基于弹塑性平面应变有限元方法，分析了某大型深基坑开挖过程中临近管线的位移变化规律。基于Abaqus软件，引入莫尔-库伦为屈服准则的本构模型，采用平面应变四节点单元形式，利用单元生死功能模拟基坑开挖全过程，以计算基坑开挖过程中周边煤气管、配水管位移变动情况，并和实时监测数据进行对比，得出计算值与监测值的规律一致，验证了计算方法的合理性。在此基础上，分别分析了内支撑、桩体刚度以及表面堆载对管线位移的影响规律。研究结果表明：内支撑对控制基坑周边管线位移起着极其关键的作用；随着桩体刚度的增大，管线沉降会逐渐减小；表面堆载的增大，则会导致管线位移的增大，但是后两个因素的影响相对不显著。%Base on the elasto-plastic plane strain finite element method,displacements laws of the adjacent pipeline caused by a deep foundation pit excavation are analyzed. The Abaqus software is adopted,Mohr-Coulomb constitutive model and CPE4 element type are introduced. The function of model changing and removing is applied to simulate the displacements laws of gas pipeline and water distribution pipeline during the whole excavation process. Then the computation results are compared with the real-time monitoring data. The results show that the calculated values are close to the monitoring values. Furthermore,the influence rules of the support styles,pile stiffness,surface load for displacements of the pipelines are analyzed respectively. It is shown that the support plays a critical role in the displacement of foundation pit surrounding pipeline. The settlements of pipeline will gradually decrease with the increasing stiffness of pile,while increase with the increasing surface load. But the last two factors are not as remarkable as the first factor.
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