刚性桩复合地基沉箱挡土结构数值模拟分析

Numerical Simulation Analysis of Caisson Retaining Structure with Rigid Pile Composite Foundation

基于上海市某圈围工程,提出了一种适用于软土地区的刚性桩复合地基沉箱挡土结构,并采用有限元计算软件PLAXIS和小应变硬化土体(HSS)模型对该结构进行了数值模拟分析以论证其安全性。分析结果显示:该结构沉箱最大沉降量、不均匀沉降量及倾斜度均可满足正常使用要求;桩基最大正、负弯矩分别产生在末排、首排桩基,且均满足承载力要求。该结构在受力及变形方面安全可行,为软土地区深水圈围工程提供了一种新的型式。

A caisson structure with rigid pile composite foundation was proposed based on a land reclamation project in Shanghai,which is suitable for soft soil area. The caisson structure was numerically analyzed by finite element analysis software PLAXIS and Hardening Soil Small-Strain（ HSS） model to explore its safety performance. The results show that the maximum settlement,differential settlement and inclination can meet normal use requirements;The maximum positive and negative bending moments of the pile foundation are respectively produced in the last row and the first row of pile foundations,and all satisfy the bearing capacity requirements. The structure is safe and feasible in terms of force and deformation,so can be recommend as a new structural form for the deep water land reclamation project in soft soil area.