软土地区56m深圆形基坑的优化设计与实践  

Optimal design and practice of a 56m ultra-deep circular excavation in soft soils

作　　者：王卫东 徐中华[2] 宗露丹 朱雁飞 翁其平[2] WANG Weidong;XU Zhonghua;ZONG Ludan;ZHU Yanfei;WENG Qiping(East China Construction Group Co.,Ltd.,Shanghai 200011,China;East China Architecture Design&Research Institute Co.,Ltd.,Shanghai 200002,China;Shanghai Tunnel Engineering Construction Co.,Ltd.,Shanghai 200002,China)

机构地区：[1]华东建筑集团股份有限公司,上海200011 [2]华东建筑设计研究院有限公司,上海200002 [3]上海隧道工程有限公司,上海200002

出　　处：《建筑结构》2022年第10期1-10,共10页Building Structure

基　　金：上海市科学技术委员会科研计划项目(No.13231201006)。

摘　　要：上海苏州河段深层排水调蓄管道系统工程中的苗圃竖井基坑直径30m,挖深56.3m,为软土地区超深圆形基坑工程。由于原设计逆作内衬墙方案多达15个施工工况,施工组织难度大,提出了竖向设置5道环梁的顺作优化方案。基坑开挖前采用三维m法,考虑土与结构共同作用的三维有限元法分别对优化方案和原设计方案进行了模拟分析。结果表明:优化方案的地下连续墙满足承载力要求,验证了优化方案的可行性。采用优化方案实施的苗圃竖井基坑实测数据与计算结果规律基本一致;地下连续墙侧向变形很小,对周边建(构)筑物影响也很小;地下连续墙表现出以环向轴压为主、竖向受弯为辅的受力性态。苗圃竖井基坑采用顺作优化方案,实施顺利并取得了良好的技术经济效果,为软土地区类似超深圆形基坑工程设计和施工提供了借鉴。The diameter and excavation depth of the Miaopu shaft circular excavation of the deep tunnel sewerage project of Suzhou River in Shanghai were 30 m and 56.3 m, respectively, which was a ultra-deep circular excavation project in soft soils. In original design, the shaft would be excavated in 15 steps using top-down method. This would bring great difficulties to construction organization. Therefore, an optimized bottom-up construction scheme with 5 ring beams was proposed. Three dimensional beam-spring model method and three dimensional finite element method considering the interaction of soils and structures were used to simulate and analyze the original and the optimized construction scheme of the deep excavation. The results show that the diaphragm wall could sustain the lateral pressure during excavation using the optimized bottom-up construction scheme. Monitoring results showed that deformation of the circular diaphragm wall and the adjacent facilities were very small. The diaphragm wall was mainly subjected to circumferential axial compression and supplemented by vertical bending. These monitoring results were consistent with the calculation results. Good technical and economic results have been achieved using the optimized bottom-up construction scheme and this provides a reference for the design and construction of similar ultra-deep circular excavation in soft soil area.

关 键 词：超深圆形基坑 软土 三维分析 优化方案 变形性状 

分 类 号：TU318.1[建筑科学—结构工程]