某地铁车站深基坑降水开挖对邻近建筑物变形影响分析  

Influence of Dewatering Excavation of Deep Foundation Pit of a Metro Station on the Deformation of Adjacent Buildings

作　　者：谢颖川[1] 杨威 刘长玲[1] XIE Yingchuan;YANG Wei;LIU Changling(School of Urban Construction,Henan Polytechnic Institute,Nanyang 473000,Henan China;The Architectural Design and Research Institute of Henan Province Co.Ltd.,Zhengzhou 450014,China)

机构地区：[1]河南工业职业技术学院城市建设学院,河南南阳473000 [2]河南省建筑设计研究院有限公司,郑州450014

出　　处：《河南科学》2020年第11期1837-1846,共10页Henan Science

基　　金：全国教育科学“十三五”规划2017年度教育部青年课题(EJA170448);河南省高等学校重点科研项目计划(19A560018)。

摘　　要：降水渗流和开挖引起的既有“L”型建筑物变形问题十分复杂,对建筑物正常使用和安全的影响较大.基于大量既有地铁车站工程资料,以兰州某邻近既有建筑物深基坑为研究背景,对基坑邻近建筑物及基坑支护结构变形、基坑内外水位进行现场监测,采用摩尔-库伦弹塑性有限元方法对基坑降水开挖进行了三维应力渗流耦合分析,研究了基坑降水开挖对邻近“L”型建筑物的变形影响.结果表明,在1~4倍开挖深度距离内,基坑降水开挖对“L”型建筑物长边沉降变形影响显著,短边次之,对建筑物水平变形影响最小;在分步降水开挖且降水深度相同时,第二次比第一次对建筑物变形影响大;建筑物处在1~3倍开挖深度范围内时,最大沉降变形发生在长边远离基坑一侧角点附近,最大水平位移发生在远离基坑长短边相交点附近,最大沉降、沉降范围和水平位移均随施工推进向远离基坑方向发展.Deformation of existing“L”type buildings caused by seepage and excavation of precipitation is very complex,which has a serious impact on the operation and safety of buildings.Based on a large number of existing subway station engineering materials,taking a deep foundation pit adjacent to an existing building in Lanzhou as the research background.On-site monitoring of the deformation of the adjacent pit and the foundation pit supporting structure and the water level inside and outside the foundation pit.Three-dimensional stress seepage coupling analysis of foundation pit dewatering excavation by Moore-Coulomb elastoplastic finite element method,and the influence of foundation pit dewatering excavation on the deformation of adjacent“L”type buildings is studied.It is shown that the foundation pit excavation has a significant influence on the long-side settlement deformation of the“L”building in the depth distance of 1-4 times excavation,followed by the short side,which has the least influence on the horizontal deformation of the building.In the case of step-by-step precipitation excavation and the same depth of precipitation,the second time has a greater impact on the deformation of the building than the first time.When the building is within 1-3 times of the excavation depth,the maximum settlement deformation occurs near the corner of the long side away from the foundation pit,and the maximum horizontal displacement occurs near the intersection of the long and short sides of the foundation pit.In general,the maximum settlement,settlement range and horizontal displacement are all developed away from the foundation pit with the construction advancement.

关 键 词：深基坑 分歩降水 邻近建筑物 变形影响 数值分析 

分 类 号：TU473[建筑科学—结构工程]