基坑周边建筑物不均匀沉降变形的模拟分析

为解决基坑工程对周围建筑物产生影响的问题,应用弹塑性大变形理论对桩-锚支护形式下基坑开挖引起的周边建筑物不均匀沉降问题进行了模拟分析.分别研究了建筑物距基坑8.5、17.0、25.5和34.0 m时,锚杆层数、开挖深度等因素对周边建筑物不均匀沉降变形的影响.研究表明:当建筑物与基坑的距离小于1.5H(H为基坑开挖深度)时,建筑物的不均匀沉降变形受锚杆层数的影响较大,并随锚杆层数的增加而减小,当建筑物与基坑的距离大于1.5H时,建筑物的不均匀沉降变形受锚杆层数的影响不大;一般地,建筑物的不均匀沉降变形随基坑开挖深度的增加呈现正-负-正的变化趋势,即出现了倾斜方向的变化;当基坑开挖深度大于临界开挖深度时,建筑物的不均匀沉降变形显著增大.

Numerical analysis of differential sedimentation deformation of building around foundation pit

In order to reduce the effect of foundation pit on the nearby building,the paper introduces the application of elastic-plasticity large deformation theory to analyze the differential sedimentation deformation of nearby building created by excavation of foundation pit under the support form of pile-anchor and discusses some rules of differential sedimentation deformation of nearby building affected by anchor layer and excavation depth when the distance between building and foundation pit is 8.5,17.0,25.5 and 34.0.The research shows that when the distance between building and foundation pit is smaller than 1.5H(H expresses the excavation depth of foundation pit),the differential sedimentation deformation of building is affected by anchor layer largely,and decreases with the increase of anchor layer,and when the distance between building and foundation pit is more than 1.5H,the sedimentation deformation of building is affected by anchor layer little;generally,the differential sedimentation deformation of building presents changing tendency of positive-minus-positive with the increase of excavation depth,namely the incline direction changed;when the excavation depth overruns the critical excavation depth,the differential sedimentation deformation of building increases observably.