兰州地铁土门墩车站基坑开挖支护有限元分析  

Finite element analysis of foundation pitexcavation and support at Tumendun station of Lanzhou metro

作　　者：周杰 任永忠[2] Zhou Jie;Ren Yongzhong(Gansu Honghao Construction Group Co.,Ltd.,Lanzhou 730050,China;Lanzhou Institute of Technology,Lanzhou 730050,China)

机构地区：[1]甘肃弘昊建设集团有限公司,甘肃兰州730050 [2]兰州工业学院,甘肃兰州730050

出　　处：《山西建筑》2021年第17期57-59,86,共4页Shanxi Architecture

基　　金：甘肃省高等学校创新能力提升项目(2019B-180);甘肃省陇原青年创新创业人才(团队)项目(2020RCXM196)。

摘　　要：近几年地铁深基坑的支护、开挖及与周边环境的相互影响成为关注的热点。以兰州地铁土门墩车站为工程背景,采用岩土工程分析有限元软件Midas对该车站进行了数值模型分析。其结论表明:基坑开挖后,坑底土体由于开挖卸荷等原因发生回弹,且回弹量随开挖深度的加深不断增加;支护桩体的最大位移发生在基坑开挖角部附近,最大位移值出现在基坑开挖深度的1/2处,桩身弯矩的最大值出现在横向支护桩桩深的1.5 m处,且桩身在开挖深度的2/3处附近出现弯矩为零的点;在开挖截面发生变化处横向内撑出现受拉状态。In recent years,the support and excavation of deep foundation pits of subways and their mutual influence with the surrounding environment have become the focus of attention.This paper takes the Lanzhou Metro Tumendun Station as the engineering background,and uses the geotechnical engineering analysis finite element software Midas to carry out a numerical model analysis of the station.The conclusion shows that after the excavation of the foundation pit,and the soil at the bottom of the pit rebounded due to excavation unloading and other reasons,the maximum displacement of the supporting pile occurred in the foundation pit.Near the excavation corner,the maximum displacement value appears at 1/2 of the excavation depth of the foundation pit,the maximum pile bending moment appears at 1.5 m of the lateral support pile depth,and the pile body is at 2/3 of the excavation depth.There are 2/3 of the excavation depth where the bending moment is zero;when the excavation section changes,the lateral internal bracing appears in tension.

关 键 词：地铁 深基坑 支护结构 位移 内力 

分 类 号：TU473.2[建筑科学—结构工程]