抗滑桩对边坡桥梁桩基受力变形影响分析

当桥梁桩基设置在滑坡上时，常采用抗滑桩作为支挡结构，抗滑桩和桥梁桩基之间存在着相互作用。本文以子-姚高速崖坬沟3号大桥为研究背景，对桥梁桩基及抗滑桩的桩顶位移及桩侧土压力进行监测，分析抗滑桩与桥梁桩基相对位置改变对桥梁桩基受力变形的影响。同时，基于ABAQUS软件分析前后排抗滑桩不同埋置位置下抗滑桩对坡脚桥梁桩基及坡中桥梁桩基的影响。现场监测数据表明抗滑桩与桥梁桩基相对位置对桥梁桩基水平位移及桩侧土压力均有影响，在抗滑桩距离桥基8m和4m时，间距8m加固效果更佳。通过数值模拟，发现后排抗滑桩距离桥梁桩基过远或过近均对桥梁桩基加固效果有限，抗滑桩加固桥梁桩基存在一个最佳距离，对于坡脚桥梁桩基抗滑桩加固最佳距离为3h-5h（h是抗滑桩沿滑坡走向的截面长度），对于坡中桩抗滑桩加固最佳距离为2h-4h，而前排抗滑桩离桥基越近其加固效果越好。如果桥梁桩基在坡体中上部时，桥梁桩基前部土体较多可能会形成牵引式滑坡，需设置前排抗滑桩进行支护，综合考虑确定合理的加固位置。

Influence of anti-slide pile on the stress and deformation of bridge pile foundation on slope

When the bridge pile foundation is set on the landslide, anti-slide pile is often used as the supporting structure of the bridge foundation. At present, the bridge foundation design of landslide section generally does not consider the action of horizontal load, which is usually borne by the design of anti-slide pile. However, there is interaction between the anti-slide pile and bridge pile foundation. The Yawagou #3 birdge at the Ziyao High-speed is taken as the research background, the pile tip displacement and soil pressure of bridge pile are monitored, and the influence of relative position change of anti-slide pile and bridge pile on stress and deformation of bridge pile is analyzed. Based on the field monitoring and numericl simulation, the influence of anti-slide piles at different buried positions of front and rear anti-slide piles on the foundation of bridge at the foot of slope and the foundation of bridge in slope is discussed. The field monitoring data show that the relative position of anti-slide pile and bridge pile foundation has influence on the horizontal displacement of bridge pile foundation and soil pressure of pile side. It is found that, the reinforcement effect is better when the distance between the anti-slide pile bridge foundation is 8 m. The numerical simulation results show that the backrow anti-slide pile has limited effect on the reinforcement of the bridge pile foundation, when the distance between them is too large or small. There is an optimal distance for anti-slide pile reinforcement of the bridge foundation, which is 3-5h for the foundation of the bridge, and 2h-4h for the middle slope. If the anti-slide pile is set in front of the bridge foundation, the its reinforcement effect is better when the distance between them is closer. However, if the bridge pile foundation in the upper slope, the soil in front of the pile may form retrogressive landslide, and the anti-slide file is requred at lower part of the slope and the reinforcement location is dertemined through thorough consideration.