LOAD TESTING A CFRP-REINFORCED BRIDGE

The Bridge Street Bridge Deployment Project in Southfield, Michigan, is an example of an innovative project in which bridge members are reinforced and prestressed fully with carbon fiber-reinforced polymer tendons and strands. This article describes the details and findings related to a field load test conducted on one of the project's bridges after construction completion. The object of the static load test was to evaluate structural performance under live load conditions approximating design service load levels. Static loads were applied to each span of the structure using two identical tandem rear-axle dump trucks filled to achieve a total target vehicle weight of approximately 258 kN (58,000 lb). During the load test, the existing bridge instrumentation and data acquisition system were used to measure the response to the applied loads. The response to the applied static loads was evaluated based primarily on measured concrete strains and deflection data at midspan of each instrumented beam. Results from the load test indicate that the applied loads per lane were effectively distributed to all four beams of each bridge span, the three spans exhibit similar load distribution behavior and that the actual load distribution behavior is consistent with the distribution factors derived from the provisions of the AASHTO design specifications. These findings indicate that the provisions of the AASHTO specifications can be used to predict load distribution behavior of bridge superstructure configurations similar to the one tested.