兰州某深基坑开挖支护数值模拟分析  

Numerical simulation analysis of excavation and support of deep foundation pit in Lanzhou

作　　者：李世忠 高立飞 温鹏 任永忠[2] Li Shizhong;Gao Lifei;Wen Peng;Ren Yongzhong(Gansu Jiantou Civil Engineering Construction Group Co.,Ltd.,Lanzhou 730070,China;Lanzhou Institute of Technology,Lanzhou 730050,China)

机构地区：[1]甘肃建投土木工程建设集团有限责任公司,甘肃兰州730070 [2]兰州工业学院,甘肃兰州730050

出　　处：《山西建筑》2022年第20期74-78,共5页Shanxi Architecture

基　　金：横向课题:“基于渗流固结理论的深基坑支护结构性能及选型分析”;兰州工业学院“启智”人才培养计划基金(2019QZ-05);兰州工业学院校级岩土工程重点学科(2019XK-04)。

摘　　要：深基坑的开挖与支护一直是研究的热点,主要是因为深基坑工程逐步向密集型扩展,基坑周边环境的复杂性和区域性也随之增加。以兰州某深基坑工程为研究背景,采用PLAXIS 2D对该基坑工程进行了数值分析。其结论表明:上部土钉墙、下部桩锚支护结构体系在开挖支护过程中,在两种不同的支护体系开挖过渡过程中整体位移发展速率有所减小;嵌固段深度对支护桩的水平位移有较大影响,建议嵌固段至少进入卵石地层的深度为嵌固总长0.5倍之上,否则嵌固作用较弱;基坑地表竖向沉降影响范围约为2倍基坑深度的范围内;滑动面绕过支护桩桩底形成贯通的连通区,通过增加嵌固段的桩长可以提高基坑的稳定性。The excavation and support of deep foundation pits has always been a research hotspot issue.This is mainly because the deep foundation pit projects gradually expand to intensive,and the complexity and regionality of the surrounding environment of the foundation pit also increase.Taking a deep foundation pit project in Lanzhou as the research background,the numerical analysis of the foundation pit project was carried out using PLAXIS 2D.The conclusion shows that the overall displacement development rate of the upper soil nailing wall and the lower pile-anchor support structure system decreases during the excavation and transition process of the two different support systems;the depth of the embedded section decreases.It has a great influence on the horizontal displacement of the supporting pile.It is recommended that the depth of the embedded section entering the pebble stratum is at least 0.5 times the total embedded length,otherwise the embedded effect will be weak;within the range of the depth of the foundation pit;the sliding surface bypasses the bottom of the supporting pile to form a through connection area,and the stability of the foundation pit can be improved by increasing the pile length of the embedded section.

关 键 词：深基坑 桩锚支护 位移 地表沉降 数值分析 

分 类 号：TU753[建筑科学—建筑技术科学]