摘要
顶管开挖通过改变土体中的应力重分布,对既有隧道的变形影响显著,通过FLAC 3D有限差分软件对顶管开挖进行了数值模拟,分析了注浆压力、土仓压力、水平净距对既有隧道变形的影响,得出以下结论:土仓压力和注浆压力对顶管法施工引起的既有隧道变形影响显著。在注浆压力比从0.8增加至1.2的过程中,既有隧道变形增加了约85.1%,且当土仓压力大于0.3 MPa时,既有隧道位移增幅明显。随着水平间距的增加,既有隧道变形逐渐增加,且在距离始发井越近处,既有隧道变形越明显。控制出土量、调整开挖速度可有效控制既有隧道的变形。
Pipe jacking has a significant impact on the deformation of the existing tunnel by changing the stress redistribution in the soil.FLAC 3D finite difference software is used to conduct numerical simulation of pipe jacking,and the influence of grouting pressure,soil chamber pressure and horizontal net distance on the deformation of the existing tunnel is analyzed,and the following conclusions are drawn:Soil silo pressure and grouting pressure have significant influence on the existing tunnel deformation caused by pipe-jacking construction.When the grouting pressure ratio increases from 0.8 to 1.2,the deformation of the existing tunnel increases by about 85.1%,and the displacement of the existing tunnel increases obviously when the soil chamber pressure is greater than 0.3 MPa.With the increase of horizontal spacing,the existing tunnel deformation gradually increases,and the closer to the initial well,the more obvious the existing tunnel deformation.Controlling excavation amount and adjusting excavation speed can effectively control the deformation of existing tunnels.
作者
李栋
平扬
Li Dong;Ping Yang(Shenzhen Longgang Water Engineering Construction Management Center,Shenzhen 518000,China;China Power Construction Eco-Environment Group,Shenzhen 518000,China)
出处
《山西建筑》
2022年第18期4-8,16,共6页
Shanxi Architecture
基金
国家自然科学基金面上基金项目(51878249)。
关键词
顶管开挖
隧道变形
数值模拟
pipe jacki ng excavation
tunnel deformation
the numerical simulation