动荷载作用下软土地区基坑开挖周围土体位移研究

Research on displacement of soil around foundation pit under dynamic load in soft Clay Area

软土地区深大基坑开挖对周围土体及构筑物的位移有重要影响。以昆明市某软土区圆形基坑工程为背景,通过分析基坑支护结构、周围土体和动荷载作用下构筑物的位移监测数据,系统研究基坑开挖过程中位移变化的时空效应。结果表明:地表土体位移随着与基坑的横向距离不断增加而减小且基坑开挖对地表土体沉降量的影响范围大于对水平位移的影响范围;当有动荷载作用于软土区基坑周围构筑物时,基坑开挖对构筑物的位移有相对较大的影响;在基坑周围一定范围内,同一点处的水平位移和沉降量的变化具有相关性;基坑周围土体水平位移随深度增加而减小并逐渐趋于0。研究成果拟为类似工程提供借鉴。

The excavation of deep and large foundation pit in soft clay area has important influence on the displacement of surrounding soil and structure.Taking the foundation pit in Kunming as an engineering background,by analyzing the displacement monitoring data of the foundation pit supporting structure,the surrounding soil and the structures under dynamic load,the spatio-temporal effect of the displacement during the excavation of the foundation pit is studied systematically in this paper.The results show that the displacement of the surface soil decreases with the increase of the lateral distance from the foundation pit and the influence of excavation on surface soil settlement is greater than on horizontal displacement.When the dynamic load acts on the surrounding structures of the foundation pit in the soft soil area,the excavation has a relatively larger influence on the displacement of the structure.There is a correlation between horizontal displacement and settlement at the same point within a certain area around the foundation pit.With the increase of depth,the horizontal displacement of the soil around the foundation pit decreases gradually and tends to 0.The research results can provide reference for similar engineering.