深基坑开挖的有限元模拟与分析

摘要

针对密集建筑群中的深基坑开挖工程,将基坑、支护结构及周边建筑物放在一个系统中进行研究.运用大型工程软件 ABAQUS 对天津地区典型工程地质条件下,典型深基坑工程环境中,深基坑开挖的全过程进行了数值模拟分析,得到了一些对深基坑工程设计和施工有工程实际意义的结论.%Urban deep foundation pits are generally surrounded with dense buildings, this paper put deep foundation pits bracing structures and adjacent structures in an integrate system to study. Under the typical geological conditions of Tianjin area, using ABAQUS to simulate and analyze the construction process of the deep foundation pit. The conclusions are valuable for foundation pits engineering design.Key words: deep foundation pit; adjacent structure; numerical simulation; settlement TEST STUDY AND STABILITY ANALYSIS OF THE GEOGRID-REINFORCED AND PILE-SUPPORTED COMPOSITE FOUNDATIONAbstract:The study of the regulation of foundation' s settlement、 the change in stress of piles and soil and the reinforced stills to the influence on the stability of geogrid-reinforced and pile-supported composite foundation are probed through an indoor model test of geogrid-reinforced and pile-supported composite foundation with extremely flexible load. The test results show that as the thickness of the still increases, the settlement of the composite foundation increases obviously and the shaft settlement, pure sand settlement increase, it is not conducive to the stability of composite foundation. The composite foundation of thick stills can be greatly improved by adding the number of geo-grids and the settlement except the shaft settlement will decrease and the stress ratio of the pile to the soil will increase, in favor to the overall stability of the foundation.