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Cross-frames are important structural components that serve many functions throughout the service life of steel I-girder bridges. Under repetitive load cycles caused by heavy truck passages, cross-frames and their connections can be susceptible to load-induced fatigue cracking if not properly designed.

The TRB National Cooperative Highway Research Program'sNCHRP Research Report 962: Proposed Modification to AASHTO Cross-Frame Analysis and Design addresses knowledge gaps in an attempt to improve the reliability and economy of cross-frames in steel I-girder bridges and produces quantitatively based methodologies and design guidelines.

Appendices B through F provide examples of cross-frame design for a straight bridge and a curved bridge as well as a comprehensive overview of the work completed in Phases I, II, and III of the project. Appendix A, Proposed Modifications to AASHTO LRFD, will be published by AASHTO.

Appendix B

Appendix C

Appendix D

Appendix E

Appendix F


Suggested Citation

National Academies of Sciences, Engineering, and Medicine. 2021. Proposed Modification to AASHTO Cross-Frame Analysis and Design. Washington, DC: The National Academies Press.

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Publication Info

156 pages |  8.5 x 11 |  Paperback
ISBN: 978-0-309-67373-0

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