深基坑开挖引起临近深层土体水平变形研究

Study on Horizontal Deformation of Adjacent Deep Soil Caused by Deep Foundation Pit Excavation

深基坑开挖将对周边环境产生较大影响。通过建立三维有限元模型,重点分析了基坑开挖过程中紧邻土体深层水平位移发展规律,并将数值模拟结果与施工现场监测数据进行对比。研究结果表明,邻近土体水平位移对基坑开挖深度较敏感,且随着基坑开挖深度的增大而不断增大,水平位移曲线呈弓形形态,最大水平位移出现在开挖面附近,模拟值约为18 mm,现场监测值约为18.5 mm;围护结构水平位移具有明显的空间效应,基坑长边测点水平位移最大,短边测点次之,坑角最小;数值模拟和监测结果较为接近,变化规律基本一致,证明了设计方案和有限元模型的可靠性。研究结果可为类似工程参考借鉴。

The excavation of deep foundation pit will have a great impact on the surrounding environment.By establishing a three-dimensional finite element model,this paper focuses on the development law of deep horizontal displacement of adjacent soil in the process of foundation pit excavation,and compares the numerical simulation results with the construction site monitoring data.The results show that the horizontal displacement of adjacent soil is sensitive to the excavation depth of the foundation pit,and increases with the excavation depth of the foundation pit.The horizontal displacement curve is in an arched shape.The maximum horizontal displacement occurs near the excavation surface,the simulated value is about 18 mm,and the field monitoring value is about 18.5 mm;the horizontal displacement of the retaining structure has obvious spatial effect.The horizontal displacement of the long side measuring point of the foundation pit is the largest,the short side measuring point is the second,and the pit angle is the smallest.The numerical simulation and monitoring results are rather close,and the change law is basically the same,which proves the reliability of the design scheme and finite element model.The research results can be used as a reference for similar projects.