桩锚支护深基坑开挖对近邻管线变形影响分析

ANALYSIS OF THE INFLUENCE OF PILE-ANCHOR SUPPORTING DEEP FOUNDATION PIT EXCAVATION ON ADJACENT PIPELINES

以北京市某深基坑项目为背景,应用有限元软件ABAQUS建立了围护结构-管线-土体三者耦合的三维有限元计算模型,模拟分析了管线与基坑距离、管线埋深、管线材料性质等因素对基坑周边地下管线沉降变形的影响。分析表明管线整体沉降曲线呈现“两边小、中间大”的抛物线形状,基坑角部空间效应对管线沉降变形的控制效果显著;随着地下管线与基坑距离的增加,管线端部与中部的沉降差值及管线的最大沉降位移均表现为先增大后减小;随着地下管线埋深的增加,管线端部与中部的沉降差值及管线的最大沉降位移均表现为先增大后减小再增大;不同材质管线的沉降变形表现为,钢管<铸铁管<混凝土管<pvc管。

Based on a deep foundation pit project in Beijing,a three-dimensional finite element calculation model of envelope-pipeline-soil was established by using finite element software ABAQUS.Furthermore,the model simulates and analyzes the influences of the distance between pipeline and foundation pit,the buried depth of pipeline,the properties of pipeline materials,and other factors on the settlement deformation of underground pipelines around the foundation pit.The results shows that the overall settlement curve of the pipeline shows a parabolic shape of small value on both sides and large value in the middle.Moreover,the corner space effect of the foundation pit has a significant control effect on the settlement deformation of the pipeline;With the increase of the distance between the underground pipeline and the foundation pit,the settlement difference between the end and the middle of the pipeline and the maximum settlement value of the pipeline both increased first and then decreased;With the increase of the buried depth of the pipeline,the settlement difference between the end and the middle of the pipeline and the maximum settlement value of the pipeline both increased initially,followed by an decrease,but then again increased.Finally,the settlement deformation of pipelines of different materials is as follows,steel pipe<cast iron pipe<concrete pipe<PVC pipe.