某黄土深基坑变形特性数值模拟分析

Numerical Simulation Analysis of DeformationCharacteristics of a Loess Deep Foundation Pit

为研究某桩锚支护结构黄土深基坑开挖变形规律,考虑深基坑支护结构、初始地应力及土层物理力学参数等因素,采用MIDAS/GTS对其进行数值模拟分析。通过计算,对不同开挖工况下的支护桩桩体水平位移、基坑周边土体沉降、锚索轴力等进行分析。结果表明:基坑各项变形值及锚索轴力值随着开挖深度增加而逐渐增大,其值均在合理范围内,证明此设计可行。但基坑整体变形偏小,设计相对保守,有一定优化空间。通过数值模拟,可以预测基坑开挖变形的情况,为基坑安全施工提供一定保障。

In order to study the excavation deformation law of a loess deep foundation pit with a pile anchor support structure,MIDAS/GTS was used to conduct numerical simulation analysis considering the factors such as the support structure,initial geostress and soil physical and mechanical parameters.Through calculation,the horizontal displacement of the retaining pile,the soil settlement around the foundation pit,the axial force of the anchor cable,and so forth under different excavation conditions were analyzed.The results showed that the deformation values of the foundation pit and the axial force of anchor cable increase gradually with the rise of the excavation depth,and their values are within a reasonable range,which proves that the design is feasible.However,the overall deformation of the foundation pit is relatively small,the design is relatively conservative,and there is some room for optimization.Through numerical simulation,the deformation of foundation pit excavation can be predicted,providing a certain guarantee for the safe construction of the foundation pit.