承压泉域富水地层地铁站基坑开挖扰动变形规律分析  

Analysis of Disturbance-Induced Deformation During Excavation of a SubwayStation Foundation Pit in a Water-Rich Stratum within a Confined Spring Zone

作　　者：尚天丽 李玉祥 韩玉龙 赵伟伟 管景澄 朱尚明 Shang Tianli;Li Yuxiang;Han Yulong;Zhao Weiwei;Guan Jingcheng;Zhu Shangming(Sinohydro Bureau 4 Co.,Ltd.;PowerChina Railway Construction Investment Group Co.,Ltd.)

机构地区：[1]中国水利水电第四工程局有限公司,西宁市810006 [2]中电建铁路建设投资集团有限公司,北京市100071

出　　处：《勘察科学技术》2025年第2期42-47,共6页Site Investigation Science and Technology

摘　　要：为探究承压泉域富水地层中地铁车站基坑开挖过程中的扰动变形规律,该文依托在建济南地铁开源路站,通过分析现场监测数据与建立考虑降水的三维有限元模型,探究基坑降水与基坑开挖所导致的基坑外地表与管线变形、基坑内竖向变形与围护墙的水平变形规律。分析发现基坑开挖时坑外地表最大沉降值发生在1.0~1.5倍基坑深度范围,随着基坑开挖,坑外地表沉降逐渐增大,在开挖完成后的一段时间内会有一回弹,之后又持续沉降;地连墙水平位移不断增大,且最大值逐渐下移;基坑外直径较大的管线受基坑开挖扰动影响较大,基坑开挖时沉降不断增大;对于富水地层中开挖的车站基坑,降水变形对土体变形影响较大,因此当基坑内部进行降水时,应当采取坑外回灌等措施以减小地表变形。To investigate the disturbance-induced deformation characteristics caused by excavation in water-rich strata within a confined spring zone,this paper analyzes site monitoring data and establishes a three-dimensional finite element model incorporating dewatering effects,using the under-construction Kaiyuan Road Station of the Jinan Subway as a case study.The research examines surface and pipeline deformations outside the pit,as well as vertical deformation and the horizontal displacement of the retaining wall within the pit induced by both dewatering and excavation.The analysis reveals that the maximum surface settlement outside the pit occurs at 1.0-1.5 times the excavation depth.As excavation progresses,surface settlement outside the pit increases,followed by a temporary rebound after excavation is completed,before continuing to settle over time.The horizontal displacement of the diaphragm wall increases continuously,with the zone of maximum displacement gradually shifting downward.Pipelines with larger diameters outside the pit experience more pronounced settlement due to excavation-induced disturbances.For foundation pits excavated in water-rich stratum,dewatering-induced deformation has a considerable impact on soil movement.Therefore,when dewatering inside the pit,measures such as external recharge should be implemented to mitigate surface deformation.

关 键 词：基坑开挖 扰动变形 富水地层 降水变形 

分 类 号：U231.3[交通运输工程—道路与铁道工程]