Bridge Testing and Diagnostics for Enhanced Load Rating

Accurate bridge load rating is essential for identifying problem structures and keeping our bridges safe and in service. Measuring actual bridge response (strains and displacements) under truck loading coupled with subsequent advanced structural analysis is perhaps the most reliable way to assess bridge capacity. Coupled field load testing and analysis has been shown to lead to significantly higher load ratings than those predicted with standard American Association of State Highway and Transportation Officials (AASHTO) methods, and has the potential to save the Maine Department of Transportation (MaineDOT) and the State significant funds through more efficient use of our existing bridge inventory. Accurately load testing multiple in-service bridges can be accomplished only with specialized sensing, monitoring, and data-acquisition equipment that can be installed and used with minimal effort. The University of Maine AEWC Advanced Structures and Composites Laboratory (AEWC) has already committed to purchasing the BDI bridge diagnostics system with previously allocated Federal Highway Administration (FHWA) research funding being administered by the MaineDOT. Under the project proposed here, the AEWC will work with the MaineDOT personnel to identify critical bridges, perform diagnostic live load testing with the BDI equipment, and to analyze the load-tested bridges to develop refined rating factors.