桩-网复合地基承载及变形特性的有限元分析

Finite element analysis of the bearing and settlement performances of pile-net composite foundation

采用ABAQUS有限元软件,通过有限元数值模拟的方法分析了路堤荷载作用下桩-网复合地基中土工合成材料刚度、垫层厚度、桩体模量以及桩间距对复合地基的荷载传递特性、桩-土应力比、路基的表面沉降及侧向位移的影响。总结、分析计算结果,获得了桩-网复合地基承载及变形的一些基本特性,如:增加土工合成材料刚度,可显著地减小桩-土差异沉降和路基侧向位移,并增加桩-土应力比;增加垫层厚度,可明地改善桩-土荷载分担比和桩-土应力比等力学性状。这些结果对桩-网复合地基的设计与施工具有一定的指导意义。

Based on the software of finite element method(ABAQUS),the bearing and settlement performances of pile-net composite foundation under embankment load are analyzed by means of numerical simulation. The influence of the stiffness of the geosynthetics,the thickness of the cushion,the elastic modulus of piles and the pile distance on the load transfer in the composite foundation,the stress ratio of pile and soil,the surface settlement and the lateral displacement of roadbed are analyzed. By analyzing simulating results,some features are found on the bearing and settlement performances of pile-net composite foundation. For example,when the stiffness of the geosynthetics is increased,the differential settlement of pile and soil and the lateral displacement of roadbed are greatly reduced,and the stress ratio of pile and soil is increased;with increasing the thickness of the cushion,some mechanical behaviors such as sharing of load and pile-soil stress ratio are obviously improved. All these are of some significance to design and construction of pile-net composite foundation in the future.