大直径环梁支护下深基坑开挖的数值分析

摘要

Deep excavation is bound to cause deformation of supporting structure and surrounding soil, most deep excavation projects are located in downtown area, so the safety of the pit and surrounding environment must be guaranteed. In this paper, a deep excavation example in Tianjin is simulated by ABAQUS. Mohr - Coulomb model is selected. Foundation excavation and support adding are conducted step by step. Interaction between the pile and the soil is also considered. The deformation of supporting structure, surrounding soil and Bottom soil are calculated. The results were compared with field data and deformation regulation of supporting structure and soil is analyzed. Some meaningful conclusions the paper obtain can provide a reference for future similar projects.%深基坑开挖必然会引起支护结构及周围土体的变形，而大多数深基坑工程都位于城市繁华地段，必须保证基坑和周边环境的安全。本文结合天津地区某深基坑工程实例，使用有限元分析软件ABAQUS对该深基坑开挖进行了数值模拟。分析时选用摩尔-库伦土体本构模型，并考虑了深基坑分步开挖，逐级加撑和围护桩与土体的相互作用，计算出了深基坑开挖过程中支护结构的变形、基坑周围土体变形及坑底变形。将数值模拟结果与现场实测数据进行了对比分析，讨论了深基坑开挖过程中支护结构及土体的变形规律。得出一些对深基坑工程设计和施工有实际意义的结论，可为今后类似的工程提供一定的借鉴。