A Comparison of Prestress Losses in a Prestressed Concrete Bridge Made with High Performance Self Consolidating Concrete

This study describes the measured behavior of six prestressed bridge girders made with high strength, self-consolidating concrete. In-place strains were measured using vibrating wire strain gauges embedded in the girders. These strains were used to determine prestress losses that were compared to calculated values obtained using the 2004 and 2007 AASHTO LRFD Specifications. Results indicate that this particular SCC mix exhibits strength and stiffness characteristics that are larger than many high performance concrete mixes. The prestress losses calculated using the AASHTO design practices underestimated the measured initial elastic shortening losses and overestimated the total long term losses measured. This study shows that design practices for high strength concrete are improving, and that these procedures adequately predict the long-term prestress losses for high strength self-consolidating concrete.