FHWA Research And Technology Evaluation: Gusset Plates Final Report

On August 1, 2007, the I–35W Mississippi River Bridge (I–35W Bridge) in Minneapolis, MN, collapsed. The National Transportation Safety Board (NTSB) turned to the Federal Highway Administration (FHWA) to provide technical expertise during their investigation. In response, NTSB issued recommendations to FHWA and the American Association of State Transportation Officials (AASHTO) to prevent similar catastrophic bridge failures. An FHWA research project to assess the performance and design of steel gusset plate connections—referred to in this report as the Gusset Plate Project—facilitated actions that addressed one of the final NTSB recommendations. The main goal of the project was to improve bridge safety by providing research and guidance on gusset plates used to connect main load carrying members. As part of the FHWA Research and Technology (R&T) program evaluation, FHWA decided to evaluate the Gusset Plate Project to better understand how FHWA’s investment in gusset plate research has affected the design and rating of gusset plates. This report documents the findings of a summative evaluation of the Gusset Plate Project. The report focuses on outcomes resulting from collaboration between FHWA and NTSB.  The full report is available online at https://www.fhwa.dot.gov/publications/research/randt/evaluations/17039/17039.pdf