ABSTRACT
From 2007 to 2019, at least 8 box girder bridges overturned under extreme vehicle load in China. The failure mechanisms and evaluation strategy are important topics to study during these years. In this paper, summarized overturning mechanisms are presented based on forensic diagnose and finite element simulation from the previous studies. Both stability issue and strength issue are introduced and explained for typical accidents. The evaluation strategy is discussed in different aspects including overturning safety calculation, real traffic load monitoring and control system, bridge inspection and examination and structure retrofit. Based on a clearer idea of failure mechanisms, together with combined evaluation strategy, the safety of a box girder bridge under extreme vehicle load can be improved.
