Integrating Load Testing in the Restoration of a Curved Steel Girder Bridge Damaged by Overheight Vehicle Impact

Overheight vehicle impact is a major problem that can cause considerable damage to bridges. Bridge damage often causes lifeline infrastructure to be closed to traffic and long repair times before reopening to traffic. Fracture critical steel bridges are particularly vulnerable to impact damage. As such, they often require extensive strengthening or replacement. Repair, strengthening, or replacement of fracture critical steel bridges is a complex process that requires specialized knowledge and skills. A proper evaluation of the overall bridge performance is essential before restoring the bridge back to service and to ensure safety. This paper presents the different steps used to restore the extensive damage to a fracture critical curved steel bridge. The work presented describes the inspection, analysis, and unique construction techniques to restore the bridge to its original condition. Instrumentation and field load tests were conducted at various stages to ensure proper performance of the repaired bridge. The removal of the damaged segment and the construction and installation of a new segment is fully described along with instrumentation, monitoring, and load test results before and after the repair. The test results are presented and compared with three-dimensional finite element analysis to demonstrate the effect of the repair. The repair effect evaluation framework with load test is effective and can be promoted as a customary practice in the restoration scheme after an overheight vehicle impact.