浅埋黄土地层隧道在不同交角下穿既有地下管线的模型试验  

Model test of tunnel passing through existing underground pipelines at different intersection angles in shallow loess ground

作　　者：苏永华[1] 李明[1] SU Yonghua;LI Ming(College of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学土木工程学院,长沙410082

出　　处：《安全与环境学报》2024年第5期1786-1794,共9页Journal of Safety and Environment

基　　金：国家自然科学基金项目(52178330);河南省交通科技项目(2021J7)。

摘　　要：为探究浅埋黄土地层盾构隧道施工下穿对不同特性地下管线的变形受力影响机制,依托河南省某公路隧道工程,以工程黄土为试验材料进行室内模型试验。通过设置3种管隧交角,研究两种接头刚度的非连续管线和连续管线的沉降、弯矩和管土接触压力变化规律,并在管隧正交工况下,研究不同地下管线的遮拦效应及地表沉降变形规律,得出预测管线沉降的拟合公式。结果表明:在3种管隧交角下,地下管线沉降存在3个阶段,在管线沉降集中区阶段低密度聚乙烯(Low Density Polyethylene,LDPE)接头非连续管线的平均沉降增长速率是聚氯乙烯(Polyvinyl Chloride,PVC)接头非连续管线的2倍;管隧交角的减小,使得非连续管线的最大正负弯矩均减小,PVC接头非连续管线弯矩曲线由“W”形转变为“V”形;管隧交角和接头刚度对土压力变化曲线和峰值位置几乎无影响,土压力变化均呈“M”形;在管隧正交下,管线整体刚度越大对地表沉降抑制作用越显著,管线沉降与地表沉降呈指数关系。To investigate the mechanism of deformation force on underground pipelines with different characteristics under the tunnel construction of shield tunneling in shallowly buried loess layer,in this paper,based on a highway tunnel project in Henan Province,an indoor modeling test is carried out with engineering loess as the experimental material.The settlement,bending moment,and pipe-soil contact pressure change rules of discontinuous and continuous pipelines with two joint stiffnesses are investigated by setting up three kinds of pipelines and tunnel intersection angles.In the context of the vertical intersection of pipelines and tunnels,we investigate the impact of different types of underground pipelines on surface settlement deformation,from which we derive a formula to precisely predict the amount of pipeline settlement.The test results indicate that underground pipelines undergo three stages of settlement under three different types of pipe-tunnel intersection angles.In the stage of the pipeline settlement concentration zone,the average settlement growth rate of Low Density Polyethylene(LDPE)joints in the discontinuous pipeline is twice that of PVC joints in the discontinuous pipeline.The stiffness of the discontinuous pipe joints and the angle of intersection between the pipe and the tunnel affect both the value and the distribution of the bending moments in the pipeline.As the angle of intersection between the pipe and the tunnel decreases,the maximum positive and negative bending moment values of discontinuous pipelines decrease,and the bending moment distribution pattern of non-continuous pipelines with Polyvinyl Chloride(PVC)joints changes from"W"type to"V"type.The angle of intersection between the tunnel and the pipeline and the stiffness of the pipeline joints hardly influence the curve of soil pressure change and the location of the maximum soil pressure,and the shape of the pattern of soil pressure change resembles the letter"M".In the case of orthogonal engineering conditions for pipelines and tunnel

关 键 词：安全工程 接头刚度 非连续管线 地表沉降 遮拦效应 

分 类 号：X951[环境科学与工程—安全科学]