On January 20, 2017, a complete fracture of a top chord was discovered on the Delaware River Turnpike Bridge. As a result of this fracture, a stress redistribution occurred, substantially altering the forces carried by the adjacent top chord members, concrete deck, stringers, and sway bracing. The structure was immediately closed to traffic and a repair process was developed to restore the structure to its original condition. Structural monitoring was used throughout the repair process to evaluate the restoration of the loads in the structure and ultimately its ability to safely carry traffic loads. Additionally, a load test was performed on the similar sister truss on the New Jersey approach to calibrate the finite element models being used to evaluate the jacking and post-tensioning forces and design the repairs to the compromised truss on the Pennsylvania side. Finally, a load test was performed on the damaged Pennsylvania truss following the completion of the emergency repairs to provide a confirmation of behavior. This confirmation of behavior was ultimately used to help the owners make the decision to re-open the bridge to traffic. The structure was re-opened to traffic in less than seven weeks on March 9, 2017. The instrumentation remains on the bridge as of September 2017 and continues to be monitored to confirm the structure is acting as anticipated and continues to safely carry the daily traffic loads. This paper will discuss the structural monitoring that was performed during each of the repair operations and the overall impact of the monitoring on the repair process.

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