双排桩支护结构变形特点与土压力有限元分析

论述了双排桩支护结构设计的基奉理论、简化模型及内力计算方法；运用有限元建立平面应变模型分析双排桩支护结构，对双排桩支护结构所受土压力取值进行了分析与修正。研究表明，双排桩具有较大的侧向刚度，可有效限制围护结构的侧向变形，应将桩顶与连梁做成刚性连接，以保证有效发挥双排桩的支护效果。基坑开挖面以上桩身所受主动土压力与理论主动土压力值相近，开挖面以下桩身所受土压力介于理论主动土压力与静止土压力之间，并随着深度的增加，愈来愈接近静止土压力值。前、后排桩所受的被动土压力与理论被动土压力值相差较大，后排桩被动土压力值接近静止土压力。

Analyses on Stressed Deformation and Earth Pressure of Double-row Pile Retaining Structure

A fundamental theory,simple model and stress analysis method for the double-line pile retaining structure design was introduced.The finite element process ANSYS was compiled to set up the model of double-row pile retaining.The deformation and earth pressure of the structure was analyzed.Some reliable conclusions for engineering are obtained.With the effective co-operation of double-line piles and soil,the double-line piles retaining structure can confine side direction deformation effectively,the double-line pile retaining structure has strong lateral rigidity;The active earth pressure of pile above excavated surface is very close to the theoretical value,and the active earth pressure of pile below excavated surface is between the theoretical and static value;the passive earth pressure of both row piles are very different from theoretical passive earth pressure value,and passive earth pressure of back row piles is near to static value.