Nonlinear Dynamic Response and Assessment of Bridges under Barge Impact with Scour Depth Effects

Abstract

The lateral impact of barges is a vital load case for river-crossing bridges. In addition, flood-induced scour has been recognized as a leading cause of bridge failure. However, current bridge performance assessment often takes the original bridge configuration as the basis for analyzing such impact without considering the effects of scour depth. In this paper, high-resolution finite-element (FE) based modeling is conducted to investigate barge impact on the nonlinear response of a pile-supported bridge with variable scour depths. The significant findings are multifold. First, it is favorable to find that the peak impact force and the crush deformation in the bow of the barge generally do not change significantly as scour depth varies. However, it is cautious to note that the peak displacement at the pier and the local deformation in the piles significantly increases as scour depth increases. It is stated that these findings and the method in this paper can assist in the quantitative assessment of the performance of river-crossing bridges in service and may provide information for the development of the next-generation bridge design specifications regarding barge impact.