砂质泥岩深基坑桩锚支护结构施工力学行为研究  

Study on Construction Mechanical Behavior of Pile Anchor Supporting Structure in Sandy Mudstone Deep Foundation Pit

作　　者：屈家奎 QU Jiakui(The Third Engineering Co.,Ltd.of China Railway 20th Bureau Group,Chongqing 400065,China)

机构地区：[1]中铁二十局集团第三工程有限公司,重庆400065

出　　处：《科技和产业》2022年第9期301-307,共7页Science Technology and Industry

基　　金：重庆市科技型企业技术创新与应用发展专项(cstc2020kqjscx-phxm0183)。

摘　　要：砂质泥岩由于强度低、易扰动等特点,导致其深基坑支护难度大、施工风险高,开展相关施工力学行为研究具有重要意义。以重庆轨道10号线兰花湖明挖地下停车场深基坑工程为对象,采用数值模拟、现场实测和理论计算相结合的方法,探究深厚砂质泥岩基坑桩锚支护结构的受力特征及变形规律。结果表明:围护桩的水平位移变形曲线在开挖初期呈现出三角形分布,开挖至中后期表现为抛物线的特征;随着基坑开挖,周边地表沉降逐渐增加,沉降曲线大致满足正态分布曲线,沉降影响范围距基坑边缘约50 m;锚索轴力在砂质泥岩深基坑施工前期变化较为明显,距离锚索位置15 m后的开挖对锚索轴力影响较小。Due to the characteristics of low strength and easy disturbance,sandy mudstone has great difficulty in supporting deep foundation pit and high construction risk.It is of great significance to carry out the research on relevant construction mechanical behavior.Taking the deep foundation pit project of lanhuahu open cut underground parking lot of Chongqing Rail Transit Line 10 as the object,the stress characteristics and deformation law of pile anchor support structure of deep sandy mudstone foundation pit are explored by using the combination of numerical simulation,field measurement and theoretical calculation.The results show that the horizontal displacement deformation curve of retaining pile presents a triangular distribution in the early stage of excavation and a parabola in the middle and late stage of excavation.With the excavation of foundation pit,the surrounding surface settlement increases gradually,the settlement curve roughly meets the normal distribution curve,and the influence range of settlement is about 50 m away from the edge of foundation pit.The axial force of anchor cable changes obviously in the early stage of sandy mudstone deep foundation pit construction.And the excavation about 15 m away from the anchor cable position has little impact on the axial force of anchor cable.

关 键 词：砂质泥岩深基坑 数值模拟 开挖监测 桩锚支护 基坑变形 

分 类 号：TU473.2[建筑科学—结构工程]