软土深基坑围护结构水平变形特性研究

结合广州某软土深基坑工程实例，建立了地下连续墙、钢筋混凝土内支撑和土层的二维有限元模型，对深基坑开挖过程进行数值模拟.研究结果表明：随着基坑开挖深度的增大,围护结构水平位移增大，最大水平位移的位置由桩顶往下移，而且围护桩水平变形曲线发展形态呈现出向坑内凸的“大肚形”，与实测结果基本一致.支撑结构对减小基坑围护结构的变形起着重要作用，无支撑结构的桩体水平位移最大值达到24.6 mm；土体弹性模量及围护结构刚度对基坑围护结构变形影响较大，桩体水平位移随着土体弹性模量及围护结构刚度的增大而减小.

Research on Deformation Characteristics of Protective Structure of Deep Foundation Pit in Soft Soil

Combined with a project in Guangzhou, the whole model of two-dimensional finite element is established through the diaphragm wall, inner supporting and soil layer. The numerical simulation of deep foundation excavation under the construction process is carried through. Research shows that：With excavation depth increasing, the horizontal displacements of retaining structures increase and the location of the maximum values changes from the top to middle of the retaining structures. The horizontal displacement curves of the retaining structures have a “bow shape”. The monitoring results are compared with the measurement values. The supporting construction plays an important role on the decrease of the horizontal displacement of the pile. The maximum horizontal displacement is 24.6 mm without supporting constructions. And the elasticity modulus of soils has great impact on the foundation displacement. The result can provide valuable references for the design and construction of similar projects.