基于时空效应的深基坑工程变形规律分析

以基坑开挖的"时空效应"为根据,对上海市陶家宅深基坑工程的监测数据进行统计分析。对各监测项目在不同施工阶段、不同空间位置的变形规律进行讨论,重点分析了基坑自身变形及周边环境的变形在不同"时空条件"下的表现形式与内在联系。结果表明:各监测项目的变形主要发生在基坑开挖阶段,底板可以有效地控制基坑自身和周围环境的变形;基坑的空间效应影响程度沿远离坑角方向衰减,且基坑长深比越大,空间效应表现得越明显;围护结构最大侧移及最大侧移出现的深度均随开挖深度的增大而增大;基坑周边地表沉降沿远离坑壁方向呈现先增大后减小的三角形变化趋势;基坑周边地表沉降与管线沉降规律大体相同,但在数值上存在一定的差别。

Analysis of Deformation Law of Deep Foundation Pit Based on Space-time Effect

Based on the "space-time effect" of foundation pit excavation, the monitoring data of Taojiazhai deep foundation pit project in Shanghai are analyzed. The deformation laws of various monitoring projects at different construction stages and different spatial locations are discussed, and the manifestations and internal relations of the deformation of the foundation pit itself and the surrounding environment under different "space-time conditions" are emphatically analyzed. The results show that the deformation of each monitoring project mainly occurs in the excavation stage of the foundation pit, and the baseplate can effectively control the deformation of the foundation pit itself and the surrounding environment; the spatial effect of the foundation pit decreases along the direction away from the pit angle, and the larger the ratio of length to depth of the foundation pit, the less obvious the spatial effect is;the maximum lateral displacement and the depth of maximum lateral displacement of retaining structure increase with the increase of excavation depth; the surface settlement around the foundation pit increases first and then decreases along the direction away from the pit wall; the surface settlement around the foundation pit is basically the same as that around the pipeline, but there are some differences.