Flexural Behavior of High-Early-Strength Self-Consolidating Concrete Pretensioned Bridge Girders: Experimental Evaluation

摘要

A research program investigated the application of high-early-strength self-consolidating concrete (SCC) for precast, prestressed bridge girders. The SCC and conventional concrete (CC) in mixtures had a target 16-h release strength of 34 MPa (5,000 psi). Testing was performed to evaluate the flexural response and bond performance of the girders. This included assessing and comparing camber and deflection, moment-curvature, cracking moment, nominal moment, and crack development of prestressed bridge girders containing SCC and CC. In addition, river gravel and limestone aggregate were used to evaluate the impact of aggregate type on the mechanical properties and bond performance in the full-scale testing of both SCC and CC girders. Early-age characteristics, material properties, and field observations are also documented. Test results indicate that the flexural capacity and bond performance of the SCC girders are similar to those of the companion CC girders. Also, AASHTO equations for the nominal moment were found to be appropriate for SCC girder-deck systems similar to those tested in this study. The AASHTO expressions used were found to be appropriate for estimating the cracking moment for the river gravel SCC girder-deck system, but they slightly overestimated the cracking moment for the limestone SCC girder-deck system.