Analytical and Experimental Evaluation of Repairs to Continuous PC Girder Bridge

Abstract

The Wanjiang Bridge, completed in 1976, is the first continuous prestressed concrete (PC) girder bridge erected using the incremental launching method in China. The bridge consists of prismatic separated dual box girders with an overall length of 136 m (1+40+54+40+1 m). The bridge was hit by a tanker on August 5, 2006, and three supporting brackets near Pier 5 were severely damaged. An attempt was made to repair the bridge to recover its original strength. This study evaluated the effectiveness of the repairs, the postrehabilitation properties, and the strength of the damaged brackets and the bridge using static and dynamic field load tests and finite-element method (FEM) analyses. The results show that the finite-element (FE) model and the load tests provide a comprehensive evaluation of the behavior of the bridge structure. The accuracy and reliability of the FE model was investigated and validated through a field loading test. The field loading test and the computer simulation indicated that the original performance of the Wanjiang Bridge was restored and its strength satisfies the design requirements so that any vehicle with load of less than 30 t would be allowed to cross.