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Bridges & Structures

Comprehensive Design Example for Prestressed Concrete (PSC) Girder Superstructure Bridge

Design Step 5 Design of Superstructure


Design Step 5.3 - Unfactored and Factored Load Effects


Design Step 5.3.1


Summary of loads

The dead load moments and shears were calculated based on the loads shown in Design Step 5.2. The live load moments and shears were calculated using a generic live load analysis computer program. The live load distribution factors from Design Step 5.1 are applied to these values.

Table 5.3-1 - Summary of Unfactored Moments

Interior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Noncomposite Composite Live Load + IM
Girder Slab and Haunch
(k-ft)
Exterior Diaphragm
(k-ft)
Total Noncomp.
(k-ft)
Parapet
(k-ft)
FWS
(k-ft)
Positive HL-93
(k-ft)
Negative HL-93
(k-ft)
**
(k-ft)
***
(k-ft)
0 47 0 0 0 0 0 0 0 0
1.0 108 61 62 3 125 9 12 92 -11
5.5 368 322 325 14 661 46 62 476 -58
11.0 656 609 615 28 1,252 85 114 886 -116
16.5 909 863 871 42 1,776 118 158 1,230 -174
22.0 1,128 1,082 1,093 56 2,230 144 193 1,509 -233
27.5 1,313 1,267 1,279 70 2,616 164 220 1,724 -291
33.0 1,464 1,417 1,432 84 2,933 177 237 1,882 -349
38.5 1,580 1,534 1,549 98 3,181 183 246 1,994 -407
44.0 1,663 1,616 1,633 111 3,360 183 246 2,047 -465
49.5 1,711 1,664 1,681 125 3,471 177 237 2,045 -523
54.5 1,725 1,679 1,696 138 3,512 165 222 2,015 -576
55.0 1,725 1,678 1,695 137 3,511 164 220 2,010 -581
60.5 1,705 1,658 1,675 123 3,456 144 194 1,927 -640
66.0 1,650 1,604 1,620 109 3,333 118 159 1,794 -698
71.5 1,562 1,515 1,531 95 3,141 86 115 1,613 -756
77.0 1,439 1,392 1,407 81 2,880 46 62 1,388 -814
82.5 1,282 1,236 1,248 67 2,551 1 1 1,124 -872
88.0 1,091 1,044 1,055 53 2,152 -52 -69 825 -1,124
93.5 865 819 827 39 1,686 -110 -148 524 -1,223
99.0 606 560 565 25 1,150 -176 -236 297 -1,371
104.5 312 266 268 11 546 -248 -332 113 -1,663
108.0 110 61 62 3 125 -297 -398 33 -1,921
109.0 47 0 0 0 0 -311 -418 15 -2,006
Span2-0 - 0 0 0 0 -326 -438 0 -2,095

* Distance from the centerline of the end bearing
** Based on the simple span length of 110.5 ft. and supported at the ends of the girders. These values are used to calculate stresses at transfer.
*** Based on the simple span length of 109 ft. and supported at the centerline of bearings. These values are used to calculate the final stresses.

Table 5.3-2 - Summary of Factored Moments

Interior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Strength I
(k-ft)
Service I ** Service III **
NC
(k-ft)
Comp.
(k-ft)
NC
(k-ft)
Comp.
(k-ft)
0 0 0 0 0 0
1.0 346 125 112 125 94
5.5 1,809 661 584 661 488
11.0 3,394 1,252 1,085 1,252 908
16.5 4,756 1,776 1,506 1,776 1,260
22.0 5,897 2,230 1,846 2,230 1,544
27.5 6,821 2,616 2,108 2,616 1,763
33.0 7,536 2,933 2,296 2,933 1,920
38.5 8,063 3,181 2,423 3,181 2,024
44.0 8,381 3,360 2,477 3,360 2,067
49.5 8,494 3,471 2,459 3,471 2,050
54.5 8,456 3,512 2,402 3,512 1,999
55.0 8,440 3,511 2,394 3,511 1,992
60.5 8,163 3,456 2,265 3,456 1,880
66.0 7,690 3,333 2,070 3,333 1,712
71.5 7,027 3,141 1,813 3,141 1,490
77.0 6,181 2,880 1,497 2,880 1,219
82.5 5,158 2,551 1,126 2,551 901
88.0 3,967 2,152 -1,245 2,152 -1,020
93.5 2,664 1,686 -1,481 1,686 -1,237
99.0 -1,535 1,150 -1,783 1,150 -1,509
104.5 -3,035 546 -2,242 546 -1,910
108.0 -4,174 125 -2,616 125 -2,232
109.0 -4,525 0 -2,734 0 -2,333
Span 2 - 0 -4,729 0 -2,858 0 -2,439

Load Factor Combinations
Strength I = 1.25(DC) + 1.5(DW) + 1.75(LL + IM)
Service I = 1.0[DC + DW + (LL + IM)]
Service III    = 1.0(DC + DW) + 0.8(LL + IM)

* Distance from the centerline of the end bearing
** For service limit states, moments are applied to the section of the girder, i.e. noncomposite or composite, that resists these moments. Hence, noncomposite and composite moments have to be separated for service load calculations.

Table 5.3-3 - Summary of Unfactored Shear

Interior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Noncomposite Composite Live Load + IM
Girder
(k)
Slab and Haunch
(k)
Exterior Diaphragm
(k)
Total Noncomp.
(k)
Parapet
(k)
FWS
(k)
Positive
HL-93
(k)
Negative
HL-93
(k)
0 61.6 62.2 2.5 126.4 8.9 12.0 113.3 -12.9
1.0 60.5 61.1 2.5 124.1 8.7 11.7 111.7 -12.9
5.5 55.4 55.9 2.5 113.9 7.7 10.4 104.3 -13.0
11.0 49.2 49.7 2.5 101.4 6.5 8.8 95.5 -13.4
16.5 43.0 43.4 2.5 88.9 5.4 7.2 86.9 -15.9
22.0 36.7 37.1 2.5 76.4 4.2 5.6 78.7 -20.6
27.5 30.5 30.8 2.5 63.9 3.0 4.0 70.8 -26.0
33.0 24.3 24.6 2.5 51.4 1.8 2.4 63.1 -32.8
38.5 18.1 18.3 2.5 38.9 0.6 0.8 55.9 -39.8
44.0 11.9 12.0 2.5 26.4 -0.6 -0.8 48.9 -46.8
49.5 5.7 5.7 2.5 13.9 -1.8 -2.4 42.4 -54.0
54.5 0 0 -2.5 -2.5 -2.9 -3.8 36.8 -60.5
55.0 -0.6 -0.6 -2.5 -3.7 -3.0 -4.0 36.2 -61.2
60.5 -6.8 -6.9 -2.5 -16.2 -4.2 -5.6 30.4 -68.4
66.0 -13.0 -13.1 -2.5 -28.7 -5.3 -7.2 25.0 -75.7
71.5 -19.2 -19.4 -2.5 -41.2 -6.5 -8.8 20.0 -82.9
77.0 -25.4 -25.7 -2.5 -53.7 -7.7 -10.4 15.4 -90.1
82.5 -31.7 -32.0 -2.5 -66.1 -8.9 -12.0 11.3 -97.3
88.0 -37.9 -38.3 -2.5 -78.6 -10.1 -13.6 8.2 -104.3
93.5 -44.1 -44.5 -2.5 -91.1 -11.3 -15.1 5.5 -111.3
99.0 -50.3 -50.8 -2.5 -103.6 -12.5 -16.7 3.2 -118.0
104.5 -56.5 -57.1 -2.5 -116.1 -13.7 -18.3 1.2 -124.7
108.0 -60.5 -61.1 -2.5 -124.1 -14.4 -19.4 0.4 -128.7
109.0 -61.6 -62.2 -2.5 -126.4 -14.6 -19.6 0.2 -129.9
Span 2 - 0 0 0 0 0 -14.8 -19.9 0 -131.1

* Distance from the centerline of the end bearing

Table 5.3-4 - Summary of Factored Shear

Interior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Strength I
(k)
Service I
(k)
Service III
(k)
0 385.4 260.6 237.9
1.0 379.0 256.2 233.8
5.5 350.0 236.2 215.4
11.0 315.1 212.1 193.0
16.5 280.7 188.3 170.9
22.0 246.8 164.8 149.1
27.5 213.4 141.6 127.5
33.0 180.6 118.7 106.1
38.5 148.3 96.2 85.0
44.0 116.7 74.0 64.2
49.5 85.7 52.1 43.6
54.5 -118.4 -69.7 -57.6
55.0 -121.3 -71.8 -59.6
60.5 -153.5 -94.3 -80.6
66.0 -185.7 -116.9 -101.7
71.5 -217.9 -139.4 -122.8
77.0 -250.0 -161.8 -143.8
82.5 -282.0 -184.3 -164.8
88.0 -313.8 -206.6 -185.7
93.5 -345.4 -228.8 -206.6
99.0 -376.8 -250.9 -227.3
104.5 -407.9 -272.8 -247.8
108.0 -427.4 -286.6 -260.8
109.0 -433.0 -290.5 -264.5
Span 2 - 0 -277.8 -165.8 -139.6

Load Factor Combinations

* Distance from the centerline of the end bearing

Strength I = 1.25(DC) + 1.5(DW) + 1.75(LL + IM)
Service I = 1.0[DC + DW + (LL + IM)]
Service III    = 1.0(DC + DW) + 0.8(LL + IM)

Table 5.3-5 - Summary of Unfactored Moments

Exterior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Noncomposite Composite Live Load + IM
Girder Slab and Haunch
(k-ft)
Exterior Diaphragm
(k-ft)
Total Noncomp.
(k-ft)
Parapet
(k-ft)
FWS
(k-ft)
Positive HL-93
(k-ft)
Negative HL-93
(k-ft)
**
(k-ft)
***
(k-ft)
0 47 0 0 0 0 0 0 0 0
1.0 108 61 55 1 117 9 8 93 -11
5.5 368 322 288 7 616 46 41 482 -59
11.0 656 609 545 14 1,168 85 77 897 -118
16.5 909 863 771 21 1,655 118 106 1,245 -177
22.0 1,128 1,082 967 28 2,076 144 130 1,528 -236
27.5 1,313 1,267 1,132 35 2,434 164 148 1,746 -294
33.0 1,464 1,417 1,267 42 2,726 177 160 1,906 -353
38.5 1,580 1,534 1,371 49 2,954 183 165 2,019 -412
44.0 1,663 1,616 1,445 56 3,117 183 166 2,073 -471
49.5 1,711 1,664 1,488 63 3,215 177 160 2,071 -530
54.5 1,725 1,679 1,501 69 3,248 165 149 2,041 -583
55.0 1,725 1,678 1,501 68 3,247 164 148 2,035 -589
60.5 1,705 1,658 1,482 61 3,202 144 130 1,951 -648
66.0 1,650 1,604 1,434 54 3,092 118 107 1,816 -706
71.5 1,562 1,515 1,355 48 2,917 86 77 1,633 -765
77.0 1,439 1,392 1,245 41 2,678 46 42 1,406 -824
82.5 1,282 1,236 1,105 34 2,374 1 1 1,139 -883
88.0 1,091 1,044 934 27 2,005 -52 -47 836 -1,138
93.5 865 819 732 20 1,571 -110 -100 531 -1,238
99.0 606 560 500 13 1,072 -176 -159 300 -1,389
104.5 312 266 238 6 509 -248 -224 114 -1,683
108.0 110 61 55 1 117 -297 -268 33 -1,945
109.0 47 0 0 0 0 -311 -281 15 -2,031
Span 2 - 0 - 0 0 0 0 -326 -294 0 -2,121

* Distance from the centerline of the end bearing
** Based on the simple span length of 110.5 ft. and supported at the ends of the girders. These values are used to calculate stresses at transfer.
*** Based on the simple span length of 109 ft. and supported at the centerline of bearings. These values are used to calculate the final stresses.

Table 5.3-6 - Summary of Factored Moments

Exterior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Strength I
(k-ft)
Service I ** Service III **
NC
(k-ft)
Comp.
(k-ft)
NC
(k-ft)
Comp.
(k-ft)
0 0 0 0 0 0
1.0 331 117 110 117 91
5.5 1,734 616 570 616 473
11.0 3,251 1,168 1,059 1,168 879
16.5 4,554 1,655 1,469 1,655 1,220
22.0 5,644 2,076 1,801 2,076 1,496
27.5 6,524 2,434 2,057 2,434 1,708
33.0 7,203 2,726 2,242 2,726 1,861
38.5 7,702 2,954 2,368 2,954 1,964
44.0 8,001 3,117 2,422 3,117 2,007
49.5 8,103 3,215 2,407 3,215 1,993
54.5 8,061 3,248 2,355 3,248 1,947
55.0 8,047 3,247 2,347 3,247 1,940
60.5 7,793 3,202 2,226 3,202 1,836
66.0 7,351 3,092 2,041 3,092 1,678
71.5 6,727 2,917 1,796 2,917 1,469
77.0 5,928 2,678 1,494 2,678 1,213
82.5 4,961 2,374 1,140 2,374 912
88.0 3,834 2,005 -1,237 2,005 -1,009
93.5 2,605 1,571 -1,448 1,571 -1,201
99.0 -1,547 1,072 -1,723 1,072 -1,445
104.5 -2,954 509 -2,154 509 -1,818
108.0 -4,031 117 -2,510 117 -2,121
109.0 -4,364 0 -2,623 0 -2,217
Span 2 - 0 -4,560 0 -2,741 0 -2,317

Load Factor Combinations
Strength I = 1.25(DC) + 1.5(DW) + 1.75(LL + IM)
Service I = 1.0[DC + DW + (LL + IM)]
Service III = 1.0(DC + DW) + 0.8(LL + IM)

* Distance from the centerline of the end bearing
** For service limit states, moments are applied to the section of the girder, i.e. noncomposite or composite, that resists these moments. Hence, noncomposite and composite moments have to be separated for service load calculations.

Table 5.3-7 - Summary of Unfactored Shear

Exterior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Noncomposite Composite Live Load + IM
Girder
(k)
Slab and Haunch
(k)
Exterior Diaphragm
(k)
Total Noncomp.
(k)
Parapet
(k)
FWS
(k)
Positive
HL-93
(k)
Negative
HL-93
(k)
0 61.6 55.1 1.3 117.9 8.9 8.1 98.4 -11.2
1.0 60.5 54.1 1.3 115.8 8.7 7.9 97.0 -11.2
5.5 55.4 49.5 1.3 106.2 7.7 7.0 90.6 -11.3
11.0 49.2 44.0 1.3 94.4 6.5 5.9 82.9 -11.6
16.5 43.0 38.4 1.3 82.6 5.4 4.8 75.5 -13.8
22.0 36.7 32.8 1.3 70.8 4.2 3.8 68.3 -17.9
27.5 30.5 27.3 1.3 59.1 3.0 2.7 61.4 -22.6
33.0 24.3 21.7 1.3 47.3 1.8 1.6 54.8 -28.5
38.5 18.1 16.2 1.3 35.5 0.6 0.5 48.5 -34.5
44.0 11.9 10.6 1.3 23.7 -0.6 -0.5 42.5 -40.7
49.5 5.7 5.1 1.3 12.0 -1.8 -1.6 36.8 -46.9
54.5 0 0 -1.3 -1.3 -2.9 -2.6 31.9 -52.6
55.0 -0.6 -0.5 -1.3 -2.3 -3.0 -2.7 31.4 -53.1
60.5 -6.8 -6.1 -1.3 -14.1 -4.2 -3.8 26.4 -59.4
66.0 -13.0 -11.6 -1.3 -25.9 -5.3 -4.8 21.7 -65.7
71.5 -19.2 -17.2 -1.3 -37.7 -6.5 -5.9 17.4 -72.0
77.0 -25.4 -22.7 -1.3 -49.4 -7.7 -7.0 13.4 -78.3
82.5 -31.7 -28.3 -1.3 -61.2 -8.9 -8.0 9.8 -84.5
88.0 -37.9 -33.9 -1.3 -73.0 -10.1 -9.1 7.2 -90.6
93.5 -44.1 -39.4 -1.3 -84.8 -11.3 -10.2 4.8 -96.6
99.0 -50.3 -45.0 -1.3 -96.5 -12.5 -11.3 2.8 -102.5
104.5 -56.5 -50.5 -1.3 -108.3 -13.7 -12.3 1.0 -108.3
108.0 -60.5 -54.1 -1.3 -115.8 -14.4 -13.0 0.4 -111.8
109.0 -61.6 -55.1 -1.3 -117.9 -14.6 -13.2 0.2 -112.8
Span 2 - 0 0 0 0 0 -14.8 -13.4 0 -113.8

* Distance from the centerline of the end bearing

Table 5.3-8 - Summary of Factored Shear

Exterior girder, Span 1 shown, Span 2 mirror image

Location*
(ft.)
Strength I
(k)
Service I
(k)
Service III
(k)
0 342.9 233.3 213.7
1.0 337.2 229.4 210.0
5.5 311.3 211.4 193.3
11.0 280.1 189.7 173.2
16.5 249.3 168.3 153.2
22.0 219.0 147.1 133.4
27.5 189.1 126.2 113.9
33.0 159.7 105.5 94.6
38.5 130.9 85.2 75.5
44.0 102.5 65.1 56.6
49.5 74.8 45.4 38.0
54.5 -101.0 -59.3 -48.7
55.0 -103.6 -61.1 -50.5
60.5 -132.4 -81.4 -69.5
66.0 -161.3 -101.8 -88.6
71.5 -190.1 -122.1 -107.7
77.0 -218.8 -142.4 -126.7
82.5 -247.5 -162.6 -145.7
88.0 -276.0 -182.8 -164.7
93.5 -304.4 -202.8 -183.5
99.0 -332.5 -222.8 -202.2
104.5 -360.4 -242.5 -220.9
108.0 -377.9 -255.0 -232.7
109.0 -382.9 -258.6 -236.0
Span 2 - 0 -237.8 -142.1 -119.3
Load Factor Combinations
Strength I = 1.25(DC) + 1.5(DW) + 1.75(LL + IM)
Service I = 1.0[DC + DW + (LL + IM)]
Service III    = 1.0(DC + DW) + 0.8(LL + IM)

* Distance from the centerline of the end bearing

Based on the analysis results, the interior girder controls the design. The remaining sections covering the superstructure design are based on the interior girder analysis. The exterior girder calculations would be identical.

Design Step 5.3.2 - Analysis of Creep and Shrinkage Effects


Design Step 5.3.2.1

The compressive stress in the beams due to prestressing causes the prestressed beams to creep. For simple span pretensioned beams under dead loads, the highest compression in the beams is typically at the bottom, therefore, creep causes the camber to increase, i.e., causes the upward deflection of the beam to increase. This increased upward deflection of the simple span beam is not accompanied by stresses in the beam since there is no rotational restraint of the beam ends. When simple span beams are made continuous through a connection at the intermediate support, the rotation at the ends of the beam due to creep taking place after the connection is established are restrained by the continuity connection. This results in the development of fixed end moments (FEM) that maintain the ends of the beams as flat. As shown schematically in Figure 5.3-1 for a two-span bridge, the initial deformation is due to creep that takes place before the continuity connection is established. If the beams were left as simple spans, the creep deformations would increase; the deflected shape would appear as shown in part b of the figure. However, due to the continuity connection, fixed end moments at the ends of the beam will be required to restrain the end rotations after the continuity connection is established as shown in part c of the figure. The beam is analyzed under the effects of the fixed end moments to determine the final creep effects.

Similar effects, albeit in the opposite direction, take place under permanent loads. For ease of application, the effect of the dead load creep and the prestressing creep are analyzed separately. Figures 5.3-2 and 5.3-3 show the creep moment for a two-span bridge with straight strands. Notice that the creep due to prestressing and the creep due to dead load result in restrained moments of opposite sign. The creep from prestressing typically has a larger magnitude than the creep from dead loads.

Figure showing the prestressed creep deformations and restraint moments for a two span girder. Part a shows the initial deformation, part b shows the final free deformation (simple span) and part c shows the final deformation and associated restraint moments for simple spans made continuous.

Figure 5.3-1 - Prestressed Creep Deformations and Restraint Moments

Figure showing the dead load creep moments. There are two figures, the upper shows the noncomposite dead load creep and the lower figure shows the dead load creep restraint moment.

Figure 5.3-2 - Dead Load Creep Moment

Figure showing the prestressed creep moment. There are two figures, the upper shows the applied prestressed creep moment and the lower shows the prestressed creep restraint moment.

Figure 5.3-3 - Prestressed Creep Moment

Shrinkage effects

The shrinkage of the pretensioned beams is different from the shrinkage of the deck slab. This is due to the difference in the age, concrete strength, and method of curing of the two concretes. Unlike creep, differential shrinkage induces stresses in all prestressed composite beams, including simple spans. The larger shrinkage of the deck causes the composite beams to sag as shown in Figure 5.3-4. The restraint and final moments are also shown schematically in the figure.

Figure showing the shrinkage moment. There are three figures, the upper provides the applied shrinkage or driving moment, the middle provides the shrinkage restraint moment and the lower shows the total shrinkage effect.

Figure 5.3-4 - Shrinkage Moment

Calculations of creep and shrinkage effects

The effect of creep and shrinkage may be determined using the method outlined in the publication entitled "Design of Continuous Highway Bridges with Precast, Prestressed Concrete Girders" published by the Portland Cement Association (PCA) in August 1969. This method is based on determining the fixed end moments required to restrain the ends of the simple span beam after the continuity connection is established. The continuous beam is then analyzed under the effect of these fixed end moments. For creep effects, the result of this analysis is the final result for creep effects. For shrinkage, the result of this analysis is added to the constant moment from shrinkage to determine the final shrinkage effects. Based on the PCA method, Table 5.3-9 gives the value of the fixed end moments for the continuous girder exterior and interior spans with straight strands as a function of the length and section properties of each span. The fixed end moments for dead load creep and shrinkage are also applicable to beams with draped strands. The PCA publication has formulas that may be used to determine the prestress creep fixed end moments for beams with draped strands.

Table 5.3-9 - Fixed End Actions for Creep and Shrinkage Effects

Figure showing the fixed end action sign convention for Table 5.3-9.

  DL Creep P/S Creep Shrinkage
Left End Span Interior Span Right End Span Left End Span Interior Span Right End Span Left End Span Interior Span Right End Span
Left Moment (1) 0 2/3(MD) MD 0 2EIΘ,/L 3EIΘ/L 0 Ms 1.5Ms
Right Moment (2)    -MD -2/3(MD) 0 -3EIΘ/L -2EIΘ/L 0 -1.5Ms -Ms 0
Left Shear (3) -MD/L 0 MD/L -3EIΘ/L2 0 3EIΘ/L2 -3Ms/2L 0 3Ms/2L
Right Shear (4) MD/L 0 -MD/L 3EIΘ/L2 0 -3EIΘ/L2 3Ms/2L 0 -3Ms/2L

Notation for Fixed End Actions

MD = maximum non-composite dead load moment
L = simple span length
Ec = modulus of elasticity of beam concrete (final)
I = moment of inertia of composite section
Θ = end rotation due to eccentric P/S force
Ms = applied moment due to differential shrinkage between slab and beam

Design Step 5.3.2.3 - Effect of beam age at the time of the continuity connection application

The age of the beam at the time of application of the continuity connection has a great effect on the final creep and shrinkage moments. As the age of the beam increases before pouring the deck and establishing the continuity connection, the amount of creep, and the resulting creep load effects, that takes place after the continuity connection is established gets smaller. The opposite happens to the shrinkage effects as a larger amount of beam shrinkage takes place before establishing the continuity connection leading to larger differential shrinkage between the beam and the deck.

Due to practical considerations, the age of the beam at the time the continuity connection is established can not be determined with high certainty at the time of design. In the past, two approaches were followed by bridge owners to overcome this uncertainty:

  1. Ignore the effects of creep and shrinkage in the design of typical bridges. (The jurisdictions following this approach typically have lower stress limits at service limit states to account for the additional loads from creep and shrinkage.)

  2. Account for creep and shrinkage using the extreme cases for beam age at the time of establishing the continuity connection. This approach requires determining the effect of creep and shrinkage for two different cases: a deck poured over a relatively "old" beam and a deck poured over a relatively "young" beam. One state that follows this approach is Pennsylvania. The two ages of the girders assumed in the design are 30 and 450 days. In case the beam age is outside these limits, the effect of creep and shrinkage is reanalyzed prior to construction to ensure that there are no detrimental effects on the structure.

For this example, creep and shrinkage effects were ignored. However, for reference purposes, calculations for creep and shrinkage are shown in Appendix C.

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Updated: 07/08/2013
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