摘要
以呼和浩特市城市轨道交通二号线学府康都站工程为背景,通过现场监测结果,对地铁基坑开挖过程中的地表沉降、建筑物沉降和管线沉降等进行了系统分析。研究结果表明:地表沉降沿基坑长边方向呈"凹字型"趋势,地表的沉降离基坑边缘越远则沉降值越小;基坑开挖对临近建筑物的变形影响较大;结构楼板的施工会对管线产生向上的位移;底板结构能够有效减少桩顶水平位移,桩底岩性的不同会导致桩顶沉降差异;基坑开挖对墙体最大的影响位置是在基底向上基坑深度四分之一处;墙底水平位移向基坑内偏移和土体卸载所导致的基底土体回弹会引起基底隆起。各测点的最大变形量均小于预警值范围内,没有影响到施工的顺利进展,保证了基坑的稳定性和周边建、构筑物的安全。成果可为呼和浩特市地铁后续工程提供一定的资料参考。
Based on the background of the Xuefu Kangdu station project of the second line of urban rail transit in Hohhot City,through the on-site monitoring results,a systematic analysis of the ground settlement,building settlement and pipeline settlement during the excavation of the subway foundation pit was carried out.The main understandings are as follows:the settlement of the ground surface has a"concave"shape trend along the long side of the foundation pit.The further the settlement of the ground surface is from the edge of the foundation pit,the smaller the settlement value;the excavation of the foundation pit has a greater impact on the deformation of nearby buildings;the construction of the floor slab will cause upward displacement of the pipeline;the bottom plate structure can effectively reduce the horizontal displacement of the pile top,and the difference in the lithology of the pile bottom will cause the difference in the settlement of the pile top;the largest impact of the foundation pit excavation on the wall is in the base upward The depth of the foundation pit is one quarter;the horizontal displacement of the bottom of the wall shifts into the foundation pit and the rebound of the base soil caused by the unloading of the soil body will cause the base swell.The maximum deformation of each measuring point is within the range of the early warning value,which does not affect the smooth progress of the construction,and ensures the stability of the foundation pit and the safety of the surrounding buildings and structures.The results can provide a certain reference for the subsequent project of Hohhot Metro.
作者
何云猋
李洪亮
何彦荣
陈传平
赵鹏
许有俊
张旭
成鹤
HE Yunbiao;LI Hongliang;HE Yanrong;CHEN Chuanping;ZHAO Peng;XU Youjun;ZHANG Xu;CHENG He(China Railway 20th Bureau Group 4th Engineering Co.Ltd.,Shandong 266061,China;School of Civil Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,China)
出处
《建筑结构》
CSCD
北大核心
2021年第S01期1940-1944,共5页
Building Structure
基金
内蒙古自治区自然科学基金项目(2020BS05031)
关键词
盖挖逆作法
地铁车站
现场监测
变形特征
cut-and-cover top-down method
subway station
in-site monitoring
deformation characteristics
