The main feature of annular support system is annular girder pressed, thus a reasonable support system can give full play to concrete material performance among internal support systems. The annular support can optimize number of support and upright col⁃umn, make the support system provided with obvious benefit of easy to excavate earthwork, all right major structure construction space, less support removal amount and shorter construction period. But annular support system has more complex stress condition;especially the planar double annular girders support, to design and construction the support all have higher requirements. Land use around the foundation pit of Rongli Building in Foshan is on the edge, the foundation pit is large scale and hard to support, after comprehensive comparison, selected planar double annular girders assembled support+supporting piles support system, with respect to other support schemes, it has obvious economic benefit. Based on project situations, geologic and hydrologic conditions and foundation pit support scheme design and demonstration, through 3D finite element and Lizheng software integral calculation, simulated and analyzed the foundation pit stress state. Combined with foundation pit construction process and actual monitoring data, comparatively analyzed and studied annular support system stress characteristics. The studied result not only enriched soft soil area large complex foundation pit us⁃ing double annular support means related theoretical content, but also provided certain reference for foundation pit support pattern put into practice under similar conditions.%环形支撑体系以环撑受压为主要特点，是内支撑体系中能充分发挥混凝土材料性能的合理支撑体系。环形支撑能优化支撑和竖向立柱数量，使支护体系具有土方开挖方便、主体结构施工空间良好、支撑拆除量少和施工周期短等显著效益。但是环形支撑体系受力复杂，尤其是平面双环支撑，对设计和施工都有较高要求。佛山融利大厦基坑周边用地紧张、基坑规模较大、支护难度大，经综合比选选取平面双环组合支撑+支护桩支护体系，相对于其它支护方案具有明显的经济效益。在对该工程概况、地质水文条件以及基坑支护方案设计论述的基础上，采用三维有限元和理正杆件整体计算方法，模拟分析了该基坑受力状况；结合基坑施工步骤及土方开挖过程中实际监测数据，对比分析与研究了环撑支撑体系的受力特征。研究结果不仅补充了软土地区大型复杂基坑采用双环支撑方式相关的理论内容，而且为今后类似条件下基坑支护方式的实施提供一定参考。
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