摘要
为探究管廊深基坑对周围环境的影响,基于Midas GTS NX有限元软件,结合综合管廊基坑工程实例,建立分步降水开挖和一次性降水开挖工况下的数值模型,研究不同工况下基坑降水开挖对周边环境的影响,对渗流场、基坑周边地表沉降和既有构筑物的变形进行分析。结果表明:分步降水较一次性降水方式,土层渗流速度明显下降;基坑周边地表沉降近似呈“勺形”分布,沉降值符合变形要求;既有地铁隧道靠近基坑一侧水平位移和顶部竖向位移较大,且竖向位移总体大于水平位移;分步降水工况下基坑降水开挖对周边环境影响较一次性降水小,建议在进行基坑降水开挖时,尽量选择分步降水,以减少对周边环境的影响,可对类似工程提供参考。
To investigate the impact of deep foundation pits for pipe galleries on the surrounding environment,based on the Midas GTS NX finite element program,combined with a comprehensive pipe gallery foundation pit engineering example,the numerical model under the condition of step precipitation excavation and one-time precipitation excavation is established,and the influence of foundation pit precipitation excavation on the surrounding environment under different working conditions is studied,the sewerage field,the surface settlement around the foundation pit and the deformation of the existing subway tunnel are analyzed.The results show that compared to one-time water application,the infiltration rate of soil exhibits a significant decreasing trend under stepwise water application;The ground settlement around the approximate distribution is"spoon",settlement values conform to the requirements of the deformation;Near the existing subway tunnel excavation side top horizontal displacement and vertical settlement deformation,overall is greater than the horizontal displacement and vertical settlement;Under the condition of step-by-step precipitation,the impact of foundation pit precipitation excavation on the surrounding environment is smaller than that of one-time precipitation.it is recommended to choose step-by-step precipitation when conducting foundation pit precipitation excavation,so as to reduce the impact on the surrounding environment.
作者
贺晓
郑会桓
HE Xiao;ZHENG Huihuan(Beijing Jingtou Urban Utility Tunnel Investment Co.,Ltd.,Beijing 100027,China)
出处
《粉煤灰综合利用》
2025年第2期74-78,123,共6页
Fly Ash Comprehensive Utilization
关键词
基坑降水
降水工况
渗流场
周边沉降
地铁隧道变形
foundation pit precipitation
precipitation conditions
seepage field
peripheral settlement
deformation of subway tunnels
