MJS高压旋喷桩在基坑支护工程中的应用研究

Research on the Application of MJS High-pressure Jet Grouting Pile in Foundation Pit Support Engineering

以南京市中山北路202号地下车库项目基坑支护工程为例,研究不同支护方案下秦淮河漫滩区深基坑开挖过程中支护结构的支护效果。采用ABAQUS有限元分析软件研究MJS高压旋喷桩单排悬臂桩支护、内支撑排桩支护这两种支护方案在施工过程中桩身水平位移、桩后地表沉降、桩身弯矩的变化。结果表明:内支撑排桩支护效果较单排悬壁桩更佳,基坑开挖过程中施加内支撑可以调整桩身受力,有效控制基坑变形;单排悬壁桩支护结构受土体的开挖深度影响较大,一般适用于地质条件较好深度较浅的基坑中。

Taking the foundation pit support project of the underground garage project at No.202 Zhongshan North Road,Nanjing City as an example,the support effect of the supporting structure in the deep foundation pit excavation process of the floodplain area of the Qinhuai River under different support schemes was studied.ABAQUS finite element analysis software was used to study the horizontal displacement of the pile,the surface settlement behind the pile,and the changes of the bending moment of the pile during the construction of the two support schemes of MJS high-pressure jet grouting pile,single row cantilever pile support and inner support row pile support.The results show that the support effect of the inner support row pile is better than that of the single-row overhanging pile,and the internal support can adjust the pile stress and effectively control the deformation of the foundation pit by applying the internal support during the excavation process of the foundation pit.