摘要
文章以某城市地铁车站深基坑为依托,基于有限差分方法和流固耦合原理,利用FLAC3D对基坑进行三维流固耦合降水开挖数值模拟,分析了降水开挖和未降水开挖情况下引起的坑底隆起变形规律、围护结构侧向变形规律以及下卧隧道变形机理。研究表明:坑底隆起变形在短边和长边方向上,分别呈现出开口向下的抛物线形和驼峰状,降水开挖比未降水开挖情况引起的坑底隆起变形减小约50%;围护结构变形呈现内凸形,中部凸起最大值约为35 mm,降水开挖引起的围护结构变形比未降水开挖增大约5 mm;降水开挖比未降水开挖引起的隧道隆起变形要小约50%,但造成的地表沉降值要大约10倍。模拟值与实测值规律基本一致,模拟效果较好。
In view of the deep foundation pit of a metro station in a city,and based on the finite difference method and the fluid-mechanics interaction principle,the numerical simulation of three-dimensional fluid-mechanics interactive dewatering excavation of foundation pit using FLAC3D is carried out,and the deformation law of the bottom of pit and lateral deformation of the enclosure and deformation mechanism of underlying tunnel by dewatering excavation and non-dewatering excavation are analyzed.The research shows that the deformation of the bottom of the pit is in the direction of the short side and the long side,revealing the downward parabolic shape and the hump shape,respectively.The deformation of the bottom of the pit caused by dewatering excavation is reduced by about 50%compared with non-dewatering excavation.The deformation of the envelope structure is convex,and the maximum value of the middle projection is about 35 mm.The deformation of the envelope structure caused by dewatering excavation is about 5 mm larger than that caused by non-dewatering excavation.The deformation of tunnel uplift caused by dewatering excavation is about 50%smaller than that caused by non-dewatering excavation,but the ground settlement value caused by dewatering excavation is about ten times larger than that caused by non-dewatering excavation.The simulation results are consistent with the measured results.
作者
汪鹏程
王景
周守强
WANG Pengcheng;WANG Jing;ZHOU Shouqiang(School of Civil and Hydraulic Engineering, Hefei University of Technology, Hefei 230009, China)
出处
《合肥工业大学学报（自然科学版）》
CAS
北大核心
2020年第4期499-506,共8页
Journal of Hefei University of Technology：Natural Science
关键词
深基坑
降水开挖
流固耦合
数值模拟
变形
deep foundation pit
dewatering excavation
fluid-mechanics interaction
numerical simulation
deformation
作者简介
汪鹏程(1968-),男,安徽桐城人,博士,合肥工业大学副教授,硕士生导师。
