LFD Analysis Verification - Straight Steel I Girder Bridge

The representative bridge is a straight two-lane plate girder bridge with identical four-girder cross-sections, and features continuous three spans over span lengths of 80, 100, and 80-feet along the control centerline. In this example, I-girders are modeled using a combination of member and shell elements for refined modeling. The top flange girder is connected to the deck with rigid elements, and the bridge deck is modeled using shell elements. Modular ratios of “n” and “3n” are used for the deck slab in calculating girder stiffness and modeled as time-dependent material property.

Materials:

Steel

Concrete

Loading


Library linki : https://openbrim.org/objid92cvjxra3pqo5ud5vynnj.libobj

SPECIFIC RESULTS


Longitudinal Dead Load Bending Moment Diagrams and Live Load Moment Envelopes
1) Girder 3- Non-Composite Dead Load (Form 1M)



2) Girder 4- Non-Composite Dead Load (Form 1M)


3) Girder 3- Composite Dead Load (Form 2M)


4) Girder 4- Composite Dead Load (Form 2M)


5) Girder 3- Positive Live Load Plus Impact (Form 3M)




6) Girder 3- Negative Live Load Plus Impact (Form 4M)




7) Girder 4- Positive Live Load Plus Impact (Form 3M)




8) Girder 4- Negative Live Load Plus Impact (Form 4M)





Vertical Reactions (kips)
1) Non-Composite Dead Load (Form 5R)



OpenBrIMLarsa
Girder 1Girder 2

Girder 3

Girder 4 Pier TotalGirder 1Girder 2Girder 3Girder 4 Pier Total
Pier 1

37.5253

39.7773

39.766737.4521

154.5214

37.1440.0940.1137.13154.48
Pier 2135.7755142.0142142.0141135.7758555.5796134.42143.34143.34134.42555.51
Pier 3135.7733142.0111142.0108135.7729555.5681134.41143.33143.33134.41555.49
Pier 437.452339.774139.768137.4549154.449437.1440.1040.1137.14154.48
Girder Total

346.5264

363.5767363.5597346.4557
343.11366.86366.90343.10
Bridge Total1420.119
1419.96


2) Composite Dead Load (Form 5R)


OpenBrIMLarsa
Girder 1Girder 2

Girder 3

Girder 4 Pier TotalGirder 1Girder 2Girder 3Girder 4 Pier Total
Pier 1

13.8294

9.1966

9.196613.8958

46.1184

14.179.069.0414.1846.45
Pier 248.119132.524732.525948.1226161.292348.4732.7032.7048.46162.33
Pier 348.120532.526632.526748.1206161.294448.4732.7032.7048.46162.33
Pier 413.89459.19639.196713.894446.181914.179.049.0414.1846.45
Girder Total

123.9635

83.444283.4459124.0334
125.2783.5283.49125.28
Bridge Total414.887
417.56

3) Live Load Plus Impact (Form 6R)


OpenBrIMLarsa

Girder1Girder2Girder3Girder4Girder1Girder2Girder3Girder4
Pier177.177574.200775.997776.788767.6280.9781.7566.36
Pier2105.384897.030397.7614103.947110.13120.77121.12108.54
Pier3101.772997.051197.4683100.588106.93120.16120.52105.34
Pier480.178871.489175.926979.64967.6579.0479.7666.33
Cross Frame Axial Forces (kips)
4) Live Load Plus Impact (Form 7C)
Cross-Frame at Center of Span 2 Between Girders 2 and 3

OpenBrIMLarsa

Bottom ChordDiagonalsBottom ChordDiagonals
Tension13.94249.2437.5716.49
Compression-12.4104-9.0286-5.51-11.29
Bottom Flange Lateral Moments (kip-feet)
5) Live Load Plus Impact (Form 8F)

OpenBrIMLarsa

Pier 2Center Of Span 2Pier 2Center Of Span 2
Girder 32.991.593.391.71
Girder 43.291.603.972.21
Dead Load Vertical Deflections (inch)
6) Non-Composite Dead Load (Form 9D)

OpenBrIMLarsa

0.4 Pt of Span 1Center Of Span 20.4 Pt of Span 1Center Of Span 2
Girder 3
-0.4807
-0.4991
-0.49-0.51
Girder 4
-0.4605
-0.4781
-0.46-0.48


7) Composite Dead Load (Form 9D)

OpenBrIMLarsa

0.4 Pt of Span 1Center Of Span 20.4 Pt of Span 1Center Of Span 2
Girder 3
-0.0555
-0.0668
-0.069-0.083
Girder 4
-0.0672
-0.0792-0.086-0.099