渗流对粉质黏土地基地下结构浮力影响的数值模拟研究  

Numerical Simulation Study on Influence of Seepage on Buoyancy of Underground Structures with Silty Clay Foundation

作　　者：马宇佳 孙超[1] 汪鹏 曹镇 陈宇轩 MA Yujia;SUN Chao;WANG Peng;CAO Zhen;CHEN Yuxuan(College of Exploration Engineering,Jilin Jianzhu University,Changchun 130118,Jilin,China)

机构地区：[1]吉林建筑大学测绘与勘查工程学院,吉林长春130118

出　　处：《建筑施工》2024年第1期28-32,共5页Building Construction

基　　金：住房和城乡建设部研究开发项目(2012-k3-16);吉林建筑大学国家级创新训练项目(202210191019)。

摘　　要：为研究城市地下空间大量开发所导致的地下结构抗浮问题,以长春地区广泛分布的粉质黏土为研究对象,针对潜水渗流这种较为常见的地下水渗流形式,采取理论分析和FLAC 3D数值模拟相结合的方法,研究了潜水下渗情况下,地下水的渗流特征以及其对建筑物现场孔隙水压力的影响,并进行弱透水粉质黏土的层厚、水力梯度等其他影响因素的分析。结果表明:弱透水粉质黏土基底上孔压的大小和基底处于弱透水层中的位置有关,愈接近弱透水层底部,孔隙水压力愈小,地下结构所受浮力亦愈低。承压水含水层上渗情况,基底处孔压主要由下承压水水头决定,基底上孔压与承压水水头呈线性增长。研究成果可为长春地区粉质黏土地基地下结构的抗浮设计提供一定的借鉴。In order to study the anti-floating problem of underground structures caused by the large-scale development of urban underground space,the silty clay widely distributed in Changchun area is taken as the research object.In view of the subsurface seepage,which is a common form of groundwater seepage,the method of combining theoretical analysis with FLAC 3D numerical simulation is adopted to study the groundwater seepage characteristics and its impact on the pore water pressure of the building site,and the thickness of the weak permeable silty clay layer,hydraulic gradient and other factors are analyzed.The results show that the pore water pressure on the base of weakly permeable silty clay is related to the position of the base in the aquitard.The closer it is to the bottom of the aquitard,the smaller the pore water pressure is and the lower the buoyancy on the underground structure is.In the case of upward seepage of confined water aquifer,the pore pressure at the basement is mainly determined by the lower confined water head,and the pore pressure on the basement increases linearly with the confined water head.The research results can provide a reference for the anti-floating design of the structure under the silty clay foundation in Changchun area.

关 键 词：地下结构抗浮 地下水渗流特征 水力梯度 数值模拟 

分 类 号：TU46[建筑科学—结构工程]