and 80 on the horizontal axis before descending to the point of zero on the vertical axis and 160 on the horizontal axis where it comes to an end. The second black dotted line rises from its starting point in one large arc, peaking at the point of 70 on the vertical axis and 80 on the horizontal axis before descending to the point of zero on the vertical axis and 145 on the horizontal axis where it comes to an end.

  2. Grade 1: This graph shows four distinct lines. The first two are solid black and are labeled Static while the last two are dotted black and are labeled Dynamic. This vertical axis of this first graph ranges from 0 to 100 and represents Force (kilonewtons) while the horizontal axis of this graph ranges from 0 to 180 and represents Deflection (millimeters). The vertical axis of this graph ranges from zero to 100 and represents Force (kilonewtons) while the horizontal axis ranges from zero to 180 and represents Deflection in millimeters. All four lines begin at the points of zero on both axes. The first black line rises in a small arc from the point of zero and ascends to the point of 56 on the vertical axis and 44 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 10 on the vertical axis and 180 on the horizontal axis. The second black line rises in a wide arc from the point of zero and ascends to the point of 48 on the vertical axis and 40 on the horizontal axis where it then begins to descend unevenly and gradually until it leaves the graph at the point of 6 on the vertical axis and 180 on the horizontal axis. The first black dotted line rises from its starting point in one wide arc, peaking at the point of 54 on the vertical axis and 90 on the horizontal axis before descending to the point of zero on the vertical axis and 162 on the horizontal axis where it comes to an end. The second black dotted line rises from its starting point in one large arc, peaking at the point of 44 on the vertical axis and 80 on the horizontal axis before descending to the point of zero on the vertical axis and 140 on the horizontal axis where it comes to an end.

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Figure 57. Static post setup. Photo.

This photo shows a cross section of timber lying on its side on a concrete surface. The piece of timber is fastened inside a steel frame, with four cross bars bolted across the top to hold the timber in place, while the apparatus itself is bolted directly to the concrete floor. A pulley system is rigged across the floor a ways, itself bolted into a concrete wall. From the wall emerges a long hydrolytic looking apparatus. To this apparatus is fastened a long steel cable, which itself is fasted to a large pulley, which in turn is fasted to an even larger hook. This hook is threaded through the eye of a large bolt, which has been drilled into the top half of the piece of timber and fasted through the other side. It would appear the hydraulic pulls the steel cable through the pulley, in turn pulling on the eye threaded through the timber until the timber snaps.

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Figure 58. Dynamic post setup. Photos.

The first photo shows a cross section of timber embedded into a concrete surface, standing straight up. A video camera is set up on a tripod and is aimed at the post. A vehicle is positioned a short distance from the post. This vehicle has a large cylindrical structure attached to the front of it to serve as a bumper, which is used at the points of impact.

The second photo shows a close up of the cross section of timber embedded in the concrete. Sheets of neoprene a draped out of the hole in which the timber is inserted.

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Figure 59. Typical static post test results. Photos.

DS-65. This photo shows a cross section piece of timber fastened inside a steel frame, lying lengthwise from top to bottom on a concrete surface. The steel frame itself is fastened to the concrete surface, and four cross bar are bolted across the top of the piece of timber holding it in its place. There exists an eye-hook run through the top of the timber with a pulley cable and hook attached to this eye-hook. The timber has split along the length of its grain, down its center and has cracked along its left-hand side as the right hand side of the timber was being forced against the steel frame.

DS-65 closeup. This photo shows a closeup of a cross section of timber fastened in a steel frame, which in turn is fastened to a concrete surface. Two of the four cross bars are visible in this closeup. The timber has snapped, the timber cracking beginning between the first and second cross bar moving in a diagonal fashion three quarters of the way through the width of the beam.

Grade 1D. This photo shows a cross section piece of timber fastened inside a steel frame, lying lengthwise at a slight angle from top to bottom on a concrete surface. The steel frame itself is fastened to the concrete surface, and four cross bar are bolted across the top of the piece of timber holding it in its place. There exists an eye-hook run through the top of the timber with a pulley cable and hook attached to this eye-hook. The timber has split along its left-hand side severely as the right hand side of the timber was forced against the steel frame.

Grade 1D closeup. This photo shows a closeup of a cross section of timber fastened in a steel frame, which in turn is fastened to a concrete surface. Only one of the four cross bars are visible in this closeup. The fracture begins and remains nearly parallel with the visible cross bar, splitting the timber straight across the width of the beam.

Grade 1. This photo shows a cross section piece of timber fastened inside a steel frame, lying lengthwise from top to bottom on a concrete surface. The steel frame itself is fastened to the concrete surface, and four cross bar are bolted across the top of the piece of timber holding it in its place. There exists an eye-hook run through the top of the timber with a pulley cable and hook attached to this eye-hook. The timber has split along the length of its grain, down its center and has cracked along its left-hand side as the right hand side of the timber was being forced against the steel frame.

Grade 1 closeup. This photo shows a closeup of a cross section of timber fastened in a steel frame, which in turn is fastened to a concrete surface. Only one of the four cross bars are visible in this closeup. The timber has snapped, the timber cracking beginning between the first and second cross bar moving in a diagonal fashion three quarters of the way through the width of the beam.

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Figure 60. Typical dynamic post test results. Photos.

DS-65 closeup. This photo shows a cross section of timber where it has broken inside the concrete that it was embedded in. Sheets of neoprene can be seen on either side of the timber. The break is clean, without jagged edges.

DS-65. This photo shows a cross section of timber that has been snapped in two pieces. The break appears clean. Though the edges of the break are jagged, there are no splintered ends.

Grade 1D closeup. This photo shows a cross section of timber where it has broken inside the concrete that it was embedded in. Sheets of neoprene can be seen on either side of the timber. The break is uneven and jagged. The wood has splintered in several places.

Grade 1D. This photo shows a cross section of timber that has been snapped in two pieces. The break is somewhat clean, though jagged and splintered. The jagged pieces are elongated and smooth.

Grade 1 closeup. This photo shows a cross section of timber where it has broken inside the concrete that it was embedded in. Sheets of neoprene can be seen on either side of the timber. The break is uneven and jagged. The wood has splintered in several places.

Grade 1. This photo shows a cross section of timber that has been snapped in two pieces. The break is rarely clean, appearing jagged and splintered. The jagged pieces are small and compact.

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Figure 61. Other dynamic post test results. Photos.

Clean break. This photo shows a cross section of timber that has been snapped in two pieces. The break appears clean, the edges where the wood is splintered is smooth and compact, giving the impression that the two pieces could be reunited quite easily.

Atypical behavior. This photo shows a cross section of timber. Instead of a clean break, the wood has fractured along the grain lengthwise in virtually all spots along the piece of timber. The entire beam is splintered and frayed, broken in many pieces, as if exploded rather than snapped.

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Figure 62. Impact sequence of post simulation. Diagrams.

Developer’s Results

Time 0. This first diagram shows a rectangular column embedded between to separate rectangular columns. These two columns run up the side of the main structure only a quarter of the way. The two columns on either side of the main structure are colored white. The majority of the main structure is colored a dull pink, with the exception of a small fragment near to the top, which is colored a light blue and a section near the bottom, which is colored a light green. This light green section is half in/half out of the white columns. On the left-hand side of the blue section of the main structure there rests a light blue sphere attached to a darkened colored arm of a sort.

Time 9.9961. This first diagram shows a rectangular column embedded between to separate rectangular columns. These two columns run up the side of the main structure only a quarter of the way. The two columns on either side of the main structure are colored white. The majority of the main structure is colored a dull pink, with the exception of a small fragment near to the top, which is colored a light blue and a section near the bottom, which is colored a light green. This light green section is half in/half out of the white columns. On the left-hand side of the blue section of the main structure there rests a light blue sphere attached to a darkened colored arm of a sort. This arm is extended further in this diagram, forcing the top three-quarters of the main structure to lean to the right. At the point where the green section near the bottom of the main structure enters the white columns, a gap has formed due to the tilt. This gap runs through only half the width of the main structure.

Time 29.999. This first diagram shows a rectangular column embedded between to separate rectangular columns. These two columns run up the side of the main structure only a quarter of the way. The two columns on either side of the main structure are colored white. The majority of the main structure is colored a dull pink, with the exception of a small fragment near to the top, which is colored a light blue and a section near the bottom, which is colored a light green. This light green section is half in/half out of the white columns. On the left-hand side of the blue section of the main structure there rests a light blue sphere attached to a darkened colored arm of a sort. This arm is extended further in this diagram, forcing the top three-quarters of the main structure to lean to the right. At the point where the green section near the bottom of the main structure enters the white columns, a wide gap has formed due to the tilt. This gap runs through three-quarters the width of the main structure.

User’s Results

Time 0. This first diagram shows a rectangular column embedded between to separate rectangular columns. These two columns run up the side of the main structure only a quarter of the way. The two columns on either side of the main structure are colored white. The majority of the main structure is colored a dull pink, with the exception of a small fragment near to the top, which is colored a light blue and a section near the bottom, which is colored a light green. This light green section is half in/half out of the white columns. On the left-hand side of the blue section of the main structure there rests a light blue sphere attached to a darkened colored arm of a sort.

Time 9.9961. This first diagram shows a rectangular column embedded between to separate rectangular columns. These two columns run up the side of the main structure only a quarter of the way. The two columns on either side of the main structure are colored white. The majority of the main structure is colored a dull pink, with the exception of a small fragment near to the top, which is colored a light blue and a section near the bottom, which is colored a light green. This light green section is half in/half out of the white columns. On the left-hand side of the blue section of the main structure there rests a light blue sphere attached to a darkened colored arm of a sort. This arm is extended further in this diagram, forcing the top three-quarters of the main structure to lean to the right. At the point where the green section near the bottom of the main structure enters the white columns, a gap has formed due to the tilt. This gap runs through only half the width of the main structure.

Time 29.999. This first diagram shows a rectangular column embedded between to separate rectangular columns. These two columns run up the side of the main structure only a quarter of the way. The two columns on either side of the main structure are colored white. The majority of the main structure is colored a dull pink, with the exception of a small fragment near to the top, which is colored a light blue and a section near the bottom, which is colored a light green. This light green section is half in/half out of the white columns. On the left-hand side of the blue section of the main structure there rests a light blue sphere attached to a darkened colored arm of a sort. This arm is extended further in this diagram, forcing the top three-quarters of the main structure to lean to the right. At the point where the green section near the bottom of the main structure enters the white columns, a wide gap has formed due to the tilt. This gap runs through three-quarters the width of the main structure.

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Figure 63. Damage – stored as effective plastic strain in d3plot files. Diagrams.

The two diagrams are accompanied by a legend to the right hand side of the figure. The legend shows indicated fringe levels, in a variety of colors. The scale begins in dark blue, being the lowest fringe level, scales up through green, then yellow and into red, representing the highest fringe level.

Developer’s Results.

This figure shows a computer-generated illustration of a post. The top half of the post leans to the right at a slight degree with a gap forming near the mid-point of the structure. The majority of the post is colored a dark blue. The small section of red is visible just under the gap and on the top of the gap, as is there another section of the same color near the top of the top half of the post near the impact area.

User’s results.

This figure shows a computer-generated illustration of a post. The top half of the post leans to the right at a slight degree with a gap forming near the mid-point of the structure. The majority of the post is colored a dark blue. The small section of red is visible just under the gap and on the top of the gap, as is there another section of the same color near the top of the top half of the post near the impact area.

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Figure 64. Contact forces. Graph.

This graph shows two distinct lines. The first line is colored red and is labeled A Aptek while the second line is colored blue and is labeled B UNI. The vertical axis of this graph ranges from zero to 120 and represents X-Force in kilonewtons while the horizontal axis of this graph ranges from zero to 30 and represents Time in milliseconds. The first line, the red line, appears to begin at the point of 60 on the vertical axis and 5 on the horizontal axis. From this point the line ascend only slightly before diving to the point of zero on the vertical axis and 10 on the horizontal axis. The red line then rises again from the zero on the vertical axis and 12 on the horizontal axis where it then runs across the remainder of the graph in a wave before leaving the graph at the points of 10 on the vertical axis and 30 on the horizontal axis. The second line, the blue line, begins at the points of zero on both the vertical and horizontal axes before spiking to 116 on the vertical axis and 2 on the horizontal axis an then dropping again to zero on the vertical and 4 on the horizontal axis. The blue then spikes again to 64 on the vertical and 6 on the horizontal axis before descending to zero on the vertical and 12 on the horizontal axis. From this point the blue line rises once again before running across the graph in a nearly straight line, leaving the graph at 2 on the vertical and 30 on the horizontal axis.

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Figure 65. Cross section at ground level. Graph.

This graph shows two distinct lines. The first line is colored red and is labeled A2 Aptek while the second line is colored blue and is labeled B2 UNI. The vertical axis of this graph ranges from negative 20 to 80 and represents X-Force in kilonewtons while the horizontal axis of this graph ranges from zero to 30 and represents Time in milliseconds. The first line, the red line, appears to be gin at the points of 20 on the vertical axis and 5 on the horizontal axis. From this point the line descends slightly and oscillates across the graph gradually until it leaves the graph at the point of 2 on the vertical axis and 30 on the horizontal axis. The second line, the blue line begins at the point of zero on both axes before spiking to the point of 78 on the vertical axis and 3 on the horizontal axis. From this point he line then descends to the point of 20 on the vertical axis and 5 on the horizontal axis. He blue line then oscillates across the reminder of the graph until it leaves the graph at the point of 2 on the vertical axis and 30 on the horizontal axis.

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Figure 66. Energy of post parts. Graph.

This graph shows six distinct lines. The first line is colored red and is labeled A 8000 Aptek. The second, light green is labeled B 8001 Aptek. The third, dark blue is labeled C 8002 Aptek. The fourth, dark green is labeled D 8000 UNI. The fifth, pink is labeled E 8001 UNI. Finally, the sixth and final line, black is labeled F 8002 UNI. The vertical axis of this graph ranges from zero to2 and represents Internal energy (E plus 3) while the horizontal axis of this graph ranges from zero to 30 and represents Time. All six lines begin at the points of zero on both axes.   Lines B and E follow suit, ascending from their starting point to 0.5 on the vertical axis and 6 on the horizontal axis, where they both run across the graph in a near straight line and leave the graph at the points of 0.52 on the vertical and 30 on the horizontal axis. Lines A and D follow suit, ascending from their starting point to 0.25 on the vertical axis and 5 on the horizontal axis, where they both run across the graph in a near straight line and leave the graph at the points of 0.25 on the vertical and 30 on the horizontal axis. Finally, both lines C and F follow suit and rise from their starting point to 1.5 on the vertical axis and 15 on the horizontal axis, where the two lines split, line C rising higher than line F. Line C rises off the graph at the points of 1.75 on the vertical axis and 30 on the horizontal axis while line F rises off the graph at the point of 1.55 on the vertical axis and 30 on the horizontal axis.

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Figure 67. Bogie velocity. Graph.

This graph shows two distinct lines. The first is solid red and is labeled A 22 Aptek while the second is solid blue and is labeled B 22 UNI. The vertical axis of this graph ranges from 9.56 to 9.66 and represents X-velocity (millimeters/ms) while the horizontal axis of this graph ranges from 0 to 30 and represents time (milliseconds). Both lines run one on top of the other through the length of the graph, beginning at the points of 9.645 on the vertical axis and zero on the horizontal axis. The two lines then run downward and off the graph at the points of 9.565 on the vertical axis and 30 on the horizontal axis.

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Figure 68. Contact penetration caused locking of parts. Diagram.

This figure shows a close up section of a computer-generated image of a wood beam embedded into a frame. At the point where the post is embedded into the frame, the wood has begun to split, causing a wide gap to form, as the top half of the post leans to the left hand side of the diagram.

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Figure 69. Contact penetration caused locking of parts. Diagram.

This figure shows two separate sets of diagrams, each with three separate images.

The first set of diagrams is labeled Fast Bogie – Aptek Results. The first image in this set shows a diagram of the post used in the dynamic test simulation. It shows the full length of the post, the lower half colored a light green, the next section a light blue and the remaining top quarter s light red. No damage has of yet occurred in this first model. Near the top quarter of this model is a cylindrical device that has just begun to come in contact with the post itself.

The second image shows the same post, the cylindrical device having already impacted the structure, forcing the top half of the post to lean to the right hand side of the diagram. A small gap has begun to form a short way down into the green colored section of the post.

The third image in this set shows the same post, the cylindrical device having impacted the structure more fierce, forcing the post to lean considerably to the right hand side of the diagram.

The top half of the post now leans at a rough forty-five degree angle from its original position, making a considerably larger gap in the initial fracture of the post. The fracture itself appears level, the break clean.

The second set of diagrams is labeled Fast Bogie – UNL results. The first image in this set shows a diagram of the post used in the dynamic test simulation. The time recorded on this first diagram reads Time = zero. It shows the full length of the post, the lower half colored a light green, the next section a light blue and the remaining top quarter s light red. No damage has of yet occurred in this first model. Near the top quarter of this model is a cylindrical device that has just begun to come in contact with the post itself.

The second image shows the same post, the cylindrical device having already impacted the structure, forcing the top half of the post to lean to the right hand side of the diagram. A small gap has begun to form a short way down into the green colored section of the post. The recorded time on this diagram reads Time = 9.9975.

The third image in this set shows the same post, the cylindrical device having impacted the structure more fierce, forcing the post to lean considerably to the right hand side of the diagram.

The top half of the post now leans at a rough forty-five degree angle from its original position, making a considerably larger gap in the initial fracture of the post. The fracture itself appears jagged near the backside of the split. The recorded time on this diagram reads Time = 40.

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Figure 70. Energy of post parts for fast bogie simulation. Graph.

This graph shows four distinct lines. The first line is colored pink and is labeled A 402 Aptek. The second line, black is labeled B 403 Aptek. The third line, blue is labeled C 402 UNL. Finally, the fourth line, red is labeled D 403 UNL. The vertical axis of this graph ranges from zero to 2 and represents Internal Energy (E plus 3) while the horizontal axis of this graph ranges from zero to 40 and represents Time. All four lines begin at the point of zero on both axes. Lines A and C follow suit and rise from their starting points to 0.48 on the vertical axis and 3 on the horizontal axis where they both run in a nearly straight line across the remainder of the graph, leaving it at the point of 0.49 on the vertical and 40 on the horizontal axis. Lines B and D follow suit, spiking upward from their starting point to 1.25 on the vertical axis and 4 on the horizontal axis, where the two lines split and line D continues to ascend higher on the graph than line B. Line B ascends and leaves the graph at the point of 1.5 on the vertical axis and 40 on the horizontal axis while line D ascends and leaves the graph at the point of 1.55 on the vertical and 40 on the horizontal axis.

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Figure 71. Section forces through post just below impact: Fast bogie simulation. Graph.

This graph shows two distinct lines. The first line is colored red and is labeled A5 Aptek while the second line is colored blue and is labeled B5 UNL. The vertical axis of this graph ranges from negative 10 to positive 50 and represents X-force in kilonewtons while the horizontal axis of this graph ranges from zero to 40 and represents Time in milliseconds. Both lines begin at the point of zero on both axes. From there they spike to the point of 45 on the vertical axis and 2 on the horizontal axis and then drop to 26 on the vertical axis and 3 on the horizontal axis. The lines then spike again to 46 on the vertical axis and 5 on the horizontal axis before then drop again to the point of 10 on the vertical axis and 10 on the horizontal axis. From there the two lines oscillate across the graph, the blue line a little heavier than the red line, before both lines leave the graph at the point of 2 on the vertical axis and 40 on the horizontal axis.

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Figure 72. Stress-strain behavior of single elements. Graphs.

Variation by grade.

This graph shows three distinct lines. The first line is solid red and is labeled A 1 Default while the second line is solid pink and is labeled B DS-65. Finally the third line is solid blue and is labeled C Clear. The vertical axis of this graph ranges from 0 to 0.1 and is labeled Effective Stress (v-m (von-mises))(gigapascals) while the horizontal line ranges from 0 to 0.06 and represents Z-strain. All three lines begin at the points of zero on both the vertical and horizontal axes. The red line rises steeply to the points of 0.04 on the vertical axis and 0.005 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.05 on the horizontal axis. The pink line rises steeply to the points of 0.065 on the vertical axis and 0.05 on the horizontal axis where it too slopes down to the points of zero on the vertical axis and 0.05 on the horizontal axis. The blue line rises steeply to the points of 0.083 on the vertical axis and 0.008 on the horizontal axis where it slopes down to the points of zero on the vertical axis 0.05 on the horizontal axis.

Variation by moisture.

This graph shows four distinct lines. The first line is solid red and is labeled A 90 percent default while the second line is solid pink and is labeled B 20 percent. The third line is solid blue and is labeled C 10 percent and the fourth and final line is solid black and is labeled D 1 percent. The vertical axis of this graph ranges from 0 to 0.1 and is labeled Effective Stress (v-m (von-mises))(gigapascals) while the horizontal line ranges from 0 to 0.06 and represents Z-strain. All four lines begin at the points of zero on both the vertical and horizontal axes. The red line rises steeply to the points of 0.04 on the vertical axis and 0.005 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.05 on the horizontal axis. The pink line rises steeply to the points of 0.045 on the vertical axis and 0.03 on the horizontal axis where it too slopes down to the points of zero on the vertical axis and 0.05 on the horizontal axis. The blue line rises steeply to the points of 0.065 on the vertical axis and 0.023 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.023 on the horizontal axis. The black line rises steeply to the points of 0.04 on the vertical axis and 0.005 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.027 on the horizontal axis

Variation by temperature.

This graph shows four distinct lines. The first line is solid red and is labeled A 30 while the second line is solid pink and is labeled B 20 default. The third line is solid blue and is labeled C 10 and the fourth and final line is solid black and is labeled D 1. The vertical axis of this graph ranges from 0 to 0.1 and is labeled Effective Stress (v-m (von-mises))(gigapascals) while the horizontal line ranges from 0 to 0.06 and represents Z-strain. All four lines begin at the points of zero on both the vertical and horizontal axes. The red line rises steeply to the points of 0.037 on the vertical axis and 0.005 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.06 on the horizontal axis. The pink line rises steeply to the points of 0.04 on the vertical axis and 0.003 on the horizontal axis where it too slopes down to the points of zero on the vertical axis and 0.05 on the horizontal axis. The blue line rises steeply to the points of 0.043 on the vertical axis and 0.003 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.025 on the horizontal axis. The black line rises steeply to the points of 0.045 on the vertical axis and 0.005 on the horizontal axis where it slopes down to the points of zero on the vertical axis and 0.01 on the horizontal axis.

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Figure 73. Volumetric behavior of single elements. Graphs.

Variation by grade.

This first graph shows three distinct lines. The first is solid red and is labeled A 1 default while the second line is solid pink and is labeled B DS-65. The third and final line is solid blue and is labeled C Clear. The vertical axis of this graph ranges from 15 to 16.6 and represents Volume (millimeters cubed)(E plus 3) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of 15.6 on the vertical axis and zero on the horizontal axis. The three lines run across the graph diagonally, nearly parallel with each other. The red line peaks at the points of 16.35 on the vertical axis and 49 on the horizontal axis where it drops straight down and off the graph. The pink line peaks at the points of 16.4 and 53 on the horizontal axis where it drops straight down and off the graph. The blue line peaks at the points of 16.45 on the vertical axis and 54 on the horizontal axis where it drops straight down and off the graph.

Variation by moisture.

This second graph shows four distinct lines. The first is solid red and is labeled A 30 percent default. The second line is solid pink and is labeled B 20 percent while the third line is solid blue and is labeled C 10 percent. Finally, the fourth line is solid black and is labeled D 1 percent. The vertical axis of this graph ranges from 15 to 16.6 and represents Volume (millimeters cubed)(E plus 3) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of 15.6 on the vertical axis and zero on the horizontal axis. The three lines run across the graph diagonally, nearly parallel with each other. The red line peaks at the points of 16.35 on the vertical axis and 49 on the horizontal axis where it drops straight down and off the graph. The pink line peaks at the points of 16.05 on the vertical and 32 on the horizontal axis where it drops straight down and off the graph. The blue line peaks at the points of 15.95 on the vertical axis and 24 on the horizontal axis where it drops straight down and off the graph. The solid black line peaks at the points of 16.03 on the vertical axis and 28 on the horizontal axis where it drops straight down and off the graph.

Variation by temperature.

This third graph shows four distinct lines. The first is solid red and is labeled A 30 default. The second line is solid pink and is labeled B 20 default while the third line is solid blue and is labeled C 10. Finally, the fourth line is solid black and is labeled D 1. The vertical axis of this graph ranges from 15 to 16.6 and represents Volume (millimeters cubed) (E plus 3) while the horizontal axis of this graph ranges from 0 to 60 and represents Time (milliseconds). All three lines begin at the points of 15.6 on the vertical axis and zero on the horizontal axis. The three lines run across the graph diagonally, nearly parallel with each other. The red line peaks at the points of 16.58 on the vertical axis and 59 on the horizontal axis where it drops straight down and off the graph. The pink line peaks at the points of 16.39 on the vertical axis and 49 on the horizontal axis where it drops straight down and off the graph. The blue line peaks at the points of 15.99 on the vertical axis and 26 on the horizontal axis where it drops straight down and off the graph. The solid black line peaks at the points of 15.75 on the vertical axis and 9 on the horizontal axis where it drops straight down and off the graph.

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Figure 74. Static post models. Diagrams.

Without neoprene.

This diagram shows a long rectangular column, standing on end, either side of it encased with two wide braces, colored brown. The column itself varies in color. The majority of the column is colored a dark red and is labeled Part 8000 (post). Near the top of the column a small section is colored a light blue and is labeled Part 8001 (post loading area) and has an eye-hook extending out of the left hand side of the structure. Where the column enters the braces, a section is colored a dark green and is labeled Part 8002 (post breaking area). The braces themselves are labeled part 8004 (braces).

With neoprene.

This diagram shows a long rectangular column, standing on end, either side of it encased with two wide braces, colored brown. Protruding from between the column and left-side brace is an extremely narrow rectangular piece. This piece is colored brown and is labeled Part 8008 (neoprene). The column is still mainly colored a dark red. Within the blue section near the top, an eye-hook protrudes from the left-hand side. This is also colored blue and is labeled Part 8003 (loading bolt). At the bottom of the structure, between the column and the left side brace, is a narrow rectangular piece colored purple. This is labeled Part 8006 (steel shim – between brace and post).

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Figure 75. Rounded edge on brace.

This figure shows a close up of a computer-generated diagram of the wooden post inserted into the test brace. It shows one side of the brace, rounded at point of entry.

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Figure 76. Force deflection: Baseline versus test. Graph.

This graph shows three distinct lines. The first line is colored red and is labeled A Baseline. The second is black and is labeled B test Minimum. The third line is blue and labeled C Test Maximum. The vertical axis of this graph ranges from zero to 60 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Deflection in millimeters. All three lines begin at the point of zero on both axes. The first line, line A ascends from zero to 45 on the vertical axis 25 on the horizontal axis where it then drops off to 14 on the vertical axis and 30 on the horizontal axis. From this point the line descends gradually and unevenly across the graph and comes to an end at the point of 8 on the vertical and 185 on the horizontal axis. The second line, line B rises to 45 on the vertical axis and 45 on the horizontal axis where it then descends dramatically across the remainder of the graph, in an uneven fashion and leaves the graph at the points of 7 on the vertical axis and 200 on the horizontal axis. The blue line rises to 55 on the vertical axis and 48 on the horizontal axis where it then descends dramatically and unevenly across the remainder of the graph, leaving the graph at 10 on the vertical axis and 200 on the horizontal axis.

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Figure 77. Energy deflection: Baseline versus test. Graph.

This graph shows three distinct lines. The first line is solid red and is labeled A Baseline while the second line is solid black and is labeled B Test Min. The third line is colored a solid blue and is labeled C Test Max. The vertical axis of this graph ranges from 0 to 6 and represents Energy (kilonewton-millimeters)(E+3) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). All three lines begin at the points of zero on both the vertical and horizontal axes. The red line slopes upward to the points of 2.8 on the vertical axis and 180 on the horizontal axis here it comes to an end. The blue line slopes upward and off the graph at the points of 5.3 on the vertical axis and 200 on the horizontal axis. The black line slopes upward and off the graph at the points of 3.2 on the vertical axis and 200 on the horizontal axis.

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Figure 78. Force deflection: Baseline versus refined mesh. Graph

This graph shows two distinct lines. The first line is colored red and is labeled A Baseline while the second is blue and is labeled B Refined Mesh. The vertical axis of this graph ranges from zero to 50and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Displacement in millimeters. Both lines begin at the points of zero on both axes. Both lines follow suit spiking to the point of 46 on the vertical axis and 30 on the horizontal axis where the red line then drops to 14 on the vertical and the blue line drops to 8 on the vertical both at 7 on the horizontal axis. The red line then spikes slightly and descends across the graph coming to an end at the points of 8 on the vertical axis and 185 on the horizontal axis. The blue line then spikes slightly and descends across the graph coming to an end at the points of 2 on the vertical axis and 185 on the horizontal axis.

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Figure 79. Energy deflection: baseline versus refined mesh. Graph.

This graph shows two distinct lines. The first line is solid red and is labeled A Baseline. The second line is solid blue and is labeled Refined Mesh. The vertical axis of this graph ranges from 0 to 3 and represents Energy (kilonewton-millimeters)(E+3) while the horizontal axis of this graph ranges from 0 to 200 and represents Deflection (millimeters). Both lines begin at the points of zero on both the vertical and horizontal axis. The red line slopes upward and off the graph at the points of 2.75 on the vertical axis and 200 on the horizontal axis. The blue line slopes upward gradually and off the graph at the points of 1.65 on the vertical axis and 200 on the horizontal axis.

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Figure 80. Variations by mesh size: Deformed geometry. Diagrams.

Baseline.

This figure shows two sets of images, each set containing four separate diagrams. The first set is labeled “Baseline”, while the second set is labeled “Refined”.

Baseline.

This first diagram shown in this set shows a three-dimensional close up section of the post, and is labeled 29 millimeters. The post is broken into smaller squares, with the breaking section colored a dark green, approximately ten squares high. In this first diagram, no damage has yet occurred to the post.

The second diagram is labeled 58 millimeters. A small section of squares is shown missing from this diagram approximately three squares deep and the width of the post across. The top half of the post has begun to lean back in the slightest at the point of the break.

The third diagram is labeled 116 millimeters. A slightly larger section is shown missing in this diagram from the latter. The section missing still appears to be roughly three squares deep on the surface, but with a lengthy section missing near the center core of the post. The gap shown at the front of the break appears to be roughly two squares high. The top half of the post is now leaning back a touch further than the latter diagram.

The fourth and final diagram in this set is labeled 189 millimeters. A large section of squares is shown missing from this diagram. The missing section roughly measures five squares deep and the width of the post across. The gap at the beginning of the break has grown i height to nearly three or four squares high, making the top half of the post lean back considerably further from the latter diagram.

Refined.

This first diagram shown in this set shows a three-dimensional close up section of the post, and is labeled 29 millimeters. The post is broken into much smaller squares than the set before, with the breaking section colored a dark green, approximately twenty-five squares high. In this first diagram, no damage has yet occurred to the post.

The second diagram is labeled 58 millimeters. A small section of squares is shown missing from this diagram approximately seven squares deep and the width of the post across. The top half of the post has begun to lean back in the slightest at the point of the break.

The third diagram is labeled 116 millimeters. A slightly larger section is shown missing in this diagram from the latter. The section missing appears to be roughly fourteen deep and the width of the post across. The top half of the post is now leaning back a touch further than the latter diagram.

The fourth and final diagram in this set is labeled 189 millimeters. A large section of squares is shown missing from this diagram. The missing section roughly measures eighteen squares deep, leaving only a section of two or three squares holding the top half section to the bottom half section, and the width of the post across. The gap at the beginning of the break has grown in height to nearly three or four squares high, making the top half of the post lean back considerably further from the latter diagram.

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Figure 81. Force-deflection behavior as a function of grade, moisture content, and temperature. Graphs.

Variation by Grade.

This first graph shows three distinct lines. The first line is colored red and is labeled A 1 Default. The second is black and is labeled B DS-65. The third is blue and is labeled C Clear. The vertical axis of this graph ranges from zero to 100 and represents Force in kilonewtons while the horizontal axis ranges from zero to 200 and represents Displacement in millimeters. All three lines begin at the points of zero on both axes. Line A ascends to the point of 44 on the vertical axis and 25 on the horizontal axis where it then descends and comes to an end at the points of 13 on the vertical axis and 185 on the horizontal axis. Line B ascends to 70 on the vertical and 45 on the horizontal axis where it then descends and come to an end at the points of 24 on the vertical axis and 185 on the horizontal axis. Line C ascends to 80 on the vertical and 58 on the horizontal axis where it then descends and comes to an end at the points of 16 on the vertical axis and 185 on the horizontal axis.

Variation by Moisture.

This second graph shows four distinct lines. The first line is colored red and is labeled A 30 percent Default. The second is black and labeled B 20 percent. The third is blue and labeled 10 percent. The fourth and final line is pink and labeled 1 percent. The vertical axis of this graph ranges from zero to 100 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Displacement in millimeters. All four lines begin at the point of zero on both axes. Line A spikes to 43 on the vertical axis and 25 on the horizontal axis where it then drops to 15 on the vertical axis and 35 on the horizontal axis. From this point the line runs unevenly across the graph, descending slightly and comes to an end at 14 on the vertical axis and 190 on the horizontal axis. Line B spikes to the point of 60 on the vertical and 25 on the horizontal axis where it then drops to 16 on the vertical axis and 35 on the horizontal axis. From this point the line runs unevenly across the graph, descending slightly and comes to an end at 16 on the vertical axis and 190 on the horizontal axis. Line C spikes to the point of 95 on the vertical and 25 on the horizontal axis where it then drops to 14 on the vertical axis and 35 on the horizontal axis. From this point the line runs unevenly across the graph, descending slightly and comes to an end at 14 on the vertical axis and 190 on the horizontal axis. Line D spikes to the point of 70 on the vertical and 20 on the horizontal axis where it then drops to zero on the vertical axis and 22 on the horizontal axis. From this point the line runs unevenly across the bottom graph, and comes to an end at 1 on the vertical axis and 190 on the horizontal axis.

Variation by Temperature.

This third graph shows four distinct lines. The first line is colored red and is labeled A 30. The second is black and labeled B 20 default. The third is blue and labeled C 10. The fourth and final line is pink and labeled D 1. The vertical axis of this graph ranges from zero to 100 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Displacement in millimeters. All four lines begin at the point of zero on both axes. Line A ascends to the point of 40 on the vertical axis and 25 on the horizontal axis before dropping to 16 on the horizontal axis where it runs unevenly across the remainder of the graph, descending slightly and coming to an end at the point of 14 on the vertical axis and 190 on the horizontal axis. Line B ascends to the point of 43 on the vertical axis and 25 on the horizontal axis before dropping to 16 on the horizontal axis where it runs unevenly across the remainder of the graph, descending slightly and coming to an end at the point of 15 on the vertical axis and 190 on the horizontal axis. Line C ascends to the point of 45 on the vertical axis and 25 on the horizontal axis before dropping to 16 on the horizontal axis where it runs unevenly across the remainder of the graph, descending slightly and coming to an end at the point of 17 on the vertical axis and 190 on the horizontal axis. Line D ascends to the point of 47 on the vertical axis and 25 on the horizontal axis before dropping to 16 on the horizontal axis where it runs unevenly across the remainder of the graph, descending slightly and coming to an end at the point of 19 on the vertical axis and 190 on the horizontal axis.

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Figure 82. Energy-deflection behavior as a function of grade, moisture content, and temperature. Graphs.

Variation by grade.

This graph shows three distinct lines. The first line is solid red and is labeled A 1 default while the second line is solid black and is labeled B DS-65. The third and final line is solid blue and is labeled C Clear. The vertical axis of this graph ranges from 0 to 6 and represents Energy [kN-millimeters](E+3) while the horizontal axis of this graph ranges from 0 to 200 and represents Displacement (millimeters). All three lines begin at the points of zero on both the vertical and horizontal axes. The red line gradually inclines to the points of 2.75 on the vertical axis and 185 on the horizontal axis where it comes to an end. The black line inclines to the points of 5.85 on the vertical axis and 185 on the horizontal axis where it comes to an end. Finally, the blue line inclines to the points of 5.25 on the vertical axis and 185 on the horizontal axis where it too finds its end.

Variation by moisture.

This graph shows four distinct lines. The first line is solid red and is labeled A 30 percent default. The second line is solid black and is labeled B 20 percent while the third line is solid blue and is labeled C 10 percent. The fourth and final line is solid pink and is labeled D 1 percent. All four lines begin at the points of zero on both the vertical and horizontal axes. The red line slopes upward gradually to the points of 2.75 on the vertical axis and 185 on the horizontal axis where it comes to an end. The black line slopes upward to the points of 3.25 on the vertical axis and 185 on the horizontal axis where it finds its end while the blue line slopes up to the points of 2.72 on the vertical axis and 185 on the horizontal axis where it comes to an end. Finally, the pink line slopes up to the points of .075 on the vertical axis and .025 on the horizontal axis where the line plateaus and runs nearly parallel with the horizontal axis until it comes to an end at the points of .075 on the vertical axis and 185 on the horizontal axis.

Variation by temperature.

This graph shows four distinct lines. The first line is solid red and is labeled A 30. The second line is solid black and is labeled B 20default while the third line is solid blue and is labeled C 10. The fourth and final line is solid pink and is labeled D 1. All four lines begin at the points of zero on both the vertical and horizontal axes. The red line slopes upward gradually to the points of 2.5 on the vertical axis and 185 on the horizontal axis where it comes to an end. The black line slopes upward to the points of 2.75 on the vertical axis and 185 on the horizontal axis where it finds its end while the blue line slopes up to the points of 2.5 on the vertical axis and 185 on the horizontal axis where it comes to an end. Finally, the pink line slopes up to the points of 2 on the vertical axis and 185 on the horizontal axis where the line comes to an end.

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Figure 83. Variation by grade: Deformed geometry. Diagrams.

This figure shows three sets of diagrams, each set containing four images. The first set of images is labeled 1 Default. The second set of images is labeled DS-65. And the remaining set of images is labeled Clear.

1 Default.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 116 millimeters. The image shows the computer generated three-dimensional column. Three solid rows of squares are still missing from the mid-point along with a group of squares through the middle of the gap. The column appears to be leaning more significantly to the left.

The fourth image in this set is labeled 189 millimeters. The image shows the computer generated three-dimensional column. Two addition rows of squares are shown missing in this image with the top have of the column leaning to the left considerably now.

DS-65.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows two solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image is labeled 116 millimeters. The image shows the computer generated three-dimensional column. Two rows of squares are still shown missing, however the top row of squares above the missing gap is shown jagged and uneven as the top half of the column leans further to the left.

The fourth image is labeled 188 millimeters. . The image shows the computer generated three-dimensional column. Two rows of squares are still shown missing, however the jagged gap is now more pronounced, the edges shown at a sharper angle as the top half of the column leans to the left considerably.

Clear.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 29 millimeters. The image shows the computer generated three-dimensional column. There appears only a small dent at the mid-point of the column on the left-hand side of the structure. No other damage is apparent.

The third image is labeled 115 millimeters. The image shows the computer generated three-dimensional column. Two rows of squares are shown missing, however the top row of squares above the missing gap is shown jagged and uneven as the top half of the column leans further to the left.

The fourth image is labeled 188 millimeters. The image shows the computer generated three-dimensional column. The damage to the mid-point of the column appears to be the same, as above, though the top half of the column does not appear to be leaning to left as much as prior.

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Figure 84. Variation by moisture content: Deformed geometry. Diagrams.

This figure shows four sets of images, each set containing four separate images. The first set of images is labeled 30 percent default. The second set is labeled 20 percent. The third set is labeled 10 percent. And finally, the fourth set is labeled 1 percent.

30 Percent Default.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 116 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing, however, the top half of the column does not appear to be leaning as it did prior.

The fourth image in this set is labeled 189 millimeters. Three solid rows of squares are still missing from the mid-point along with a group of squares through the middle of the gap. The column appears to be leaning more significantly to the left.

20 Percent.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 116 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. Four rows of squares now appear to be missing with a few squares located near the back of the gap looking jagged and rough. The top half of the column appears to be leaning further to the left.

The fourth image in this set is labeled 189 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. Six rows of squares are now shown missing and the top half of the column leans considerably to the left, forcing the gap to open wide.

10 Percent.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares. Four rows are shown missing from the mid-point of the column, however the top half does not appear to be leaning at all.

The second image in this set is labeled 59 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column now shows five solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 116 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column now leans more to the left, with only two rows of squares left at the mid-point, hinging the upper and lower halves together.

The fourth image in this set is labeled 190 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column now leans considerably to the left, the gap widened, with only two rows of squares left at the mid-point, hinging the upper and lower halves together.

1 Percent.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares. All but one row of squares is shown missing from the mid-point of the column, with the top half of the column leaning back ever so slightly. The break appears clean.

The second image in this set is labeled 59 millimeters. The image shows the computer generated three-dimensional column. The top half of the column leans further to the left in this image, a single row of squares remaining, holding the upper and lower half of the column together.

The third image in this set is labeled 117 millimeters. The image shows the computer generated three-dimensional column. The top half of the column leans further to the left in this image, a single row of squares remaining, holding the upper and lower half of the column together.

The fourth image in this set is labeled 190 millimeters. The image shows the computer generated three-dimensional column. A single row of squares appears to be hinging the upper and lower halves of the column together, though the gap appears to have lessened in this image.

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Figure 85. Variation by temperature: Deformed geometry. Diagrams.

This figure shows four sets of images, each set containing four separate images. The first set of images is labeled 30 Degrees Celsius. The second set is labeled 20 Degrees Celsius Default. The third set is labeled 10 Degrees Celsius. And finally, the fourth set is labeled 1-Degree Celsius.

30 Degrees Celsius.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 115 millimeters. The image shows the computer generated three-dimensional column. Three solid rows of squares are still missing from the mid-point along with a group of squares through the middle of the gap. The column appears to be leaning more significantly to the left.

The fourth image in this set is labeled 188 millimeters. The image shows the computer generated three-dimensional column. Five rows of squares now appear to be missing, and the top half of the column leans to the left significantly.

20 Degrees Celsius Default.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 116 millimeters. The image shows the computer generated three-dimensional column. Three solid rows of squares are still missing from the mid-point along with a group of squares through the middle of the gap. The column appears to be leaning more significantly to the left.

The fourth image in this set is labeled 188 millimeters. The image shows the computer generated three-dimensional column. Five rows of squares now appear to be missing, and the top half of the column leans to the left significantly.

10 Degrees Celsius.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows a computer generated three-dimensional column as mentioned prior. The mid-point of the column shows three solid rows of squared missing and the top half of the column appears to be leaning to the left slightly.

The third image in this set is labeled 115 millimeters. The image shows the computer generated three-dimensional column. Three solid rows of squares are still missing from the mid-point along with a group of squares through the middle of the gap. A few squares are also shown missing from the front surface of the column near the back end of the gap. The column appears to be leaning more significantly to the left.

The fourth image in this set is labeled 189 millimeters. The image shows the computer generated three-dimensional column. Three solid rows of squares are still missing from the mid-point along with a group of squares through the middle of the gap. A few squares are also shown missing from the front surface of the column near the back end of the gap. The column now leans to the left considerably.

1-Degree Celsius.

The first image in this set is labeled 29 millimeters. The image shows a computer generated three-dimensional column. The top quarter of the column and the lower quarter are colored red while the distance between is colored green. The column itself is made up of many small squares.

The second image in this set is labeled 58 millimeters. The image shows the computer generated three-dimensional column. The top half of the column appears to be leaning to left slightly, as a jagged gap is formed near the mid-point of the column itself. Two rows of squares are shown missing from the tip of the gap. The rest of the squares grow jagged, almost stair-like as the gap opens near the back.

The third image in this set is labeled 115 millimeters. The image shows the computer generated three-dimensional column. The top half of the column appears to be leaning to left more considerably, as a jagged gap is formed near the mid-point of the column itself. Two rows of squares are still shown missing from the tip of the gap. The rest of the squares grow jagged, almost stair-like as the gap opens near the back.

The fourth image in this set is labeled 189 millimeters. The image shows the computer generated three-dimensional column. The top half of the column appears to be leaning to left more considerably, as a jagged gap is formed near the mid-point of the column itself. Two rows of squares are still shown missing from the tip of the gap. The rest of the squares grow jagged, almost stair-like as the gap opens near the back.

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Figure 86. Dynamic wood post test model. Diagram.

This diagram shows a computerized block skeleton of a vehicle, with an extended arm at the front bumper. The arm has a cylindrical structure attached to it lengthwise. This structure itself is pressing against a rectangular column, embedded in an even larger column.

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Figure 87. Post vaporization. Diagrams.

This figure shows a sequence of four individual computer generated illustrations.

The first illustration shows a three dimensional, rectangular post embedded in a frame of sorts. The post itself is colored dark blue while the frame is colored a dark red. The post is being impacted near its top left-hand side by a cylindrical device. The impact is recorded at a time equaling zero. No damage has as of yet resulted to the post due to impact.

The second illustration shows the same rectangular post structure, now with the slightest indent at the point of impact from the cylindrical device. The point at which the post is embedded in the frame has been compromised, a split occurring along that line from left to right as the post leans to the right. The impact is recorded at a time equaling 10.501.

The third illustration shows the same rectangular post structure angled to the right only a fraction more from the previous illustration. However, the structure has begun to disintegrate, leaving only large fragments of itself from the point in which it is embedded into the frame to the point in which initial contact with the cylindrical device has taken place. The impact is recorded at a time equaling 10.736.

The fourth illustration shows the same rectangular post structure. The body of the structure has disintegrated even further in this illustration, only the slightest fragments now visible from the point in which the structure is embedded into the frame to the point above the point in which the cylindrical device has impacted the post. The impact is recorded at a time equaling 10.845.

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Figure 88. Contact at sharp corner. Diagrams.

This figure shows four separate images.

The first image shows a computer-generated illustration of a wooden post embedded into neoprene lined concrete base. The post is colored blue in this illustration and the base is colored red. The impact vehicle is shown just making contact with the post. No damage is visible as of yet. The time recorded on this image reads Time equals 0.

The second image shows the wooden post splitting at the point in which it is embedded in the concrete base. The break appears clean as the post leans at a rough twenty-five degree angle to the right, with the impact vehicle in direct contact with the left-hand side of the structure. The time recorded on this image reads time equals 29.999.

The third image shows the wooden splitting further, the break appearing slightly jagged near the back of the back as the post leans at a rough forty-five degree angle, with the impact vehicle still in contact with the left-hand side of the structure. The time recorded on this image reads Time equals 49.997.

The fourth image shows a computer-generated close-up illustration of the wooden post at the point in which it is embedded into the concrete base. The image shows the gap, appearing to be a clean break as the post leans to the right. The edge of the concrete however, appears to be digging into the right hand side of the structure as it leans.

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Figure 89. Contact at sharp corner. Diagrams.

This figure shows four separate images.

The first image shows a computer-generated illustration of a wooden post embedded into neoprene lined concrete base. The post is colored blue in this illustration and the base is colored red. The impact vehicle is shown just making contact with the post. No damage is visible as of yet. The time recorded on this image reads Time equals 0.

The second image shows the wooden post splitting at the point in which it is embedded in the concrete base. The break appears clean as the post leans at a rough twenty-five degree angle to the right, with the impact vehicle in direct contact with the left-hand side of the structure. The time recorded on this image reads time equals 29.999.

The third image shows the wooden splitting further, the break appearing slightly jagged near the back of the back as the post leans at a rough forty-five degree angle, with the impact vehicle still in contact with the left-hand side of the structure. The time recorded on this image reads Time equals 49.997.

The fourth image shows a computer-generated close-up illustration of the wooden post at the point in which it is embedded into the concrete base. The image shows the gap, appearing to be a clean break as the post leans to the right. The edge of the concrete however, appears to be digging into the right hand side of the structure as it leans.

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Figure 90. Contact Penetrations. Diagrams.

This figure shows two separate images.

The first image shows a computer-generated illustration of a wooden post with a close-up view at the point in which it is embedded into the concrete. The image focuses on the rounded sleeve inserted against the bending side of the post. The post is shown in the color red, while the sleeve used is shown in blue, curved outward at the point of entry.

The second image shows the same illustration, with the post now leaning to the right and side, against the embedded sleeve. The post appears to be breaking through the sleeve, embedding itself into its surface.

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Figure 91. Improved Contact. Diagram.

This figure shows a computer-generated illustration of a wooden post with a close-up view at the point in which it is embedded into the concrete. The image focuses on the rounded sleeve inserted against the bending side of the post. The post in this illustration is shown leaning to the right hand side against the sleeve. The sleeve itself remains unscathed and undisturbed by the bending post.

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Figure 92. Element vaporization at bottom of post. Diagrams.

This figure shows four separate images.

The first image shows a computer-generated illustration of a post, colored in red and broken into a multitude of squares. The front end of the impact vehicle is shown striking the left-hand side of the post, though no damage has occurred as of yet to the post.

The second image shows the computer generated illustration of the post, with the top half of the post leaning ever so slightly to the right hand side, the impact vehicle still in contact with the left-hand side of the structure. The base of the post shows some damage, as the left-left hand side appears to be disintegrating, with a handful of squares now missing for a small part of the structure.

The third image shows the computer generated illustration of the post, with the top half of the post leaning further to the right hand side. A gap has formed near the mid-point of the entire post. The disintegrating blocks at the base of the post have increased, working their way up the left-hand side of the post a short distance from the gap that has now formed.

The fourth image shows the computer generated illustration of the post, with the top half of the post leaning considerably to the right hand side, the gap now open severely. The disintegrating blocks at the base of the post have increased severely, now present up to the point in which the gap has formed, and spreading across the majority of the lower half face of the structure.

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Figure 93. Volume expansion of 75 percent in an element near the bottom of post. Graph.

This graph shows one distinct solid blue line labeled A 12805. The vertical axis of this graph ranges from 14 to 30 and represents Volume (E plus 3) while the horizontal axis of this graph ranges from 0 to 20 and represents Time. The blue line begins at the points of 16 on the vertical axis and zero on the horizontal axis where it runs a jagged line to the points of 16 on the vertical axis and 5 on the horizontal axis. From there the blue line spikes up to the points of 24 on the vertical axis and 7.5 on the horizontal axis where it continues a gradual climb to the points of 26.5 on the vertical axis and 8 on the horizontal axis. The blue line then continues its jagged assent and runs off the graph at the points of 28 on the vertical axis and 20 on the horizontal axis.

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Figure 94. Vaporization with a time step of 0.0001 milliseconds. Diagram.

This figure shows a computer-generated illustration of a post, colored in red and broken into a multitude of squares. The front end of the impact vehicle is shown striking the left-hand side of the post, and the post has begun to lean to the right hand side, with a gap forming near the mid-point of the entire structure. The very bottom of the post is shown completely distorted, with multiply squares missing, the post nearly twisted and jagged.

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Figure 95. Highly distorted elements sometimes do not erode. Diagrams.

The first image in this figure shows a computer-generated illustration of a post. The post is colored blue. No damage to the post is shown in this first image.

The second image shows a computer-generated illustration of a post. A gap has formed at the mid-point of the structure. Fringe levels are indicated at the back of the gap in red and running up the side of the gap slightly in light blue and green.

The third image in this figure shows a computer-generated illustration. The gap has deepened. Leaving a strain of post in the middle to stretch from one half to the other, the fringe levels on this piece colored red. The fringe levels on either side of the gap have turned from light blue and green to red and dark green.

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Figure 96. Damage of highly distorted element. Graph.

This graph shows one single line, colored blue and labeled A 19658.  The vertical axis of this graph ranges from 0 to 1.0 while the horizontal axis of this graph ranges from 0 to 40 and represents Time (milliseconds).  The blue line begins at the points of zero on both the vertical and horizontal axes where it runs along the horizontal axis to the point of 5 before it begins its assent.  The blue line then climbs nearly vertically to the points of 0.98 on the vertical axis and 6 on the horizontal axis where it plateaus and runs in a straight line off of the graph leaving it at the points of 0.98 on the vertical axis and 40 on the horizontal axis.

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Figure 97. SYP Grade 1. Diagram.

This figure shows a close up section of a computer-generated illustration of a post. The middle section of this illustration is colored green while the top and lower quarters are colored red. A gap has formed near the midsection of the post, as the top half leans considerably to the right hand side. The gap itself appears jagged and uneven.

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Figure 98. SYP Grade 1. Diagram.

This figure shows a close up section of a computer-generated illustration of a post. The middle section of this illustration is colored green while the top and lower quarters are colored red. A gap has formed near the midsection of the post, as the top half leans considerably to the right hand side. The gap itself appears jagged and uneven.

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Figure 99. SYP Grade 1. Diagram.

This figure shows a close up section of a computer-generated illustration of a post. The middle section of this illustration is colored green while the top and lower quarters are colored red. The top half of the post is leaning to the right hand side, creating a large gap, which has formed near the midsection of the post and nearly runs the width of the post. The gap appears to be a clean break, with even edges and sides.

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Figure 100. SYP Grade DS-65.

This figure shows a close up section of a computer-generated illustration of a post. The middle section of this illustration is colored green while the top and lower quarters are colored red. The top half of the post is leaning to the right hand side, creating a gap, which has formed near the midsection of the post. The upper mouth of the gap appears jagged, and the gap itself is small, running through not even half of the width of the post.

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Figure 101. SYP Grade DS-65.

Fracture of wood.

This diagram shows two separate images. The first image is a brown colored square. At each corner on both the left and right hand side of the square there exists an arrow pointing away from the image.

Specimens break in two.

This second image shows two halves of the first image separate from each other with a dotted outline of the original image between them. The left hand corners of the left hand half exhibit the same arrows as the previous image as do the right hand corner of the right hand image.

Finite element simulation.

This diagram shows two separate images. The first image is a brown colored square. At each corner on both the left and right hand side of the square there exists an arrow pointing away from the image.

Element stretches.

This daigram shows an elongated rectangle colored brown. The rectangle’s center is surrounded by a dotted outline of a square. At each corner on both the left and right hand side of the rectangle there exists an arrow pointing away from the image.

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Figure 102. Demonstration of void formation and crushing of wood specimens. Images.

Void Formation superscript 12.

This figure shows an image of a cross section of wood. The grain runs in small arcs lengthwise in the image, with small fractures occurring near the mid point of the photograph.

Pore Compaction superscript 12.

This figure shows a cross section of wood magnified. The upper half of the image shows clusters of small circles, looking considerably like cells or a honeycomb. The lower half of the image shows a variety of streaks running lengthwise in the image.

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Figure 103. User’s grades 1 and 1D simulation compared with performance envelopes, using GF || = 50 G F ⊥ Graph.

This graph shows three distinct lines. The first line is colored red and is labeled A Baseline. The second is black and is labeled B test Minimum. The third line is blue and labeled C Test Maximum. The vertical axis of this graph ranges from zero to 60 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Deflection in millimeters. All three lines begin at the point of zero on both axes. The first line, line A ascends from zero to 45 on the vertical axis 25 on the horizontal axis where it then drops off to 14 on the vertical axis and 30 on the horizontal axis. From this point the line descends gradually and unevenly across the graph and comes to an end at the point of 8 on the vertical and 185 on the horizontal axis. The second line, line B rises to 45 on the vertical axis and 45 on the horizontal axis where it then descends dramatically across the remainder of the graph, in an uneven fashion and leaves the graph at the points of 7 on the vertical axis and 200 on the horizontal axis. The blue line rises to 55 on the vertical axis and 48 on the horizontal axis where it then descends dramatically and unevenly across the remainder of the graph, leaving the graph at 10 on the vertical axis and 200 on the horizontal axis.

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Figure 104. Most of the grades 1 and 1D static post test measurements exhibit brittle behavior. Graphs.

These two graphs show 15 test data curves, with seven curves (Tests 712, 563, 113, 1223, 223, 1063, and 1019) on the first graph and eight curves (Tests 1201, 1124, 1073, 308, 718, 1323, 652, and 418) on the second graph. The x-axes are deflection in inches between 0 and 10 (0 and 254 mm). The y-axes are force in kips between 0 and 20 kips (0 and 90 kN). On the first graph subtitled Set 1, four curves (563, 113, 1223, 223) increase in force from 0 to between 9.5 and 11.5 kips over 1.3 inches in deflection, followed by sudden drop in force indicative of sudden post failure (as well as gage failure). The fifth curve increases in force from 0 to 12.5 kips over 1.8 inches, followed by sudden failure. The remaining two curves exhibit a more ductile behavior. One curve (1019) reaches a peak force of approximately 12.5 kips in two inches, then maintains that force until 3.1 inches, followed by a gradual reduction in strength to 4 kips at 8 inches. The other curve (712) reaches a peak force of approximately 16 kips in 3 inches, then maintains that force until 4.4 inches, followed by sudden failure. On the second graph subtitled Set 2, three curves (1201, 718, and 1124) increase in force from 0 to about 9 kips over 1.3 to 1.5 inches in deflection, followed by sudden drop in force indicative of sudden post failure. Two curves (1323 and 652) increases in force from 0 to 10 kips over 1.5 inches, followed by a more gradual increase in force to 11 kips by 2.7 inches, followed by sudden failure. One curve (418) increases in force from 0 to 13.2 kips in 1.9 inches followed by sudden failure. The remaining two curves exhibit a more ductile behavior. One curve (1201) reaches a peak force of approximately 8 kips in two inches, then maintains that force until 4.3 inches, followed by failure. The other curve (1073) reaches a peak force of approximately 5 kips in 1.5 inches, then maintains that force until 4.3 inches, followed by gradual failure.

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Figure 105. Good correlation is achieved between the simulation and performance envelopes by increasing the fracture energy above the default value (to Gf || = 250 Gf ⊥). Graph.

This graph shows three distinct lines. The first line is solid black and is labeled LS-DYNA Calculation. The second line is blue dotted and is labeled Grade 1 Test 418. The third and final line is colored solid blue and is labeled Performance Envelopes. The vertical axis of this graph ranges from zero to 75 and represents Force in kilonewtons while the horizontal axis of this graph ranges from zero to 200 and represents Deflection in millimeters. All three lines begin at the points of zero on both axes. The first line, solid black rises in a slope to 45 on the vertical axis and 45 on the horizontal axis where it then slope down unevenly and leaves the graph at 5 on the vertical axis and 200 on the horizontal axis. The second line, blue dotted, rises in a slope to 42 on the vertical axis and 45 on the horizontal axis where it then slope down unevenly and leaves the graph at 8 on the vertical axis and 200 on the horizontal axis. The third line, solid blue, rises unevenly and peaks at 58 on the vertical axis and 45 on the horizontal axis where it then descends very unevenly and leaves the graph at 7 on the vertical axis and 200 on the horizontal axis.

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Figure 106. A DS-65 pine post modeled with simple pinned boundary conditions. Diagrams.

Without modeling rate effects.

This first figure shows a computer-generated illustration of a post being struck on its upper left-hand side by the impact vehicle. The top half of the post is colored a light green, while the lower quarter is colored a dark blue. The post has split due to impact where the green section meets the blue section, and the top half of the post leans considerably to the right. The split has caused a gap to form and a fracture to run lengthwise up a small portion of the post, while the back half of the post remains in tact and appears to be bending beneath the stress of the impact.

With modeling rate effects.

This first figure shows a computer-generated illustration of a post being struck on its upper left-hand side by the impact vehicle. The top half of the post is colored a light green, while the lower quarter is colored a dark blue. The post has split due to impact where the green section meets the blue section. The top half of the post has become completely severed from the lower half, each section of the split appearing jagged and rough.

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Figure 107. Developer static post simulations using hourglass stiffness type 4 with a reduced (o.o3) coefficient. Diagrams and graphs.

Wood Material model.

Diagram.

This figure shows a computer-generated illustration of a post. The top half of the post is colored purple and is labeled Loaded Region. The lower half is broken into three sections. The first section, making up the upper quarter of the post is colored red. The section below it is a small section, shows just a line colored orange and is labeled Break Region. The lower quarter of the illustration is colored a light green. A small section has been removed from just below the Break Region creating a small gap in the left-hand side of the post.

Graph.

This graph shows five distinct lines. The first line is blue and is labeled C. The next line is colored pink and is labeled D. The next line is green and is labeled A. The next line is colored yellow and is labeled X. Finally, the last line is colored dark blue and is labeled B. The vertical axis of this graph ranges from zero to 30 and represents Hourglass to Internal Energy Ratio in Percentage. The horizontal axis of this graph represents Time.

The first line, the blue line labeled C begins at the point of 3 percent and spikes to 10 percent before gradually increasing to the point of 14 percent. From this point, the line oscillates as it descends and leaves the graph at 10 percent.

The second line, pink line labeled D begins at the point of zero percent and spikes to the point of 8 percent where it gradually ascends to 10 percent before oscillating off the graph at 10 percent.

The third line, the green line labeled A begins at the point of 20 percent before dropping considerably to the point of 6 percent, where it gradually ascends to 10 percent. From this point the line oscillates as it descends considerably and leaves the graph at 4 percent.

The fourth line, the yellow line labeled X begins at the point of zero percent and ascends to the point of 6 percent. From this point the line oscillates off the graph at 4 percent.

The final line, the dark blue line labeled B begins at the point of zero. From this point the dark blue line rises in a straight line to 2 percent before oscillating off the graph at the point of 2 percent.

Elastic Material model.

Diagram.

This figure shows a computer-generated illustration of a post. The top half of the post is colored purple and is labeled Loaded Region. The lower half is broken into three sections. The first section, making up the upper quarter of the post is colored red. The section below it is a small section, shows just a line colored orange and is labeled Break Region. The lower quarter of the illustration is colored a light green. The post leans slightly to the right, however no visible damage is apparent. The post bent but not split or broken.

Graph.

This graph shows five distinct lines. The first line is blue and is labeled C. The next line is colored pink and is labeled D. The next line is green and is labeled A. The next line is colored yellow and is labeled X. Finally, the last line is colored dark blue and is labeled B. The vertical axis of this graph ranges from zero to 45 and represents Hourglass to Internal Energy Ratio. The horizontal axis of this graph represents Time.

The first line, the blue line labeled C begins at the point of zero before spiking to the point of 15. The blue line then drops to the point of 10 before returning to the point of 15 where it runs straight across and off of the graph.

The second line, the pink line labeled D begins at the point of zero and ascends to the point of 5 where it then runs across and off of the graph in a straight line.

The third line, the green line labeled A begins at the point of 25 where it descends as it oscillates to the point of 5. From this point, the line straightens and runs across and off the graph at the point of 5.

The fourth line, the yellow line labeled X, and the fifth line, the line colored dark blue and labeled B both begin at the point of zero. From this point both line ascend to 5 where they runs in a straight line across and off the graph at the point of 5.

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Figure 108. Finite element meshes used in demonstration problems. Diagrams.

Single Flap.

This figure shows computer-generated illustration of a post embedded in a concrete brace, showing distinctly the neoprene lining used on either side of the post.  The left-hand side of the post shows the neoprene flap, exiting the concrete brace and folded over slightly.  The neoprene on the right hand side is cut even with the insertion point of the post into the concrete base.

Double Flap.

This figure shows computer-generated illustration of a post embedded in a concrete brace, showing distinctly the neoprene lining used on either side of the post.  The left and right hands sides of the post show the neoprene flap, exiting the concrete brace and folded over slightly.

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Figure 109. Stable behavior in developer single flap calculation. Diagrams.

0.0 milliseconds. 

This figure shows a computer-generated illustration of a post, embedded in a concrete brace using the single neoprene flap.  The majority of the post is colored red, with a small section near the top colored blue, representing the impact point and a small section at mid-point on the post representing the breaking area.  This latter area is also the area in which the post is embedded into the concrete base.  This first figure shows the impact vehicle making contact with the post, though no damage has as of yet occurred.

30 milliseconds.

This figure shows the top half of the post leaning to the right hand side as a gap forms in the green section of the post from the resulting impact.  The top half leans at a rough twenty-five degree angle from its original position.

50 milliseconds.

This figure shows the top half of the post leaning considerably more, the gap near the midsection widening as the post now leans at a rough forty-five degree angle.

100 milliseconds.

This figure shows the top half of the post laying nearly parallel with the ground, the gap fully open, the top half of the post being held onto the bottom by only a fraction of the remaining post.

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Figure 110. Unstable behavior in developer double flap calculation. Diagrams.

0.0 milliseconds.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the double neoprene flaps. The majority of the post is colored yellow, with a small section near the top colored red, representing the impact point and a small section at mid-point on the post representing the breaking area. This latter area is also the area in which the post is embedded into the concrete base. This first figure shows the impact vehicle making contact with the post, though no damage has as of yet occurred.

10.752 milliseconds.

This figure shows the top half of the post leaning to the right hand side as a small gap forms in the red “breaking section” section of the post from the resulting impact. The top half leans at a rough ten-degree angle from its original position.

10.785 milliseconds.

This figure shows the post leaning at the same as previously mentioned. The small gap still exists, its position found just beneath the level in which the neoprene sleeve exits the concrete brace. A large section of the post has disintegrated, beginning in the red “breaking area” section and running up to a point just below the impact area. The disintegration has cause a large chunk to be missing from the post, nearly the width of the structure.

11.0 milliseconds.

This figure shows what remains of the post. Only a fraction of the post remains up near the impact area, literally just scattering of the structure remain. The post remains fully intact below the embedded area, but the rest of the post has evaporated.

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Figure 111. Unstable behavior in the user's single flap calculation. Diagrams.

This figure shows a sequence of four individual computer generated illustrations.

The first illustration shows a three dimensional, rectangular post embedded in a frame of sorts.  The post itself is colored dark blue while the frame is colored a dark red.  The post is being impacted near its top left-hand side by a cylindrical device. No damage has as of yet resulted to the post due to impact.

The second illustration shows the same rectangular post structure, now with the slightest indent at the point of impact from the cylindrical device. The point at which the post is embedded in the frame has been compromised, a split occurring along that line from left to right as the post leans to the right. The third illustration shows the same rectangular post structure angled to the right only a fraction more from the previous illustration.  However, the structure has begun to disintegrate, leaving only large fragments of itself from the point in which it is embedded into the frame to the point in which initial contact with the cylindrical device has taken place. The fourth illustration shows the same rectangular post structure.  The body of the structure has disintegrated even further in this illustration, only the slightest fragments now visible from the point in which the structure is embedded into the frame to the point above the point in which the cylindrical device has impacted the post.

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Figure 112. LS-DYNA MESSAG file diagnostics for the stable time step. Instructions.

Single flap.

The LS-DYNA time step size should not exceed 0.235E-02 to avoid contact instabilities. If the step size is bigger then scale the penalty of the offending surface.This LS-DYNA output diagnostic lists the increment number, time, time step, and action (write plot file or flush buffers).The list starts with increment 0 at time 0 and ends with increment 7603 at time 30.003.The time step ranges from 5.01E-03 to 3.33E-03.All time steps exceed the stable value of 2.35E-03.

Double flap.

The LS-DYNA time step size should not exceed 0.235E-02 to avoid contact instabilities. If the step size is bigger then scale the penalty of the offending surface. This LS-DYNA output diagnostic lists the increment number, time, time step, and action (write plot file or flush buffers).The list starts with increment 0 at time 0 and ends with increment 2350 at time 9.9974.The time step ranges from 5.01E-03 to 4.19E-03.All time steps exceed the stable value of 2.35E-03.

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Figure 113. Stable behavior is achieved by reducing the time step to that needed for stable contact surface behavior (default Grade 1 saturated pine properties without rate effect). Diagrams.

0.0 milliseconds.

This figure shows a computer-generated illustration of a post, embedded in a concrete brace using the single neoprene flap. The majority of the post is colored red, with a small section near the top colored blue, representing the impact point and a small section at mid-point on the post representing the breaking area. This latter area is also the area in which the post is embedded into the concrete base. This first figure shows the impact vehicle making contact with the post, though no damage has as of yet occurred.

15 milliseconds.

This figure shows the top half of the post leaning to the right hand side as a gap forms in the green section of the post from the resulting impact. The top half leans at a rough twenty-five degree angle from its original position.

50 milliseconds.

This figure shows the top half of the post leaning considerably more, the gap near the midsection widening as the post now leans at a rough forty-five degree angle.

100 milliseconds.

This figure shows the top half of the post laying nearly parallel with the ground, the gap fully open, the top half of the post being held onto the bottom by only a fraction of the remaining post.

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Figure 114. LS-DYNA diagnostics for the stable time step. Instructions.

Control contact.

The LS-DYNA time step size should not exceed 0.235E-02 to avoid contact instabilities. If the step size is (words missing?) bigger then scale the penalty of the offending surface. This LS-DYNA output diagnostic lists the increment number, time, time step, and action (write plot file or flush buffers). The list starts with increment 0 at time 0 and ends with increment 23649 at time 50.002. The time step is 2.11E-03 for all times. The time step does not exceed the stable value of 2.35E-03.

Control timestep.

The LS-DYNA time step size should not exceed 0.235E-02 to avoid contact instabilities. If the step size is (words missing?) bigger then scale the penalty of the offending surface.This LS-DYNA output diagnostic lists the increment number, time, time step, and action (write plot file or flush buffers). The list starts with increment 0 at time 0 and ends with increment 31210 at time 50.001. The time step ranges between 2.23E-03 and 1.37E-03. These time steps do not exceed the stable value of 2.35E-03.

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Figure 115. Unstable behavior of an elastic element in the neoprene liner. Diagrams.

Post with liners.

This figure shows a computer-generated illustration of a post with a liner on either side of it. The liner on the left-hand side of the post is colored blue. At the base of the liner is a sharp protruding object, sticking out from the side of the liner at a rough forty-five degree angle.

View of liner.

This figure shows a close-up of the liner. At the base of the liner is a sharp protruding object, sticking out from the side of the liner at a rough forty-five degree angle.

View of post.

This figure shows a close-up of t a post. The image is computer-generated three-dimensional representation. The post is colored green.

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Figure 116. The liner penetrates the post when the post modeled with either elastic or wood material models. Diagrams.

Elastic material #1 post.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the single flap method. The post itself leans to the right a degree though no break or split has occurred. The post is simply bent over the side right hand side of the brace where the sleeve has begun to dig into the side of the post. The penetration point being circled highlights this event.

Wood material #143 post.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the single flap method. The top half of the post leans at a rough twenty-five degree angle. The post has split just below the surface in which it is embedded, with only a fraction of the post remaining to hinge the upper and lower halves together. With the top half of the post leaning to the right, the sleeve has begun to dig into the side of the structure. The penetration point being circled highlights this event.

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Figure 117. The post breaks earlier in time when modeled with post-peak hardening (default saturated Grade 1 pine properties with Ghard equals 0.5). Diagrams.

The entry point in the following diagrams has been accentuated with a straight line being drawn over the top of the opening in which the post is embedded into the concrete brace.

5 milliseconds.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the double flap method. The sleeves can be seen on either side of the post, folded over at the entry point. The majority of the post is colored yellow with only a small section near the top colored red and representing the impact point and another small section colored red representing the breaking area. This latter area is the area in which the post is embedded into the concrete brace. The post has begun to split in the red “breaking area” as the post leans a slight degree to the right. The gap forming runs three-quarters the width of the post.

10 milliseconds.

This figure shows the post leaning further to the right. The gap forming has increased, the top half of the post now severed from the lower half in what appears to be a clean break.

25 milliseconds.

This figure shows the post now leaning at a rough twenty-five degree angle from its original position. The left-hand side corner of the break now rests just below the entry point of the concrete brace even with the accentuating straight line.

50 milliseconds.

This figure shows the post now leaning at a rough forty-five degree angle.  The top half of the post is shown to now be leaning completely out of the concrete brace and the sleeves, the break resting above the accentuating straight line.

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Figure 118. The post breaks by 15 milliseconds in this Douglas fir simulation (default saturated Grade 1 properties without rate effects). Diagrams.

5 milliseconds.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the double flap method.  The sleeves can be seen on either side of the post, folded over at the entry point.  The majority of the post is colored yellow with only a small section near the top colored red and representing the impact point and another small section colored red representing the breaking area.  This latter area is the area in which the post is embedded into the concrete brace.  No damage to the post is as of yet apparent.

10 milliseconds.

This figure shows the post leaning further to the right.  A gap has formed in the red “breaking area” section of the post, running nearly the entire width of the post.  The break, which has formed, is uneven in nature.

15 milliseconds.

This figure shows the post leaning to the right at a rough twenty-five degree angle.  The gap in the red “breaking area” has widened the top half of the post now appearing severed from the lower half of the post.  The break still remains uneven.

50 milliseconds.

This figure shows the top half of the post leaning at a rough fifty-degree angle, now completely severed from the lower half and existing well outside the original entry point.  Some minor damage appears to have occurred to the impact area as well, with a small dent in the post visible in this area.

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Figure 119. Bogie impact at 29.5 miles per second for a Grade 1 wood post modeled without rate effects (Grade 1 default saturated pine properties).

5 milliseconds.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the double flap method. The sleeves can be seen on either side of the post, folded over at the entry point. The majority of the post is colored yellow with only a small section near the top colored red and representing the impact point and another small section colored red representing the breaking area. This latter area is the area in which the post is embedded into the concrete brace. The post has begun to split in the red “breaking area” as the post leans a slight degree to the right. The gap forming runs only a quarter the width of the post.

10 milliseconds.

This figure shows the top half of the post leaning to the right hand side as a gap forms in the red section of the post from the resulting impact. The top half leans at a rough twenty-five degree angle from its original position. The gap itself runs nearly the width of the post, and a fracture has occurred at the impact area.

15 milliseconds.

This figure shows the post leaning to the right at a rough twenty-five degree angle. The gap in the red “breaking area” has widened the top half of the post now appearing severed from the lower half of the post. The break appears to be clean and even.

36 milliseconds.

This figure shows the top half of the post leaning at a rough fifty-degree angle, now completely severed from the lower half and existing well outside the original entry point.

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Figure 120. Bogie impact at 29.5 miles per seconds for a saturated Grade 1 wood post modeled with rate effects (default pine properties). Diagrams.

4 milliseconds.

This figure shows a computer-generated illustration of a post embedded in a concrete brace using the double flap method. The sleeves can be seen on either side of the post, folded over at the entry point. The majority of the post is colored yellow with only a small section near the top colored red and representing the impact point and another small section colored red representing the breaking area. This latter area is the area in which the post is embedded into the concrete brace. The post has begun to split in the red “breaking area” as the post leans a slight degree to the right. The gap forming runs only a quarter the width of the post.

10 milliseconds.

This figure shows the top half of the post leaning to the right hand side as a gap forms in the red section of the post from the resulting impact. The top half leans at a rough twenty-five degree angle from its original position. The gap itself runs nearly the width of the post, and a fracture has occurred at the impact area.

15 milliseconds.

This figure shows the post leaning to the right at a rough twenty-five degree angle. The gap in the red “breaking area” has widened the top half of the post now appearing nearly severed from the lower half of the post. The break appears to be clean and even.

34 milliseconds.

This figure shows the top half of the post leaning at a rough ninety-five degree angle, now completely severed from the lower half and existing well outside the original entry point. The breaking area appears mangled and jagged, the break itself uneven and distorted.

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Figure 121. Fringes of damage for bogie impact at 29.5 miles per second (default properties for saturated Grade 1 pine with rate effects). Diagrams.

The four diagrams are accompanied by a legend to the right hand side of the figure. The legend shows indicated fringe levels, in a variety of colors. The scale begins in dark blue, being the lowest fringe level, scales up through green, then yellow and into red, representing the highest fringe level.

4 milliseconds.

This figure shows a computer-generated illustration of a post. The top half of the post leans to the right at a slight degree with a gap forming near the mid-point of the structure. The majority of the post is colored a dark blue. The small section of yellowish-green is visible just under the gap as is there another section of the same color near the top of the top half of the post near the impact area.

10 milliseconds.

This figure shows a computer-generated illustration of a post. The top half of the post leans considerably more to the right, at a rough twenty-five degree angle from its original position. The gap forming at the mid-point of the structure has widened. The section beneath the gap colored green has increased in length.

15 milliseconds.

This figure shows a computer-generated illustration of a post. The top half of the post leans further still to the right at a rough forty-five degree angle. The small section of green beneath the gap remains the same as does the section at the top of the top half of the post, though the small section of the post now holding the two halves together appears to be colored a light green.

34 milliseconds.

This figure shows a computer-generated illustration of a post. The top half of the post now rests at a rough ninety-degree angles with the lower half. The gap now appears mangled and jagged with the area just above it colored light green to dark red. All other fringe levels remain the same.

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Figure 122. Unstable behavior in the developers rigid sleeve calculation. Diagrams.

Model.

This figure shows a computer-generated illustration of a post embedded into the sleeve outlining the concrete brace. This image clearly shows the post in red, with the sleeves on either side of the post running half the length of the structure and colored a dark gray.

0.002 milliseconds.

This figure shows a computer-generated illustration of a post. The sleeves on either side of the post have been removed. A small rectangular section is shown missing from the bottom left-hand side of the post.

0.0065 milliseconds.

This figure shows a computer-generated illustration of a post. The sleeves on either side of the post have been removed. The small rectangular section missing from the bottom left-hand has grown into a small arc of missing from that area.

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Figure 123. Unstable behavior in the user’s rigid sleeve calculation. Diagrams.

The first image in this figure shows a computer-generated illustration of a post. The post is colored a dark red and the front end of the impact vehicle is illustrated near the top left-hand side of the structure. The entire post remains in tact in this first image.

The second image in this figure shows a computer-generated illustration of a post. The post appears to be bent ever so slightly from the mid-point of the structure and arcing outward both to the upper and lower halves. The bottom left-hand side of the post also appears to have deteriorated slightly.

The third image in this figure shows a computer-generated illustration of a post. The top half of the post now leans slightly to the right as a gap has begun to form near the mid-point of the structure. The deterioration at the bottom left-hand side of the post has increased in both width and length, now running nearly half the length of the lower half of the structure.

The fourth and final image in this figure shows a computer-generated illustration of a post. The top half of the post leans considerably more to the right and the gap at the mid-point of the structure has widened. The gap itself appears to be a clean and even break. The deterioration near the bottom left-hand side of the post has increased, again both in width and length, now extending around either side of the post and up to the mouth of the gap itself.

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Figure 124. LS-DYNA diagnostics indicate that a contact surface is improperly positioned and requires movement of nodes prior to running the simulation.

This figure is a screen capture of a printout of LS-DYNA diagnostics. The screen indicates a warning of initial penetration through contact surface, and provides data regarding the interface number, type, moved node, closest node, segment, penetration, normal, and node.

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Figure 125. The liner does not penetrate the post in calculations conducted with LS-DYNA version 960. Diagrams.

25 milliseconds.

This figure shows a close-up of a computer-generated illustration of a post near the breaking area. The illustration shows the post colored blue, the liner sleeve on the left-hand side colored dark purple and the liner sleeve on the right hand side colored pink. The sleeve on the left-hand side is shown folded over slightly in the single flap fashion while the opposite side is shown severed near the entry point. The top half of the post leans roughly twenty-five degrees to the right, causing a large gap to form at the mid-point of the structure and the right hand sleeve to push away ever so slightly from the side of the post.

38 milliseconds.

This figure shows a close-up of a computer-generated illustration of a post near the breaking area. The illustration shows the post colored blue, the liner sleeve on the left-hand side colored dark purple and the liner sleeve on the right hand side colored pink. The sleeve on the left-hand side is shown folded over slightly in the single flap fashion while the opposite side is shown severed near the entry point. The top half of the post leans a few degrees further to the right, causing a larger gap to form at the mid-point of the structure and the right hand sleeve to push away a touch further from the side of the post.

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United States Department of Transportation - Federal Highway Administration