相邻基坑围护结构变形及控制的模拟与实测  

Simulation and measurement on the deformation and control effect of adjacent foundation pit excavations

作　　者：胡敏云[1] 夏佳莉 寿树德 袁静[2] 张勇[1] HU Minyun;XIA Jiali;SHOU Shude;YUAN Jing;ZHANG Yong(Institute of Geotechnical Engineering,Zhejiang University of Technology,Hangzhou 310023,China;Zhejiang Architectural Design and Research Institute Co.,Ltd.,Hangzhou 310027,China)

机构地区：[1]浙江工业大学交通岩土工程研究所,浙江杭州310023 [2]浙江省建筑设计研究院,浙江杭州310027

出　　处：《浙江工业大学学报》2023年第5期497-503,552,共8页Journal of Zhejiang University of Technology

基　　金：国家自然科学基金面上项目(51878616)。

摘　　要：通过对杭州市深厚软土地区的相邻基坑群开挖过程进行全工况数值模拟,评估基坑设计中采用的各项工程措施对抑制相邻基坑施工相互影响的效果,并结合工程实测数据分析,探究已开挖基坑的围护结构受邻近后开挖基坑影响的变形发展规律。分析表明:相邻基坑先后施工时引起已建基坑土体位移模式改变,导致支撑轴力减小、地表沉降加剧、相邻侧坑底隆起减小,且基坑相邻侧围护结构侧移发展方向发生转变,出现向坑外的“回弹”;软土基坑采用带内支撑的挡墙式支护结构对相邻基坑施工较为敏感,可以采用设置板带支撑和对坑底土体进行加固等方式消减基坑受邻近施工影响而产生的附加变形。Through a numerical simulation of the full excavation process of adjacent pit groups in a deep soft soil area in Hangzhou,China,the validity of the engineering measures adopted in the pit design to mitigate the mutual influence of neighbor pits during construction is evaluated.The deformation reaction of the retaining structure of the excavated pits to the adjacent post-excavation is analyzed by the engineering measured data.It is shown that adjacent pit excavation causes a change in the displacement pattern of the soil outside the built-pit,resulting in a reduction in the axis force of struts,an increase in the surface settlement of soil in between,a reduction in the heave of the pit bottom along the adjacent side,and a change in the direction of the lateral displacement of the retaining wall on the adjacent side of the pit,known as outside“rebound”.Soft soil pits retained by the strutted wall are known to be sensitive to the adjacent pit construction.Plate-strut substitution and bottom reinforcement are suggested in designing a pit retaining structure to reduce the additional deformation of the pit caused by adjacent excavation disturbance.

关 键 词：软土 相邻基坑施工顺序 变形控制 有限元分析 工程监测 

分 类 号：TU91[建筑科学—建筑理论]