非对称多层基坑支护桩体的沉降变形及稳定性数值模拟  

Numerical Simulation of Settlement Deformation and Stability of Asymmetric Multi-Layers Soldier Piles in Deep Excavation

作　　者：程峰 李庆旺[1] 杨德欢 何辉 杨柏[1] CHENG Feng;LI Qingwang;YANG Dehuan;HE Hui;YANG Bai(School of Architecture and Transportation Engineering,Guilin University of Electronic Technology,Guilin,541004;Guilin Research Institute of Geology for Mineral Resource Engineering Co.Ltd.,Guilin 541004)

机构地区：[1]桂林电子科技大学建筑与交通工程学院,广西桂林541004 [2]桂林矿产地质研究院工程有限公司,广西桂林541004

出　　处：《土工基础》2025年第1期73-77,92,共6页Soil Engineering and Foundation

摘　　要：多层基坑非对称开挖中的沉降和变形大小是影响基坑稳定的重要因素,以某地铁多层非对称开挖基坑支护桩为研究对象,利用PLAXIS 3D有限元软件构建楔形计算单元体,模拟多层非对称基坑开挖过程,分析地表沉降、桩顶沉降、桩身水平位移及临近建筑物沉降等指标变化情况。结果表明:桩身水平位移、地表沉降随基坑开挖深度增加而增加,桩顶沉降呈波动趋势减小,临近既有建筑物沉降随基坑距离减小而增加;基坑变形受上部建筑物影响较大,基坑侧附近土体沉降较远端高约14%,承载建筑物侧面土体水平位移较其他侧面高约11%;现场监测基坑实际变形过程与模拟过程基本一致,仅在阶段开挖施工略有差异,表明桩-撑联合支护方式能够有效抑制基坑变形,使基坑各项变形指标处在可控范围内,研究结果对非对称基坑开挖施工过程中变形监测与安全控制有较好的工程指导作用。The settlement and deformation in the asymmetric excavation of multi-layer deep excavations are important factors affecting the stability of the excavation supporting structures.Numerical simulation of support stability can effectively predict possible problems in the deep excavations.The supporting soldier piles of a subway multi-layer asymmetrical excavation system are analyzed by using the PLAXIS 3D finite element software to construct a wedge-shaped analytical unit.The excavation process of the multi-layer asymmetric excavation is simulated,and the ground settlement,pile top settlement,the horizontal displacement of the soldier pile and the settlement of adjacent buildings and other indicators change are predicted.The deformation monitoring and safety control of the asymmetrical multi-layer excavation are studied.The results show that the horizontal displacement of the pile shaft and the surface settlement increase with the increase of the excavation depth.The settlement of the pile top decreases with the increase of the excavation depth,and the settlement of the adjacent existing buildings decreases with the increase of the distance from the excavation.Numerical simulation results show that the deformation of the excavation is greatly affected by the superstructure,the settlement of the soil near the side of the excavation is about 14%higher than that at the far end,and the horizontal displacement of the soil on the side of the bearing building is about ll%higher than that of the other sides;The comparison results of on-site monitoring and numerical simulation show that the actual deformation process of the excavation is basically consistent with the simulation process,and there is only a slight difference in the stage excavation construction,which shows that the pile-brace joint support method can effectively restrain the deformation of the excavation and make the deformation of the excavation.The index is within the controllable range,and the research results have good engineering guidance for deformation

关 键 词：多层基坑 不对称开挖 楔形计算单元 沉降变形 数值模拟 

分 类 号：TU473[建筑科学—结构工程]