Concrete Bridge Shear Load Rating Guide and Examples: Using the Modified Compression Field Theory

Federal Highway Administration2022PDFTech ReportHolt, JohnBayrak, OguzhanOkumus, PinarStavridis, AndreasMurphy, ThomasPanchal, DhavalDutta, AnimeshRandiwe, AkshayUniversity at Buffalo, BuffaloModjeski and MastersUnited States. Federal Highway AdministrationGao, LubinWarren, TuonglinhUnited States. Federal Highway AdministrationUnited StatesHighwaysBridgesShear strengthLoad and resistance factor designLoad factorDesign loadConcrete ShearLoad RatingLegal LoadsPermit LoadsLFRLRFRLFDLRFDModified Compression Field TheoryMCFTFHWA-HIF-22-025DTFH6114D00050Gao, Lubin; Warren, TuonglinhFinal ReportThis Guide provides information to load rating engineers in the application of Modified Compression Field Theory (MCFT) when load rating concrete bridges in shear. It includes a literature review of recent research on load rating and summarizes a research study on the effects of minimum shear reinforcement amounts relative to load rating. This Guide also highlights the differences in design and load rating with MCFT. Presented are flow charts with three potential controlling cases of shear strength and procedures to ascertain the limiting shear strength for a concrete element. Load rating examples are provided, illustrating the application of AASHTO provisions f or shear load rating for three concrete bridges.137