泥石流作用下桥墩的动力响应分析

Dynamic Response Analysis of Bridge Pier under the Action of Mudslides

由于部分山区桥梁跨越发育冲沟,会受到泥石流的冲击作用,基于桥梁构件能力保护原则,对泥石流作用下桥梁动力响应分析的研究就显得尤为重要。应用有限元动态接触方法对碰撞过程进行数值模拟,选取某高速公路30 m实心T墩建立三维实体有限元模型,分析其在泥石流作用下的动力响应情况。研究表明,在泥石流冲击作用下,块石与桥墩接触区及下部构件连接处应力较大,墩顶位移随上部荷载压力增大而不断减小,即设计应考虑分别提高桥墩的承载能力及其构件连接处的变形能力。

A bridge across the developed gully is likely to be affected by the impact of mudslides. Based on the requirement for bridge structures to be capable of being protected,the analysis of dynamic response of bridges under the action of mudslides is particularly important. This paper uses the finite element dynamic contact method to simulate numerically the collision process,and selects a class Ⅰhighway with 30 m T pier in Yunnan province to establish a three-dimensional solid finite element model to analyze its dynamic response under the action of mudslides. Research results show that under the impact of mudslides,stone and pier contact region and the lower member joints are exposed to larger stress,and the pier top displacement increases with the decrease of upper load pressure continuously.Thus,the bearing capacity of the bridge pier and the deformation ability of its member elements need to be improved.