U.S. Department of Transportation
Federal Highway Administration
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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
| REPORT |
| This report is an archived publication and may contain dated technical, contact, and link information |
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| Publication Number: FHWA-HRT-16-010 Date: March 2017 |
Publication Number: FHWA-HRT-16-010 Date: March 2017 |
This screen capture shows the summary of condition inputs for level 1. Shown is the “Structure” screen with the “Rut” column and “Rehabilitation Level” circled. (1 inch = 25.4 mm.)
This screen capture shows the summary of condition inputs for level 3. Shown is the “Structure” screen with “Rehabilitation Level,” “Pavement Rating,” and “Total Rutting” circled. (1 inch = 25.4 mm.)
This graph summarizes Long-Term Pavement Performance Program laboratory-measured subgrade resilient moduli. The x-axis is bulk stress, with a range of 0 to 30 psi. The y-axis is resilient modulus, with a range of 0 to 10,000 psi. Material BS05 consistently measures a high resilient modulus in comparison with other materials, while material BS07 consistently measures a low resilient modulus in comparison with other materials. The measured resilient moduli of the other six materials-BS02, BS03, BS08, BS09, BS11, and BS12-fall between those of material BS05 and BS07. (1 psi = 6.89 kPa.)
This graph summarizes the Long-Term Pavement Performance Program laboratory-measured base aggregate resilient moduli. The x-axis is bulk stress, with a range of 0 to 120 psi. The y-axis is resilient modulus, with a range of 0 to 35,000 psi. Three materials are measured-BG13, BG14, and BG15. At 10-psi bulk stress, BG13 begins with a resilient modulus of 10,000 psi and continues to rise steadily to 44,000 psi at a bulk stress of 100 psi. For the same bulk stress range, BG14 begins with a resilient modulus of 7,500 psi and rises steadily to 42,000 psi. BG15 falls in between. (1 psi = 6.89 kPa.)
This graph summarizes the Long-Term Pavement Performance (LTPP) Program laboratory-measured average hot mix asphalt (HMA) resilient modulus for six HMA samples from the LTPP project section test 30-0100, I-15 near Great Falls, MT (case study 1). The x-axis is the test temperature from 0 to 120 °F. The y-axis is resilient modulus from 0 to 2 million psi. The instantaneous resilient modulus ranges from 1,200,000 to 1,750,000 psi at 40 °F, from 200,000 to 400,000 psi at 77 °F, and from 25,000 to 90,000 psi at 104 °F. The total resilient modulus ranges from 1,100,000 to 1,625,000 psi at 40 °F, from 190,000 to 340, psi at 77 °F, and from 25,000 to 80,000 psi at 104 °F.(1 psi = 6.89 kPa. °F = 1.8×°C +32.)
This figure shows sample plots of load versus sensor deflection for various falling weight deflectometer test locations taken in 1999 and 2005. Each graph has an x-axis with deflection (mils) from 0 to 35 and a y-axis with load (lb) from 0 to 18,000. The 1999 plots show greater deflection increases with heavier test load, indicating very slight stress softening. The 2005 plots show a slight stress hardening, with deflection increases beginning to lessen with heavier test load. (1 lb = 0.454 kg. 1 mil = 0.0254 mm.)
This figure shows the backcalculated layer moduli (using the MODTAG backcalculation program) for four different layer combinations. The x-axis is the station from 0 to 600 ft, and the y-axis is the modulus from 1,000 to 1 million psi. The four combinations are the following: (a) three-layer system with infinite subgrade, (b) four-layer system with infinite subgrade, (c) three-layer system with rigid layer, and (d) four-layer system with rigid layer. The three-layer systems both include a hot-mix asphalt (HMA) layer, base layer, and subgrade. The four-layer system adds a 2-ft compacted subgrade on top of an infinite subgrade. For each combination, the HMA layer falls between 500,000 and 1 million psi modulus, whereas the other layers fall between 7,000 and 50,000 psi modulus. (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This graph shows root mean square (RMS) values (using the MODTAG backcalculation program) for four different layer combinations. The x-axis is station from 0 to 600 ft, and the y-axis is RMS from 0 to 20 percent. The four combinations shown are three-layer with bedrock, four-layer with bedrock, three-layer with infinite subgrade, and four-layer with infinite subgrade. Three-layer with infinite subgrade typically scores a higher RMS percent than the others, while four-layer with infinite subgrade typically scores a lower RMS percent than the others. (1 ft = 0.305 m.)
This figure shows the backcalculated layer moduli. The x-axis shows station from 0 to 600 ft, and the corresponding y-axis is modulus from 1,000 to 1 million psi. The moduli for the hot mix asphalt (HMA) layer, base layer, and subgrade layer are shown, with the HMA layer modulus ranging between 500,000 and 1 million psi, the base layer modulus ranging between 8,000 and 30,000 psi, and the subgrade modulus about 40,000 psi. (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This figure shows the root mean square (RMS) values from the EVERCALC© backcalculation program. The x-axis shows station from 0 to 600 ft, and the corresponding y-axis is RMS from 0 to 5 percent. The RMS data points generally fall below 3 percent, with the exception of one value of 4.5 percent occurring at the station at 500 ft. (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This figure shows backcalculated layer moduli. The x‑axis is station from 0 to 600 ft. The y-axis is modulus from 1,000 to 1 million psi. The moduli for the hot mix asphalt (HMA) layer, base layer, and subgrade layer are shown, with HMA layer ranging from 500,000 to 1 million psi, the at about 40,000 psi, and the base between 8,000 and 30,000 psi. (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This figure shows root mean square (RMS) values from the MICHBACK© backcalculation program. The x-axis is station from 0 to 600 ft. The y-axis is RMS from 0 to 5 percent. The data generally fall below 3 percent with the exception of one spike at 4.5 percent at the station at 500 ft. (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This figure shows three bar graphs summarizing backcalculated results for a three-layer system comparing the backcalculation results from the MODTAG, MICHBACK©, and EVERCALC© programs. The x-axis for all three graphs has stations from 0 to 500 ft. The top bar graph shows asphalt concrete (AC) modulus versus location, with the y-axis with 1,200,000 psi AC modulus. The results for MICHBACK© and EVERCALC© are very comparable throughout the graph, with both starting just above 600,000 psi until 300 to 500 ft, where they drop below 600,000 psi. MODTAG begins at almost 1 million psi at station 0 and then drops to near the other two until it spikes again to 900,000 psi at 150 ft. The middle bar graph shows base modulus versus location, with a y-axis of 0 to 25,000 psi base modulus. Again, MICHBACK© AND EVERCALC© are comparable. MODTAG starts low at 7,000 psi, but then has consistently higher moduli from station 50 on. The bottom bar graph shows subgrade modulus versus location, with a y-axis of 0 to 40,000 psi subgrade modulus. Again, MICHBACK© AND EVERCALC© are comparable. MODTAG starts high at 34,000 psi but then drops below the other two to consistently show a lower modulus. (1 psi = 6.89 kPa.)
This figure summarizes backcalculated results (using MODTAG and EVERCALC©) for a four-layer system. It is subdivided into four bar graphs, each having an x-axis that shows test location from 0 to 500 ft. The top left bar graph shows asphalt concrete (AC) modulus versus location, with AC modulus given on the y-axis and ranging from 0 to 1,200,000 psi. MODTAG values range from 40,000 to 1 million psi, depending on location. EVERCALC© values range from 60,000 to 1 million psi, depending on location. The top right bar graph shows base modulus versus location, with a y axis of 0 to 25,000 psi base modulus. MODTAG values start low at 6,000 psi at station 0 but then increase to higher and more consistent modulus values (14,000 to 23,000 psi) than EVERCALC© values. The bottom left bar graph shows the top 2 ft of subgrade modulus versus location, with a y-axis of 0 to 200,000 psi modulus. The MODTAG values start high at 175,000 psi at station 0 but then drop to under 20,000 psi for the remaining locations. The EVERCALC© values are about 20,000 psi for most locations, except station 450, where it increases to 40,000 psi. The bottom right graph shows the infinite subgrade modulus versus location, with a y-axis of 0 to 30,000 psi. Most bars are between 27,000 and 32,000 psi for both MODTAG and EVERCALC©. EVERCALC© has a consistently higher modulus. ((1 psi = 6.89 kPa.)
M subscript R equals the product of k subscript 1 times p subscript a times the quotient of lowercase theta divided by p subscript a, end quotient to the power k subscript 2, times the quantity quotient of lowercase tau divided by p subscript a, end quotient, plus 1, end quantity to the k subscript 3 power, end product.
This graph shows the estimated constitutive model for subgrade resilient modulus. The x-axis is bulk stress from 0 to 30 psi, and the y-axis is resilient modulus from 0 to 12,000 psi. The combinations shown are BS02, BS03, BS05, BS07, BS08, BS09, BS11, BS12, and the constitutive model. BS05 typically has the highest resilient modulus, while BS07 typically has a lower resilient modulus than the others. (1 psi = 6.89 kPa.)
This graph shows the estimated constitutive model for base resilient modulus. The x-axis is bulk stress from 0 to 120 psi, and the y-axis is resilient modulus from 0 to 50,000 psi. The combinations shown are BG13, BG14, BG15, and the constitutive model. BG13 typically has the highest resilient modulus, while BG14 typically has the lowest resilient modulus. (1 psi = 6.89 kPa.)
This graph shows the approximate hot mix asphalt resilient modulus based on Long-Term Pavement Performance Program laboratory testing. The x-axis shows temperature from 0 to 120 °F. The y-axis shows resilient modulus from 0 to 2 million psi. Combinations shown are 1,200,000 to 1,750,000 psi at 40 °F, 200,000 to 400,000 psi at 77 °F, and 50,000 to 100,000 psi at 104 °F. (1 psi = 6.89 kPa. °F = 1.8 × °C +32.)
This graph illustrates the hot mix asphalt dynamic modulus master curve based on the Mechanistic-Empirical Pavement Design Guide design software. The x-axis shows the log of the reduced time from -6 to 6. The y-axis shows E* from 0 to 2,500,000. The curve begins at E*equals2,300,000 at -5, then drops steadily to 600,000 at -1 where it begins to even out ending at just above E*equals0 at 5.
This screen capture shows the “Asphalt Material Properties” at layer input level 3. “Modulus,” “Frequency,” and “Temperature” inputs are circled. (1 inch =25.4 mm.)
This screen capture shows the “Unbound Layer” at layer input level 1. “NDT Test-Modulus” and “Correction factor” are circled. (1 psi = 6.89 kPa. 1 inch = 25.4 mm.)
This graph shows top-down cracking distress prediction from the Mechanistic-Empirical Pavement Design Guide design program for analysis 3. The x-axis is pavement age from 0 to 264 mo. The y-axis is longitudinal cracking from 0 to 3,000 ft/mi. Charted are the surface, depth, surface at reliability, and design limit. The depth (0.5 inches) remains near 0 cracking for 240 mo. The surface remains under 50 ft/mi cracking for the entire 240 mo. The surface at the selected reliability begins at 300 ft/mi longitudinal cracking, and increases about 150 ft/mi for each 12-month period until it reaches a value of about 1,950 ft/mi at 240 mo. The design limit is set at 2,000 ft/mi. (1ft/mi = 0.19 m/km.)
This graph summarizes the Long-Term Pavement Performance Program laboratory-measured subgrade resilient moduli for test sample BAX04. The x-axis is bulk stress from 0 to 17 psi. The y-axis is the average subgrade resilient modulus from 0 to 18,000 psi. At bulk stress 5 psi, there is a mark at 12,000 psi average subgrade resilient modulus. At bulk stress 6 psi, there are marks at 12,000 and 15,000 psi. At bulk stress 8 psi, there are marks at 11,900, 14,500, and 16,000 psi. At bulk stress 10 psi, there are marks at 11,800, 14,000, and 16,000 psi. At bulk stress 12 psi, there are marks at 11,800, 13,500, and 15,500 psi. At bulk stress 14 psi, there are marks at 13,000 and 15,000 psi. At bulk stress 16 psi, there is a mark at 14,200 psi. (1 psi = 6.89 kPa.)
This graph summarizes the Long-Term Pavement Performance Program laboratory-measured base aggregate resilient moduli for test samples BAX02 and BGX03. The x-axis is bulk stress from 0 to 44 psi. The y-axis is the average base resilient modulus from 0 to 60,000 psi. At bulk stress 6 psi, there is a BAX02 mark at 15,000 psi average base resilient modulus and a BGX03 mark at 13,000 psi average base resilient modulus. At bulk stress 9 psi, there is a BAX02 mark at 16,000 psi and a BGX03 mark at 14,000 psi. At bulk stress 10 psi, there is a BAX02 mark at 18,000 psi and a BGX03 mark at 16,000 psi. At bulk stress 12 psi, there is a BAX02 mark at 17,000 psi and a BGX03 mark at 14,000 psi. At bulk stress 15 psi, there is a BAX02 mark at 20,000 psi and a BGX03 mark at 19,000 psi. At bulk stress 20 psi, there is a BAX02 mark at 21,000 psi and a BGX03 mark at 20,000 psi. Just above bulk stress 20 psi, both marks are at 27,000 psi. At bulk stress 25 psi, there is a BAX02 mark at 32,000 psi and a BGX03 mark at 35,000 psi. At bulk stress 30 psi, there is a BAX02 mark at 30,000 psi nd BGX03 mark at 30,500 psi. At just above bulk stress 30 psi, there is a BAX02 mark at 34,000 psi and a BGX03 mark at 36,000 psi. At bulk stress 36 psi, there is a BAX02 mark at 40,000 psi and a BGX03 mark at 44,000 psi. At bulk stress 40 psi, there is a BAX02 mark at 32,000 psi and a BGX03 mark at 34,000 psi. At bulk stress 41 psi, there is a BAX02 mark at 42,000 psi and a BGX03 mark at 47,000 psi. (1 psi = 6.89 kPa.)
This graph summarizes the Long-Term Pavement Performance Program laboratory-measured compressive strength. The x-axis is 0 to 200,000 lb maximum applied load to specimen. The y-axis is 0 to 7,000 psi compressive strength of core. When the maximum applied load to specimen is between 50,000 and 70,000 lb, the compressive strength of core is between 4,000 and 5,500 psi. When maximum applied load to specimen is between 150,000 and 180,000 lb, the compressive strength of core is between 5,400 and 6,500 psi. (1 psi = 6.89 kPa. 1 lb = 0.454 kg.)
This graph summarizes the hot mix asphalt resilient modulus data as a function of temperature from the Long-Term Pavement Performance Program. The vertical axis shows resilient modulus values ranging from 0 to 2,500,000 psi, while the x-axis shows temperature values ranging 20 to 120 °F. Four different resilient modulus values are shown (Surface-Instant, Surface-Total, Binder-Instant, and Binder-Total), the values of which decrease with increasing temperature. Each begins in the upper left-hand corner of the chart at nominal values of between 2 million and 2,400,000 psi for a temperature of 40 °F and decreases to nominal values of about 300,000 psi for a temperature of 105 °F. The chart also shows how standard modulus values can be selected for a standard temperature of 70 °F. (1 psi = 6.89 kPa. °F = 1.8 × °C +32.)
This figure compares sample plots of falling weight deflectometer (FWD) load versus sensor deflection before and after rubblization. The top graph depicts the results prior to rubblization. The x-axis shows a load range of 8,000 to 18,000 lb. The y-axis shows deflection from 0 to 8 mils. The results for seven FWD sensors are shown. The graph shows that before rubblization, the measured deflections are somewhat lower and less variable. The bottom graph depicts results after rubblization. The x-axis shows a load range of 4,000 to 18,000 lb. The y-axis shows deflection from 0 to 9 mils. Results for seven FWD sensors are shown. This graph shows that after rubblization, the measured deflections are somewhat higher and more variable. (1 lb = 0.454 kg. 1 mil = 0.0254 mm.)
This figure shows two sample plots of typical deflection basins prior to and after rubblization. Both graphs have an x-axis of sensor locations from 0 to 70 inches. The y-axis on the top graph (prior to rubblization) shows deflection from 0 to 8 mils, while the y-axis on graph (b) (after rubblization) shows deflection from 0 to 9 mils. The “after rubblization” graph is more irregular owing to the variability of the rubblized material. (1 mil = 0.0254 mm. 1 inch = 25.4 mm.)
This graph shows normalized deflections along the section. The x-axis shows the station from 0 to 600 ft. The y-axis shows the 9,000-lb normalized deflection in mils. Marks are for Pre-rubblization and Post-overlay. Pre-rubblization marks fall at about 4 mils, while post-overlay marks fall between 5 and 7 mils. (1 mil = 0.0254 mm. 1 ft = 0.305 m)
This figure shows four graphs portraying backcalculation results for four-layer systems with a separate rubblized layer. The four layers evaluated include asphalt concrete surface, rubblized portland cement concrete base, aggregate base, and subgrade. The two graphs on the top show the backcalculated moduli (psi) for each layer and root mean square (RMS) values (percent), respectively, at different falling weight deflectometer (FWD) test locations using the MICHBACK© program. The two graphs at the bottom show the backcalculated moduli (psi) for each layer and RMS values (percent), respectively, at different FWD test locations using the EVERCALC© program. In each graph, the x-axis is the FWD test location (by station). The y-axis range for backcalculated moduli is 1,000 to 1 million psi. The y-axis range for MICHBACK© RMS is 0 to 25 percent, whereas for EVERCALC© RMS, the y-axis range is 0 to 5 percent. The figure shows very high variability, especially in the modulus of the rubblized and base layers. It also shows that the MICHBACK© RMS values were much higher that the EVERCALC© RMS values. (1 psi = 6.89 kPa.)
This figure shows six graphs portraying backcalculation results for four-layer systems with a combined base and rubblized layer. The four layers evaluated include asphalt concrete surface, combined rubblized portland cement concrete base and aggregate base, top 2 ft of compacted subgrade, and infinite subgrade. The top left and right graphs show the backcalculated moduli (psi) for each layer and root mean square (RMS) values (percent), respectively, at different falling weight deflectometer (FWD) test locations using the MICHBACK© program. The middle left and right graphs show the backcalculated moduli (psi) for each layer and RMS values (percent), respectively, at different FWD test locations using the EVERCALC© program. The bottom left and right graphs show the backcalculated moduli (psi) for each layer and RMS values (percent), respectively, at different FWD test locations using the MODCOMP© program. In each graph, the x-axis is the FWD test location (by station). The y-axis range for backcalculated moduli is 1,000 to 1 million psi. The y-axis range for MICHBACK© RMS is 0 to 25 percent, whereas for EVERCALC© RMS and MODCOMP© RMS, the y-axis range is 0 to 5 percent. The figure shows very high variability, especially in the modulus of the top 2 ft of compacted subgrade. The MICHBACK© RMS values were the highest, while the EVERCALC© RMS values were the lowest. (1 psi = 6.89 kPa.)
This figure shows a graph with backcalculation results for three-layer systems with a combined base and rubblized layer. The three layers evaluated include asphalt concrete surface, combined rubblized portland cement concrete base and aggregate base, and subgrade. The graph shows the backcalculated moduli (psi) for each layer at different FWD test locations using the EVERCALC© program. The x-axis is the FWD test location (by station). The y-axis range is 1,000 to 1 million psi. The figure shows that the results are less variable than those involving a four-layer analysis. The most variable layer is the combined rubblized and base layer. (1 psi = 6.89 kPa.)
This figure shows a graph with backcalculation results for three-layer systems with a combined base and rubblized layer. The three layers evaluated include asphalt concrete surface, combined rubblized portland cement concrete base and aggregate base, and subgrade. The graphs shows the root mean square (RMS) values (percent) at different FWD test locations using the EVERCALC© program. The x-axis is the FWD test location (by station). The y-axis ranges for RMS is 0 to 5 percent. Most RMS values are below 2 percent.
This bar graph summarizes the average backcalculated moduli for a four-layer system with a separate rubblized layer. The four layers evaluated and displayed along the x-axis include hot mix asphalt (HMA), rubblized portland cement concrete (PCC) base, aggregate base, and subgrade. The y-axis is backcalculated modulus on a scale of 1,000 to 1million psi. The MICHBACK© HMA modulus is similar to EVERCALC© (approximately 3 million psi). The rubblized PCC moduli are identical at just over 100,000 psi. The EVERCALC© base modulus is slightly higher than the MICHBACK© base modulus (30,000 versus 25,000 psi). The MICHBACK© subgrade modulus is considerably higher than the EVERCALC© modulus (40,000 versus 20,000 psi). This figure and figure 35 and figure 36 are shown to convey that the different programs give generally comparable backcalculated modulus values. (1 psi = 6.89 kPa.)
This bar graph summarizes the average backcalculated moduli for a four-layer system with a combined base and rubblized layer. The four layers evaluated and displayed along the x-axis include hot mix asphalt (HMA), combined rubblized portland cement concrete (RPCC) base and aggregate base, top 2 ft of compacted subgrade, and infinite subgrade. The y-axis is backcalculated modulus on a scale of 1,000 to 1 million psi. The MICHBACK©, EVERCALC©, and MODCOMP5 HMA moduli are identical at about 3 million psi. The combined RPCC and aggregate base moduli are similar at just under 100,000 psi. The top 2 ft of subgrade moduli are similar at about 30,000 psi. The subgrade moduli are identical between MICHBACK© and EVERCALC©, with MODCOMP5 only slightly higher at about 50,000 psi. Again, this figure, figure 34, and figure 36 are shown to convey that the different programs give comparable backcalculated modulus values. (1 psi = 6.89 kPa.)
This bar graph summarizes the average backcalculated moduli for a three-layer system with a combined base and rubblized layer. The three layers evaluated and displayed along the x-axis include hot mix asphalt (HMA), combined rubblized portland cement concrete (RPCC) base and aggregate base, and subgrade. The y-axis is backcalculated modulus on a scale of 1,000 to 1 million psi. The EVERCALC© HMA modulus is at about 3 million psi, the combined RPCC and aggregate base modulus is at about 75,000 psi, and the subgrade modulus is at about 40,000 1 psi. Again, this figure and figure 34 and figure 35 are shown to convey that the different programs give comparable backcalculated modulus values. (1 psi = 6.89 kPa.)
This screen capture shows the rubblized portland cement concrete input screen. It displays “JPCP (existing) Material.” (1 inch = 25.4 mm. 1 pcf = 16 kg/m3. 1 psi = 6.89 kPa. 1 BTU/hr-ft-°F = 1.73 W/m-°C 1. BTU/lb-°F = 4,186.8 J/kg-°C.)
This screen capture shows the unbound layer input screen for hot mix asphalt over jointed Portland cement concrete pavement (fractured) design. It shows “Unbound Layer-Layer #5.”
This graph summarizes the required overlay thickness based on surface rutting for analysis 1. The x-axis shows hot mix asphalt (HMA) overlay thickness ranging from 5 to 8 inches. The vertical axis shows predicted reliability from 0 to 100 percent. When HMA overlay thickness is 6 inches, the predicted reliability is 79 percent; when thickness is 6.5 inches, reliability is 89 percent; and when thickness is 7 inches, the reliability is 96 percent. (1 inch = 25.4 mm.)
This graph shows slab temperatures for the falling weight deflectometer tests performed on Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV (case study 3) on 03/26/1996. The x-axis is temperature from 40 to 90°F. The y-axis is slab depth from 0 to 12 inches. Temperature profiles at different times of the day are shown. The figure shows that slab temperatures increase throughout the day and that they are season and time dependent. The average slab temperature is 58 °F. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer tests performed on Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV (case study 3) on 6/15/2000. The x-axis is temperature from 70 to 120 °F. The y-axis is slab depth from 0 to 12 inches. Temperature profiles at different times of the day are shown. The figure shows that slab temperatures increase throughout the day and that they are season and time dependent. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer tests performed on Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV (case study 3) on 6/24/2002. The x-axis is temperature from 70 to 120 °F. The y-axis is slab depth from 0 to 12 inches. Temperature profiles at different times of the day are shown. The figure shows that slab temperatures increase throughout the day and that they are season and time dependent. The average temperature is 96 °F. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer tests performed on Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV (case study 3) on 10/28/2003. The x-axis is temperature from 50 to 100 °F. The y-axis is slab depth from 0 to 12 inches. Temperature profiles at different times of the day are shown. The figure shows that slab temperatures increase throughout the day and that they are season and time dependent. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows Long-Term Pavement Performance Program data of laboratory resilient modulus testing on five subgrade samples, designated BS03, BS04, BS05, BS06, and BS07. The x-axis is bulk stress from 0 to 30 psi. The y-axis is resilient modulus from 0 to 16,000 psi. The graph generally shows resilient modulus decreases as the bulk stress is increases. For instance, in one scenario, sample BS03 decreases from 12,400 psi at 20 psi bulk stress to 9,900 psi at 28 psi bulk stress. (1 psi = 6.89 kPa.)
This graph shows the gradation of seven subgrade samples, designated BS01, BS02, BS03, BS04, BS05, BS06, and BS07. The x-axis is particle size on a log scale from .001 to 10 inches. The y-axis is the percentage finer by weight from 0 to 100 percent. The gradation curves for each sample are displayed. The coarsest sample is BS02, which has 44 percent of its particles (by weight) smaller than 0.01 inches and 85 percent of its particles (by weight) smaller than 0.1 inches. The finest sample is BS06, which has 89 percent of its particles (by weight) smaller than 0.01 inches and 99 percent of its particles (by weight) smaller than 0.1 inches. (1 inch = 25.4 mm.)
This graph shows the gradation of subbase samples, designated BG01, BG02, BG03, BG04, BG05, BG06, and BG07. The x-axis is particle size on a log scale from .001 to 10 inches. The y-axis is the percentage finer by weight from 0 to 100 percent. The gradation curves for each sample are displayed. One of the coarsest samples is BG05, which has 19 percent of its particles (by weight) smaller than 0.01 in and 40 percent of its particles (by weight) smaller than 0.1 inches. One of the finest samples is BG07, which has 31 percent of its particles (by weight) smaller than 0.01 inches and 56 percent of its particles (by weight) smaller than 0.1 inches. (1 inch = 25.4 mm.)
This graph shows the gradation of base samples, designated BG21, BG22, BG23, BG24. The x-axis is particle size from .001 to 10 inches. The y-axis is the percentage finer by weight from 0 to 100 percent. The gradation curves for each sample are displayed. One of the coarsest samples is BG23, which has 14 percent of its particles (by weight) smaller than 0.01 inches, 30 percent of its particles (by weight) smaller than 0.1 inches, and 95 percent of its particles (by weight) smaller than 1 inch. The finest sample is BG21, which has 21 percent of its particles (by weight) smaller than 0.01 inches, 48 percent of its particles (by weight) smaller than 0.1 inches, and 99 percent of its particles (by weight) smaller than 1 inch. (1 inch = 25.4 mm.)
This graph shows Long-Term Pavement Performance Program data of laboratory resilient modulus testing on three base samples, designated BG21, BG22, and BG24. The x-axis is bulk stress from 0 to 120 psi. The y-axis is resilient modulus from 0 to 45,000 psi. Each sample shows that the resilient modulus increases somewhat linearly as the bulk stress increases. The weakest sample, BG22, increases from 10,500 psi at 16 pounds psi bulk stress to 35,500 psi at 104 psi bulk stress. The strongest sample, BG21, increases from 13,500 psi at 16 psi bulk stress to 42,500 psi at 104 psi bulk stress. (1 psi = 6.89 kPa.)
This graph shows regression analysis for the estimated traffic growth rate for case study 3 (Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV). The x-axis is service life from 0 to 18 years. The y-axis is average annual daily traffic (AADT) from 5,000 to 9,000 vehicles per day (vpd). The figure shows that the AADT steadily increases (with some variance among the years) from 5,000 vpd at 0 years to 7,800 vpd at 17 years.
This graph shows the original deflection basins for multiple falling weight deflectometer test locations for case study 3 (Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV). The x-axis is drop distance from -20 to 80 inches. The y-axis is deflection from 0 to 5.5 mils. This figure shows that there is an irregular relationship between load positions and deflections. Figure 51 shows the adjustments made as a result of these irregular relationships. (1 mil = 0.0254 mm. 1 inch = 25.4 mm.)
This graph shows how the outlier data points in figure 50 were realigned by adjusting their position to obtain a smooth deflection basin. The x-axis is drop distance from -20 to 80 inches. The y-axis is deflection from 0 to 3.5 mils. This figure shows that there is a regular relationship between load positions and deflections. (1 mil = 0.0254 mm. 1 inch = 25.4 mm.)
This graph shows the normalized maximum deflections along Long-Term Pavement Performance Program test section 32-0203. The x-axis is distance along the section from 0 to 500 ft. The y-axis is normalized maximum deflection from 0 to 4 mils. Data points shown are (25, 2.9), (50, 2.6), (150, 2.6), (200, 2.45), and (250, 2.48). (1 ft = 0.305 m. 1 mil = 0.0254 mm.)
This graph shows the dynamic k-values along the section. The x-axis is distance along the section from 0 to 500 ft. The y-axis is dynamic k-value from 0 to 600 psi/inch. Data points shown are (25, 275), (50, 290), (150, 420), (200, 400), and (250, 490). (1 ft = 0.305 m. 1 psi/inch = 0.263 kPa/mm.)
This graph shows radius of relative stiffness along Long-Term Pavement Performance Program test section 32-0203. The x-axis is distance along the section from 0 to 500 ft. The y-axis is radius of relative stiffness from 0 to 45 inches. Data points shown are (25, 37), (50, 37), (150, 31), (200, 33), and (250, 30). (1 inch = 25.4 mm. 1 ft = 0.305 m.)
This graph shows portland cement concrete elastic modulus along the section. The x-axis is distance along the section from 0 to 500 ft. The y-axis is dynamic elastic modulus from 0 to 6,000,000 psi. Data points shown are (25, 4,900,000), (50, 4,700,000), (150, 3,100,000), (200, 3,800,000), and (250, 2,800,000). (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This graph shows load transfer efficiency (LTE) values from 1996 to 2003 for case study 3 (Long-Term Pavement Performance Program test section 32-0203 on I-80 in Lander County, NV). The x-axis is distance along the section from 0 to 500 ft. The y-axis is LTE from 70 to 110 percent. The LTE range is different for each test owing to the slab temperatures. At warmer temperatures (6/15/2000 and 6/25/2002), the slabs expand, causing the joints to lock up and thus have a higher LTE. Testing at periods of lower temperature (3/26/1996 and 10/28/2003) results in a lower LTE. Data points show the trend of the variations in the LTE is maintained for all test periods. This indicates that the performance level of the joints along the section remains relatively constant over time. (1 ft = 0.305 m.)
This graph shows Y-intercepts from void detection test results. The x-axis is distance along the section from 0 to 500 ft. The y-axis is relative size of voids from -1 to 3 mils. The 3/26/1996, 6/15/2000, and 6/25/2002 test dates show the relative size of voids as negative. The 10/28/2003 test date shows the relative void sizes as ranging from 0 to 1.3 mils. The difference between the 2002 and 2003 data points indicates a possible loss of support, yet the data points are still smaller than 0.001 inches, suggesting that existing voids at this time are not probable. (1 mil = 0.0254 mm. 1 ft = 0.305 m.)
M subscript R equals 26 times k-value, to the 1.284 power.
This screen capture shows a screenshot of an unbound layer input screen illustrating Integrated Climatic Model selection. Shown is the “Unbound Layer-Layer #4” screen. (1 inch = 25.4 mm. 1 psi = 6.89 kPa.)
This screen capture shows an existing portland cement concrete (PCC) layer input screen for unbonded PCC overlay. Shown is the “JPCP (existing) Material” screen. 1 inch = 25.4 mm. 1 pcf = 16 kg/m3. 1 psi = 6.89 kPa. 1 BTU/hr-ft-°F = 1.73 W/m-°C 1. BTU/lb-°F =4,186.8 J/kg-°C)
This screen capture shows the dynamic k-value input for overlay design options. Shown is the “Rehabilitation” screen. (1 inch = 25.4 mm. 1 psi = 6.89 kPa.)
This graph shows slab temperatures for the falling weight deflectometer test performed for case study 4 (Long-Term Pavement Performance Program test section 05-0218 on I-30 in Saline County, AR) on 11/14/1996. The x-axis is temperature from 35 to 70 °F. The y-axis is depth from surface ranging from 0 to 8 inches. Temperatures were taken at various intervals throughout this cloudy day. The temperature profiles in this figure show that slab temperature increases only a few degrees throughout the day (from 47 to 49 °F to 54 to 55 °F) and that, in most cases, the surface of the slab is slightly cooler than the lower parts of the slab. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer test performed on 4/19/1999. The x-axis is temperature from 50 to 85 °F. The y-axis is depth from surface ranging from 0 to 8 inches. Temperatures were taken at various intervals throughout the morning (9 a.m. to 11 a.m.) on this sunny day. The figure shows that the slab warms throughout the morning owing to solar radiation, with the surface of the slab heating faster (from 60 to 77 °F) than the lower parts of the slab (from 59 to 66 °F). (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer test performed on 4/15/1999. The x-axis is temperature from 50 to 85 °F. The y-axis is depth from surface ranging from 0 to 8 inches. Temperatures were taken at various intervals throughout the afternoon (3 p.m. to 4:30 p.m.) on this cloudy day. The graph shows that both the surface of the slab and the lower parts of the slab warm minimally (1 to 2 °F) throughout the afternoon; the surface from 72 to 74°F, and the bottom from 67 to 68 °F. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer test performed on 7/26/2001. The x-axis is temperature from 90 to 125 °F. The y-axis is depth from surface ranging from 0 to 8 inches. Temperatures were taken at various intervals throughout this sunny day. The temperature profiles in this graph show that slab temperature increases substantially at the surface (from 91 to 123 °F) and moderately at the bottom (from 92 to 99 °F). (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer test performed on 10/8/2003. The x-axis is temperature from 70 to 105 °F. The y-axis is depth from surface ranging from 0 to 9 inches. Temperatures were taken at various intervals throughout the afternoon (12:15 p.m. to 3:15 p.m.) on this sunny day. The temperature profiles in this graph show that the surface of the slab increases from 91 °F at 12:15 p.m. to 100 °F at 1:45 p.m., but then decreases to 96 °F at 3:15 p.m. The bottom of the slab warms from 74 °F at 12:15 pm to 83 °F at 3:15 p.m. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows slab temperatures for the falling weight deflectometer test performed on 9/16/2004. The x-axis is temperature from 85 to 120 °F. The y-axis is depth from surface ranging from 0 to 9 inches. Temperatures were taken at various intervals throughout the afternoon (12:30 p.m. to 3:30 p.m.) on this sunny to partly cloudy day. The temperature profiles in this graph show that the surface of the slab increases from 111 °F at 12:30 p.m. to 120 °F at 3:30 p.m. The bottom of the slab warms from 85 °F at 12:30 p.m. to 91°F at 3:30 p.m. (1 inch = 2.54 cm. °F = 1.8 × °C +32.)
This graph shows Long-Term Pavement Program data of laboratory resilient modulus testing for one subgrade test sample. The x-axis is bulk stress from 0 to 30 psi. The y-axis is resilient modulus from 0 to 20,000 psi. Data points shown are (7, 9,500), (10, 9,600), (12, 10,100), (13, 13,500), (15, 13,000), (17, 13,900), (20, 14,200), (21, 18,000), (22, 15,800), (23, 18,200), (24, 18,200), (26, 18,100), and (27, 18,200). (1 psi = 6.89 kPa.)
This graph shows the gradation of 20 subgrade samples, designated BS06, BS02, BS**, TS07, BG**, BS01, BS04, BS03, BS**, TS13, TS15, BG02, BS**, TS01, TS05, BS301, BG01, BS05, and BS**. The x-axis is particle size on a log scale from .001 to 10 inches. The y-axis is the percentage finer by weight from 0 to 100 percent. The gradation curves for each sample are displayed. The coarsest sample is BG01, which has 7 percent of its particles (by weight) smaller than 0.01 inches, 18 percent of its particles (by weight) smaller than 0.1 inches, and 75 percent of its particles (by weight) smaller than 1 inch. The finest sample is TS15, which has 90 percent of its particles (by weight) smaller than 0.01 inches, 95 percent of its particles (by weight) smaller than 0.1 inches, and 99 percent of its particles (by weight) smaller than 1 inch. (1 inch = 25.4 mm.)
This graph shows the gradation of granular base samples, designated BG03, BG**, BG02, BG01, and BG**. The x-axis is particle size from .001 to 10 inches. The y-axis is the percentage finer by weight from 0 to 100 percent. The gradation curves for each sample are displayed. The coarsest sample is BG01, which has 7 percent of its particles (by weight) smaller than 0.01 inches, 18 percent of its particles (by weight) smaller than 0.1 inches, and 77 percent of its particles (by weight) smaller than 1 inch. The finest sample is BG02, which has 15 percent of its particles (by weight) smaller than 0.01 inches, 56 percent of its particles (by weight) smaller than 0.1 inches, and 100 percent of its particles (by weight) smaller than 1 inch. (1 inch = 25.4 mm.)
This graph summarizes the base aggregate resilient modulus for one sample from LTPP Program laboratory testing. The x-axis is bulk stress from 0 to 120 psi. The y-axis is resilient modulus from 0 to 60,000 psi. Data points shown are (10, 14,000), (15, 16,000), (19, 18,000), (20, 20,000), (28, 25,000), (30, 26,000), (40, 32,000), (50, 36,000), (54, 36,000), (59, 39,000), (60, 40,000), (78, 48,000), (80, 50,000), and (100, 57,000). (1 inch = 25.4 mm. 1 psi = 6.89 kPa.)
This figure shows gradation of the lean concrete base samples, designated CT303, CT**, CT**, CT301, CT**, and CT302. The x axis is particle size from .001 to 10 inches. The y axis is the percentage finer by weight from 0 to 100 percent. The gradation curves for each sample are displayed. One of the coarsest samples is CT302, which has 3 percent of its particles (by weight) smaller than 0.1 in, 46 percent of its particles (by weight) smaller than 0.5 in, and 99 percent of its particles (by weight) smaller than 1 inch. The finest sample is CT**, which has 7 percent of its particles (by weight) smaller than 0.01 inches, 79 percent of its particles (by weight) smaller than 0.5 inches, and 100 percent of its particles (by weight) smaller than 1 inch. (1 inch = 25.4 mm.)
This graph shows deflection basins for multiple falling weight deflectometer test locations for case study 4 (Long-Term Pavement Performance Program test section 05-0218 on I-30 in Saline County, AR). The x-axis is drop distance from -20 to 80 inches. The y-axis is deflection from 0 to 5 mils. The figure shows that there is an irregular relationship between load positions and deflections for stations at 171.9 ft and 366.1 ft. (1 mil = 0.0254 mm. 1 inch = 25.4 mm.)
This graph shows normalized maximum deflections along Long-Term Pavement Performance Program test section 05-0218. The x-axis is deflections along the section from 0 to 500 ft. The y-axis is normalized maximum deflections from 0 to 4.5 mils. Data points shown are (25, 2.7), (90, 3.5), (125, 4.2), (200, 3), (275, 3.2), (325, 3.7), (425, 3.2), and (490, 3.6). (1 ft = 0.305 m. 1 mil = 0.0254 mm.)
This graph shows k-values along the section. The x-axis is location from 0 to 500 ft. The y-axis is k-value from 0 to 600 psi/inch. Data points shown are (25, 420) (75, 400) (125, 175) (225, 500) (275, 325) (325, 300) (400, 350), and (490, 210). (1 ft = 0.305 m. 1 psi/inch = 0.263 kPa/mm.)
This graph shows the radius of relative stiffness along the Long-Term Pavement Performance Program test section 05-0218. The x-axis is distance along the section from 0 to 500 ft. The y-axis is radius of relative stiffness from 0 to 45 inches. Data points shown are (25, 30), (75, 27), (125, 38), (225, 26), (275, 32), (325, 30), (400, 31), and (490, 37). (1 inch = 25.4 mm. 1 ft = 0.305 m.)
This graph shows portland cement concrete elastic modulus along the section. The x-axis is distance along the section from 0 to 500 ft. The y-axis is elastic modulus from 0 to 10 million psi. Data points shown are (25, 9 million), (75, 5,900,000), (125, 9,500,000), (200, 6,100,000), (275, 8,300,000), (325, 5,900,000), (400, 7,900,000), and (490, 9,200,000). (1 psi = 6.89 kPa. 1 ft = 0.305 m.)
This graph shows load transfer efficiency (LTE) for different years at different testing locations along the section. The x-axis is location from 0 to 500 ft. The y-axis is LTE from 0 to 100 percent. The graph shows that the LTE percentage is lower during the colder test dates (11/14/1996 and 4/15/1999) because of poor joint performance. Testing during warmer temperatures (7/26/2001, 10/8/2003, and 9/16/2004) show higher and more acceptable LTE values because the joints are better locked. (1 ft = 0.305 m.)
This figure shows Y-intercepts from void detection test results. The x-axis is distance along the section from 0 to 500 ft. The y-axis is relative size of voids from -2 to 26 mils. The majority of data points in the 11/14/1996 and 4/15/1999 tests are between 2 and 24 mils relative size void, indicating possible voids. The majority of data points in the 7/26/2001, 10/8/2003, and 9/16/2004 tests are below 2 mils, indicating voids are most likely not present. (1 mil = 0.0254 mm. 1 ft = 0.305 m.)
This graph summarizes the predicted reliabilities for surface rutting of hot mix asphalt (HMA) overlay. The x-axis shows HMA overlay thickness ranging from 8 to 16 inches, and the y-axis shows predicted reliability from 0 to 100 percent. Three analyses are shown. Analyses 1 and 3 are almost identical beginning at about 15 percent for a 9-inch overlay, 30 percent for a 11-inch overlay, 73 percent for a 13-inch overlay, and 95 percent for a 15-inch overlay. Analysis 2 begins slightly lower at 12 percent for a 9-inch overlay, 26 percent for a11-inch overlay, 71 percent for a 13-inch overlay, and 95 percent for a 15-inch overlay. (1 inch = 25.4 mm.)
This screen capture shows the “Rehabilitation” screen for jointed portland cement concrete over hot mix asphalt. It shows Rigid Rehabilitation with entries for Existing Distress and Foundation Support.
This graph shows joint faulting versus time for the whitetopping design for case study 5 (Long-Term Pavement Performance Program test section 30-0113). The x-axis is pavement age from 0 to 26 years. The y-axis is faulting from 0 to 0.14 inches. Three joint faulting curves are shown. The first curve, labeled “faulting,” begins at 0 years and increases slowly to 0.015 inches after 25 years. The second curve, labeled “faulting at specified reliability,” begins at 0.02 inches at 0 years and increases slowly to 0.043 inches after 25 years. The third curve is the “faulting limit” curve, and it is represented by a straight line at 0.12 inches for the entire 25 years. (1 inch = 2.54 cm.)
This graph shows transverse cracking versus time for the whitetopping design for case study 5 (Long-Term Pavement Performance Program test section 30-0113). The x-axis is pavement age from 0 to 26 years. The y-axis is pavement slabs cracked from 0 to 100 percent. Three transverse cracking curves are shown. The first curve, labeled “percent slabs cracked,” begins at 0 percent at 0 years and increases slowly to 5 percent after 25 years. The second curve, labeled “cracking at specified reliability,” begins at 4 percent cracking at 0 years and slowly increases to 12 percent after 25 years. The third curve is the “cracking limit” curve, and it is represented by a straight line at 15 percent for the entire 25 years.
This graph shows International Roughness Index (IRI) versus time for the whitetopping design for case study 5 (Long-Term Pavement Performance Program test section 30-0113). The x-axis is pavement age from 0 to 26 years. The y-axis is IRI from 0 to 300 inches/mi. Three IRI curves are shown. The first curve, denoted as “IRI,” begins at 60 inches/mi at 0 years and increases slowly to 100 inches/mi after 25 years. The second curve, denoted as “IRI at specified reliability,” begins at 90 inches/mi at 0 years and slowly increases to 135 inches/mi after 25 years. The third curve is the “IRI limit” curve, and it is represented by a straight line at 170 inches/mi for the entire 25 years. (1 inch/mi = 0.0158 m/km.)
This diagram shows the pavement structure used for the four case study evaluations. The bottom layer is shown to be “A-2-6 Subgrade Layer.” The next layer up is an 8.4-inch “A-1-b Base Layer.” The next layer is a 6-inch “Asphalt Concrete” layer. Finally, the surface is a 7-inch portland cement concrete overlay. (1 inch = 25.4 mm.)
This graph shows the monthly k-values provided within the Mechanistic-Empirical Pavement Design Guide output for the four case study evaluations. The x-axis is pavement age from 0 to 300 mo. The y-axis is k-value from 0 to 400 psi. Four wave-like lines are shown in the graph, each extending across the 300-month time period. The highest line, labeled “Base mod equals 2 million psi, no back k,” has a k-value wavelength from 280 to 375 psi/inch. The next highest line, labeled “Base mod equals 25,000 psi, no back k,” has a k-value wavelength from 190 to 230 psi/inch. The next highest line, labeled “Base mod equals 2 million psi, back k equals 100 psi/inch,” has a k-value wavelength of 80 to 100 psi/inch. Finally, the lowest line, labeled “Base mod equals 25,000 psi, back k equals 100 psi/inch,” has a k-value wavelength of 75 to 100 psi. (1 psi = 6.89 kPa. 1 psi/inch = 0.263 kPa/mm.)
This diagram shows the schematic equivalent pavement structure used within the Mechanistic-Empirical Pavement Design Guide to calculate the pavement response for whitetopping. It includes two side-by-side illustrative structures. The structure on the left is the portland cement concrete (PCC) overlay for hot mix asphalt (HMA) pavements. It shows four layers, beginning at the bottom with the subgrade (Esubgrade), then the granular, stabilized base (Ebase), then the existing HMA layer, and finally the PCC overlay surface (Epcc_overlay). The structure on the right is the equivalent structure analyzed. It shows three layers, beginning with the bottom layer (“combined k-value equals f(Ebase, Esubgrade)”), then the intermediate layer (“Ebase equals f(EHMA existing)”), and finally the surface layer (“Eslab equals f(Epcc_overlay)”).
This screen capture shows the structure input screen for hot mix asphalt over jointed portland cement concrete pavement rehabilitation. It shows input columns for layer, type, material, and thickness. (1 inch = 25.4 mm.)
This screen capture shows the existing distress input in the “Rehabilitation” screen. It shows areas for existing distress and foundation support. (1 psi/inch = 0.263 kPa/mm.)
This graph summarizes the transverse cracking distress data for Long-Term Pavement Performance Program project 19-0659. The x-axis is the testing date ranging from August 1987 to April 2007. The y-axis is cracking length from 0 to 600 ft. Two lines are graphed, one representing the cracking amount recorded as part of a manual survey, the other representing cracking amount recorded via photographic survey. The manual cracking graph begins at 200 ft in 1992, decreases to 90 ft in 1997, peaks at 210 ft at 2001, and then drops to 0 ft in 2005, probably as a result of maintenance or repair work. The photographic cracking graph begins at 0 ft of cracking in 1989, increases to 210 ft of cracking in 2000, increases considerably to 490 ft in 2001, and then decreases to 0 ft in 2003. (1 ft = 0.305 m.)
This graph summarizes the Long-Term Pavement Performance Program laboratory-measured subgrade resilient modulus for five subgrade samples, designated TS01, TS18, TS12, TS08, and TS09. The x-axis is bulk stress from 0 to 30 psi. The y-axis is resilient modulus from 0 to 30,000 psi. The figure shows the resilient modulus decreases as the bulk stress increases. For instance, in one scenario, sample TS09 decreases from 14,500 psi at 8 psi bulk stress to 12,500 psi at 16 psi bulk stress. (1 psi = 6.89 kPa.)
This graph summarizes hot mix asphalt resilient modulus testing. The x-axis is temperature from 0 to 110 °F. The y-axis is resilient modulus from 1,000 to 10 million psi. The instantaneous modulus values for the binder and surface layers are similar, with data points at (40, 5 million), (76, 1 million), and (104, 500,000). The total modulus values for the binder layer have data points of (40, 9,700,000), (76, 5 million), and (104, 1,100,000). The total modulus values for the surface layer have data points of (40, 8 million), (76, 5 million), and (104, 900,000). (1 psi = 6.89 kPa. °F = 1.8 × °C +32.)
This graph shows the normalized deflection plot for 2007 mid-lane deflection basins. The x-axis is the station from 0 to 500 ft. The y-axis is the 9,000-lb normalized deflection from 0 to 5 mils. Loads tested were at 6,000, 9,000, 12,000, and 15,000 lb. The graph shows that among all stations, the deflections are fairly uniform, ranging from 2.75 mils to 3.75 mils. (1 mil = 0.0254 mm. 1 lb = 0.454 kg. 1 ft = 0.305 m.)
K subscript 0 equals the quotient of v divided by the sum of 1 minus v, end sum, end quotient.
M subscript R equals product of k subscript 1 times p subscript a times quantity of Theta divided by p subscript a, end quantity to the k subscript 2 power, times the quantity sum of, the quotient of tau subscript Oct divided by p subscript a, end quotient, plus 1, end sum, end quantity to the k subscript 3 power, end product.
This graph shows the estimated constitutive model for subgrade resilient modulus, based on test data on eight subgrade samples (BS02, BS03, BS05, BS07, BS08, BS09, BS11, and BS12). The x-axis is bulk stress from 0 to 30 psi. The y-axis is resilient modulus from 0 to 12,000 psi. The constitutive model has the following sets of data points-for level 1, (8, 4000), (10, 4,300), (12, 4,600), (14, 4,800), (16, 4,950); for level 2, (14, 6,100), (16, 6,150), (18, 6,200), (20, 6,200), (22, 6,200); and for level 3, (20, 8,100), (22, 8,000), (24, 7,950), (26, 7,900), (28, 7,800). (1 psi = 6.89 kPa.)
This graph provides a comparison of subgrade laboratory resilient modulus with predicted resilient modulus. The x-axis is measured resilient modulus from 0 to 25,000 psi. The y-axis is predicted resilient modulus from 0 to 25,000 psi. Using test data for five subgrade samples (BSX07, BSX05, BSX06, BSX08, and BSX09), the figure shows very good agreement between the predicted and the measured resilient modulus, with all data points tightly arranged about the line of equality. (1 psi = 6.89 kPa.)
M subscript R equals 26 times k-value to the 1.284 power.
This figure includes four equations for various strength and elastic modulus correlations. The first reads: E subscript PCC equals 33 p to the 3 divided by 2 power times the quantity f apostrophe subscript c end quantity to the one-half power. The second reads: MR equals 9.5 times the quantity f apostrophe subscript c end quantity to the one-half power. The third reads: MR equals 1.02 times the quantity f apostrophe subscript t end quantity plus 117. The fourth reads: MR equals 43.5 times the quotient of E subscript PCC divided by 10 to the 6 power, end quotient, plus 488.5.
ATAF equals 10 to the power: slope times the quantity T subscript r minus T subscript m, end quantity, end power.
This graph shows the illustration of HMA dynamic modulus (E*) master curve from the Mechanistic-Empirical Pavement Design Guide design software. The x-axis is the log scale of reduced time, ranging from -6 to 6. The y-axis is E* from 0 to 4 million psi. The modulus curve is s-shaped. It begins at 3,500,000 psi at a log(reduced time) of -5.5, declines smoothly to 600,000 psi at a log(reduced time) of 0, and then levels off to nearly 0 psi at a log(reduced time) of 5. (1 psi = 6.89 kPa.)
This screen capture shows the unbound layer input screen. Shown is “Unbound Layer-Layer #5.” It has areas for “Input Level,” “Analysis Type,” and “Material Property.”
This graph summarizes the overlay thickness determination for analysis 1 using the Mechanistic-Empirical Pavement Design Guide design program. The x-axis is hot mix asphalt overlay thickness from 2 to 19 inches. The primary y-axis (left side of the graph) is predicted thermal cracking from 0 to 1,800 ft, while the secondary y-axis (right side of the graph) is predicted reliability from 0 to 100 percent. The predicted thermal cracking curve begins at 1,600 ft for a 2-inch overlay, slowly declines to 850 ft for a 17-inch overlay, and decreases rapidly to 120 ft for an 18-inch overlay. The corresponding predicted reliability curve begins at 2 percent for a 2-inch overlay, increases steadily to 80 percent for a 17-inch overlay, and increases rapidly to 100 percent for an 18-inch overlay. (1 inch = 2.54 cm.)
This graph shows top-down cracking distress prediction from the Mechanistic-Empirical Pavement Design Guide design program for analysis 1. The x-axis is pavement age from 0 to 264 mo, and the y-axis is longitudinal cracking from 0 to 3,000 ft/mi. Graphed are the surface, depth, surface at reliability, and design limit. The depth (0.5 inches) and surface remain near 0 cracking for 240 mo. The surface at the selected reliability begins at 300 ft/mi longitudinal cracking and increases about 50 ft/mi with each 12 months progressively. The design limit is set at 2,000 ft/mi. (1 ft/mi = 0.19 m/km.)
This graph summarizes the k-values with and without entering dynamic k-value. The x-axis is months from January to December. The y-axis is k-value from 0 to 300 psi. Analysis 2 begins in January at 240 psi/inch, slowly drops off until 210 psi/inch is reached in July, and then rises again to 240 psi/inch in December. Analysis 1 begins in January at 220 psi/inch, slowly drops off until 195 psi/inch is reached in July, and then rises again to 220 psi/inch in December. A single data point for backcalculation input is shown in May at 190 psi/inch. (1 psi/inch = 0.263 kPa/mm.)
This graph summarizes the k-values with changing input dynamic k-value (analysis 4 assumes a k-value of 189 psi/inch, while analysis 5 assumes a k-value of 125 psi/inch). The x-axis is months from January to December. The y-axis is k-value from 0 to 300 psi/inch. The plots for the two series of data (analysis 4 and analysis 5) are on top of each other. They begin in January at 220 psi/inch, slowly drop off until 200 psi/inch is reached in July, and then rise to 220 psi/inch in December. A single data point for backcalculation input is shown in May at 190 psi/inch. (1 psi/inch = 0.263 kPa/mm.)
This graph is a copy of figure 103 but includes a summary of k-values for analysis 6, in which the subgrade modulus is reduced from 14,000 to 5,300 psi. The analysis 6 k-value plot begins in January at 120 psi/inch, slowly drops off until 110 psi/inch is reached in July, and then rises to 120 psi/inch in December. A single data point for backcalculation input is shown in May at 190 psi/inch. (1 psi/inch = 0.263 kPa/mm.)
This graph summarizes the k-values with changing subgrade modulus (analysis 1, which uses a subgrade modulus of 14,000 psi versus analysis 3, which uses a subgrade modulus of 9,500 psi). The x-axis is months from January to December. The y-axis is k-value from 0 to 300 psi/inch. The analysis 1 plot begins in January at 220 psi/inch, slowly drops off until 195 psi/inch is reached in July, and then rises to 220 psi/inch in December. The analysis 3 plot begins in January at 165 psi/inch, slowly drops off until 145 psi/inch is reached in July, and then rises to 165 psi/inch in December. A single data point for backcalculation input is shown in May at 190 psi/inch. (1 psi/inch = 0.263 kPa/mm.)
This graph shows a comparison of calculated k-value data sources. The x-axis is months from January to December. The y-axis is k-value from 0 to 300 psi/inch. Two monthly k-value curves are shown. The first curve, denoted as “cracking summary,” begins in January at 220 psi/inch, slowly drops off until 195 psi/inch is reached in July, and then rises to 220 psi/inch in December. The second curve, denoted as “monthly season pattern,” begins in January at 205 psi/inch, decreases slightly in February and March, drops to 120 psi/inch in April, increases sharply to 185 psi/inch in May (this data point is circled and labeled “Dynamic k-value input”), remains near this level until September, drops to 130 psi/inch in November, and then increases to 140 psi/inch in December. (1 psi/inch = 0.263 kPa/mm.)
This graph shows the influence of base layer on k-value. (Analysis 1 assumes no base, analysis 4 assumes a base modulus of 25,000 psi, and analysis 7 assumes a base modulus of 35,000 psi.) The x-axis is months from January to December. The y-axis is k-value from 0 to 300 psi/inch. The analysis 4 plot begins in January at 220 psi/inch, slowly drops off until 200 psi/inch is reached in July, and then rises to 227 psi/inch in December. The analysis 7 plot lies just above the analysis 4 plot, and the analysis 1 plot lies on analysis 4 plot. (1 psi/inch = 0.263 kPa/mm.)
This graph shows portland cement concrete (PCC) dynamic modulus over time. The x-axis is mo, October through September, for a total time period of 7 years. The y-axis is PCC dynamic elastic modulus from 0 to 12 million psi. Five PCC modulus curves are shown: A1 with a design static modulus of 4.434 million psi, A8 with a design static modulus of 7.919 million psi, A9 with a design static modulus of 6.335 million psi, A10 with a design static modulus of 3.801 million psi, and A11 with a design static modulus of 3.167 million psi. Three of the curves show a constant dynamic modulus over time-A1 at about 5.2 million psi, A10 at about 4.5 million psi, and A11 at about 4.1 million psi. The curve for A8 begins at about 8.9 psi and increases to about 9.5 million psi. The curve for A9 begins at about 7.4 million psi and increases to about 7.75 million psi. (1 million psi = 6,890 MPa.)
This graph shows hot mix asphalt (HMA) modulus over time. The x-axis is months, October through April, for a total time period of 7 years. The y-axis is HMA modulus from 0 to 1,400,000 psi. The modulus curve is wave-like, with lows of between 400,000 and 450,000 psi occurring in the summer months and highs of about 1,150,000 psi occurring in the winter months. (1 psi = 6.89 kPa.)
