公路穿越既有桥梁的影响研究

Influence on Road Crossing Over Existing Bridge

新建公路穿越既有桥梁,会对桥基产生不利的影响.以苏通大桥为工程背景,通过数值模拟方法研究了新建公路对既有桥基的影响,并对比分析了成层土地基和均质土地基条件下路堤荷载对桥基影响的异同.结果显示,新建公路会对既有桥梁基础产生明显的影响,且随着路堤高度的增大,桥基的变形和内力都随之增大,桩身还会出现负摩阻力;成层土地基条件下桩身最大水平位移出现在最薄弱土层范围内,而均质土地基条件下桩身最大位移出现在桩顶位置.

The newly-built roads of crossing over existing bridges had the adverse effects on the bridge foundation.Taking the Su-tong Bridge as the engineering background,the influence of the newly-built road on the existing bridge foundation was studied by the numerical simulation method.The influence of embankment load on the bridge foundation was analyzed and compared under the condition of layered soil base and homogeneous soil base.The results showed that the new road had a significant impact on the existing bridge foundation.We found when the height of the embankment increased,the deformation and internal force of the piles were increased,and the pile body also had the exhibit negative friction resistance.In the paper,the maximum horizontal displacement of the piles were under the layer which based on the condition occurs within the elevation range of the weakest soil layer,while the maximum displacement of the piles were under the homogeneous soil which based on the condition occurs at the pile top position.