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NCHRP Report No. 725 ("Guidelines for Analysis Methods and Construction Engineering of Curved and Skewed Steel Girder Bridges") is a reference document produced by TRB’s National Cooperative Highway Research Program, which offers guidance on the appropriate level of analysis needed to determine the constructability and constructed geometry of curved and skewed steel girder bridges:
https://nap.nationalacademies.org/catalog/22729/guidelines-for-analysis-methods-and-construction-engineering-of-curved-and-skewed-steel-girder-bridges

The models below are directly taken from the report. Detailed information on their geometry is available in Appendix I:
https://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_725AppendixI.pdf


All models are available for free download at this link:
https://drive.google.com/drive/folders/124OKUIvfhV8KdlgU_bNtoi6H8vUm7r1y?usp=sharing

1. EISCR1 is a simple-span curved plate girder bridge with radial supports. It is also known as the FHWA Test Bridge (experimental results are available). 3D FEA has shown to capture much more accurately the structural behavior than simplified analysis methods.

2. EICSS12 is an existing plate girder bridge, which was constructed in Lubbock, TX. All support lines are skewed at a 59.6 degree angle. The bridge has been studied in a number of papers as it is one of the first to implement lean-on bracing techniques as developed at the University of Texas at Austin.

3. NISCS14 is a simple-span curved plate girder bridge with a span of 150-ft. and a radius of about 280-ft. for the central girder. One of the bearing lines has a 53.7 degree skew.

4. EICCR11 is an existing plate girder bridge which was constructed in Ford City, PA. It has a point of tangency at about two thirds of its length, after which the radius of curvature is equal to 324-ft. Due the tight curvature and close spacing between girders, the bridge presented challenges during its erection.

5. EISSS6 is an existing straight simple-span plate girder bridge with a 265-ft. length and a 62 degree skew at the supports. It was constructed in New York State in 2003. The cross-frames are oriented perpendicularly to the girders, and top lateral bracing provides additional stability to the structure.

6. NISCS15 a simple-span curved plate girder bridge with a 150-ft. span for the central girder. One of the bearing line has a 35 degree angle skew.

7. NISCR5 a simple-span curved plate girder bridge with radial abutments. The span is about 300-ft. and the radius of curvature for the interior girder is equal to 1,518-ft. Spacing between girders is equal to 8-ft., which is relatively narrow. 

8. NISSS54 is a 300-ft. simple-span plate girder bridge with bearing lines severely skewed at a 70 degree angle. The bridge has a staggered cross-frame arrangement.

9. NISCS37 is a simple-span curved plate girder bridge, with a central radius of curvature of 730-ft. and a span of 300-ft. One of the bearing lines has a skew of 35 degrees.

10. NISCR2 is a simple-span curved plate girder bridge with a central radius of curvature of 438-ft. and a span of 150-ft. This bridge is yet another good example to illustrate the benefits of using advanced 3D FEA versus traditional analysis methods to capture the "true" structural behavior.

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