摘要
以乌鲁木齐地铁8楼站为工程背景,基于地表沉降的实测数据,运用Midas建立“导洞-扣拱-土体”数值模型,分析洞桩法地铁车站施工对地表沉降的影响.结果表明:导洞开挖和扣拱施工2个关键阶段引起的地表沉降占总沉降的80%;导洞开挖阶段“先上后下”和“先中后边”引起的地表沉降最小,开挖面越小面距越大,地表沉降越不明显;扣拱施工阶段随着中拱施作的完成和边拱施作的开始,拱顶的位移和最大主应力都会出现急剧增大的现象;对实测地表沉降和模拟数据进行对比,发现两者具有相同的变化规律,但由于实际土体存在固结沉降,数值模拟结果往往偏于安全.
Taking Urumqi metro station on the eighth floor as the engineering background and based on the on-site monitoring data of surface settlement,a“guide holes-arch-soil”numerical simulation model was established by Midas to analyze the influence of the Pile-Beam-Arch Method in metro station construction on surface settlement.The results show that the surface settlement caused by the two key stage of guide-holes excavation and the arch construction account for 80%of the total settlement.During the excavation stage of the guide-holes,the surface settlement caused by“first up,then down”and“first middle,then side”is the smallest.The smaller the excavation surface and the larger the surface distance is,the less obvious the surface settlement is.During the arch construction stage,the settlement and the maximum principal stress will increase sharply with the completion of the middle arch and the beginning of the side arch.By comparing the on-site monitoring data of surface settlement with the simulated data,it is found that the two have the same change law.But the simulation results are safer due to the consolidation settlement of the actual soil.
作者
李世久
乔向进
LI Shi-jiu;QIAO Xiang-jin(National Experimental Teaching Demonstration Center of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;College of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《兰州工业学院学报》
2020年第1期38-43,共6页
Journal of Lanzhou Institute of Technology
关键词
洞桩法
数值模拟
现场监测
地表沉降
PBA
numerical simulation
on-site monitoring
surface settlement
作者简介
李世久(1995-),男,河南南阳人,硕士生.
