浅析深基坑分坑开挖对临近地铁附属结构的影响

以上海漕河泾开发区赵巷园区二期深基坑支护实例为背景,分析了邻近地铁深基坑工程的实际应用特点,介绍了基坑围护设计方案选型、分坑平面布置,以及考虑临近地铁的保护措施,基于有限元数值模拟归纳,分析了分坑的空间平面尺寸对临近地铁附属结构变形的影响,并通过有限元分析结果与基坑实际设计方案进行对比。结果表明,控制临近地铁基坑的分坑宽度在2倍的基坑挖深左右,可以有效控制基坑开挖对邻近建筑的变形速率和总变形影响。

Brief Analysis on Influence of Deep Foundation Pit Excavation by Pit on Auxiliary Structure Adjacent to Subway

Based on the example of deep foundation pit supporting in Zhaoxiang Park Phase II of Shanghai Caohejing Development Zone, the practical application characteristics of a deep foundation pit project adjacent to subway are analyzed, the selection of the design scheme of the foundation pit enclosure and the plane layout by pit are introduced, and the protection measures adjacent to subway are considered. Based on the finite element numerical simulation, the influence of the spatial plane size by pit on the deformation of the auxiliary structure adjacent to subway is analyzed. The results of finite element analysis are compared with the actual design scheme of foundation pit. The results show that the influences of foundation pit excavation on the deformation rate and total deformation of adjacent buildings can be effectively controlled by controlling the by-pit width of the foundation pit adjacent to subway at about twice the depth of the foundation pit excavation.