坡顶堆载作用下土钉墙变形规律分析

Analysis on deformation law of soil nailing wall under the slope top load

坡顶堆载作用下土钉墙变形规律的研究,可以为采用土钉墙支护形式的基坑工程的施工提供参考。文章以受坡顶堆载作用的某土钉墙支护工程为研究对象,利用Plaxis3D有限元软件进行三维仿真模拟,并结合工程实测数据,分析了坡顶堆载作用下土钉墙的土钉轴力、整体变形以及坡顶变形的相关性。结果表明:基坑坡顶水平位移和沉降之间为非线性关系,且这种关系在正常施工前期并不明显,可近似为线性关系,但是在坡顶堆载作用下非线性关系却非常明显;在坡顶堆载作用下,实施土体开挖等作业会导致土钉墙提前发生破坏,此时的坡顶水平位移临界值仅为开挖深度的5.75‰,应建立多级监测预警机制以保障施工安全。

The study on the deformation law of soil nailing wall under the action of slope top load can provide reference for the construction of foundation pit projects with soil nailing wall support.The article takes an example of a soil nailing wall support project subjected to the slope top load as the research object,and uses Plaxis3D finite element software to carry out three-dimensional simulation.The model starts from the actual project,combines with the actual measured data,and analyzes the soil nailing axial force,overall deformation and the correlation of slope top deformation of the soil nailing wall under the action of slope top load.The results show that there is a nonlinear relationship between the horizontal displacement and settlement of the slope top of the foundation pit.And this relationship is not obvious in the normal pre-construction period,which can be approximated as a linear relationship,but the nonlinear relationship is obvious under the action of slope top load.When excavation and other construction operations are carried out under the action of slope top load,it will lead to early damage of soil nailing wall,and the critical value of horizontal displacement of slope top when damage occurs is only 5.75‰of excavation depth.So a multi-level monitoring and early warning mechanism should be established to guarantee construction safety.