软土深基坑双排桩支护结构的影响因素分析

Factors Affecting Double-row Piles in Deep Soft Soil Foundation

基于软土地区的某深基坑双排桩支护工程，采用有限单元法建立了三维仿真计算模型对双排桩的受力和位移特性进行计算，系统分析了双排桩排间距、桩径以及前后排桩长等影响因素对双排桩支护结构受力和位移的影响，得到该软土基坑工程双排桩支护结构的最佳排间距、桩径和桩长。结果表明：当双排桩桩径取0．8～1．0 m、排间距取桩径的3～4倍时，排桩的弯矩分布和桩身的位移比较合理，可以最大化地发挥双排桩的支护作用；相比于后排桩桩长，增加前排桩的桩长对提高支护结构的稳定性更有效。

A 3D finite element model was established to calculate the forces and displacements of the double-row pile retaining structure of a foundation pit in soft soil area.The influences of row distance,pile diameter and pile length on the force and displacement of the structure are analysed in order to get the optimal pile row spacing,pile diameter and pile length.Results show that the distribution of bending moment and the displacement of pile are rea-sonable when the pile diameter is 0.8m-1 .0m and the row distance is 3 to 4 times the pile diameter.Increasing the length of front pile is more effective to improving the stability of the retaining structure than increasing the length of back pile.