基坑装配式可回收支护和桩锚支护结构的受力与变形分析

Stress and Deformation Analysis of Assembled Recoverable Support and Pile Anchor Support Structure in Foundation Pit

基坑支护工程在我国城市化建设过程中具有重要的作用,一些新型支护形式的出现极大丰富了基坑支护的多样性。本文以衡水市现场基坑支护实验工程为背景,工程将装配式可回收支护结构和桩锚支护结构作为研究对象,通过室内土工试验数据确定本构模型参数,利用有限元软件PLAXIS3D建立三维有限元模型,模拟基坑开挖和支护的全过程,并分析基坑土体和支护结构的受力、变形特征。对比相同土体和开挖条件下装配式可回收支护结构和桩锚支护结构的稳定性,结果表明:装配式可回收深基坑支护形式能更好地控制土体隆起变形,更利于限制深层土体的位移,也可以更好地控制坑顶水平位移。装配式支护结构施工简单速度快,且能回收利用,符合我国绿色建筑理念。

Foundation pit support engineering plays an important role in the process of urbanization in China. The emergence of some new support forms has greatly enriched the diversity of foundation pit support. In this paper, by taking the Hengshui field foundation pit support experiment project as the background, the prefabricated recyclable support structure and pile-anchor support structure are studied;By using the finite element software PLAXIS3 D, the constitutive model parameters are determined through indoor geotechnical test data, and the three-dimensional finite element model is established. Further, the process of foundation pit excavation and support is simulated, and the stress and deformation of foundation pit soil and support structure characteristics are analyzed. Through comparing the stability of the assembled recyclable support structure and the pile-anchor support structure under the same soil and excavation conditions, the following conclusions are obtained: The assembled recyclable deep foundation pit support form can not only better control the soil uplift deformation, which is more conducive to limit the displacement of deep soil, but also can better control the horizontal displacement of the pit top. The fabricated support structure is simple, quick in construction, recyclable, and conforms to the concept of green building in China.