基于PLAXIS深基坑支护设计仿真数值分析

Numerical Simulation on Design of Deep Foundation Pit Support Based on PLAXIS

采用PLAXIS大型有限元计算程序,对成都某高楼深基坑分步开挖过程中支护结构的变形、受力及周边地表的沉降进行了有限元分析,得出了分步开挖各个阶段围护桩的变形、预应力锚索的锚固力及周边地表沉降的变化规律。结果表明:有限元计算结果与监测数据较为吻合;有限元分析能较好地预测基坑开挖过程中支护结构的变形规律和周边地表沉降的分布规律。

Using PLAXIS, a large FEM program, this paper conducted finite element analysis in relation to the deformation and stress of the supporting structure during the excavation in steps of deep foundation pit for a building in Chengdu, and also to the ground settlement surrounded. The established finite element model simulated the actual processes of excavation and supporting, through which the change laws of the deformation of fender piles, the anchoring force of prestressed cable and the ground settlement surrounded during each phase of the excavation in steps were obtained. The results show that the calculation result from FEM agrees with the monitoring data, thus finite element analysis could predict both the deformation law of supporting structure and the distribution law of ground settlement surrounded during excavation of foundation pit.