隧道下穿诱发既有管道-土体非协调变形解析研究  

Analytical Study for Uncoordinated Deformation of Existing Pipeline and Soil Induced by Tunnel Undercrossing

作　　者：潘钦锋 张丙强 黄志斌 PAN Qinfeng;ZHANG Bingqiang;HUANG Zhibin(College of Civil Engineering,Fujian University of Technology,Fuzhou 350118,China;Fujian Railway Construction Co.,Ltd.,China Railway 24th Bureau Group Corporation Limited,Fuzhou 350013,China)

机构地区：[1]福建理工大学土木工程学院,福建福州350118 [2]中铁二十四局集团有限公司福建铁路建设有限公司,福建福州350013

出　　处：《西南交通大学学报》2024年第3期637-645,共9页Journal of Southwest Jiaotong University

基　　金：福建省自然科学基金(2021J011058)。

摘　　要：为分析隧道下穿既有管道施工时既有管道底部脱空对其挠曲响应的影响,提出隧道下穿施工诱发既有管道-土体非协调变形理论模型及其解析解.首先,将既有管道视为无拉力Pasternak地基上的Euler梁,根据管道与底部土体的接触状态,建立下穿施工引起既有管道-土体非协调变形控制方程,并推导出既有管道挠曲计算式;然后,采用提出的理论方法,探讨了既有管道脱空区上部竖向土压力、抗弯刚度及其所处位置地层沉降槽宽度和最大值等参数对其底部脱空区长度的影响;最后,提出下穿施工引起既有管道底部脱空区长度的参数归一化经验计算式,进一步简化新建隧道下穿施工引起既有管道挠曲的计算方法.研究结果表明:既有管道底部脱空区长度与2个归一化参数(既有管道抗弯刚度与地基刚度比、既有管道脱空区上部竖向土压力与地层自由沉降槽最大值比)呈较好的相关性,其拟合公式计算值与理论数据的相关系数接近于1.To analyze the effect of a void under the existing pipeline on its deflection response during tunnel undercrossing construction,a theoretical model and an analytical solution of the uncoordinated deformation of the existing pipeline and soil induced by tunnel undercrossing construction were presented.Firstly,the existing pipeline was regarded as an Euler beam on a tensionless Pasternak foundation.According to the contacting condition of the pipeline and soil,the equations for the uncoordinated deformation control of the pipeline and soil caused by the tunnel undercrossing construction were established,and the corresponding formulas for the pipeline deflection were derived.Secondly,the influence of the parameters on the length of the void under the existing pipeline was discussed by using the proposed theoretical method,including the vertical soil pressure acting above the void,the flexural stiffness,and the width and maximum value of the formation settlement trough at the position where the existing pipeline located.Finally,a normalized empirical formula was proposed for calculating the length of the void under the existing pipeline induced by tunnel undercrossing construction,further simplifying the calculation method of existing pipeline deflection induced by the undercrossing construction of new tunnels.The research results show that the length of the void under the existing pipeline has a good correlation with the two normalized parameters(the ratio of the stiffness of the existing pipeline to the foundation,as well as the ratio of the vertical soil pressure acting above the void of the existing pipeline to the maximum value of the formation settlement trough),and the correlation coefficient between the calculated value of the fitting formula and the theoretical data is close to 1.

关 键 词：管道-土体非协调变形 脱空区长度 PASTERNAK地基 隧道下穿 隧道挠曲轨面变形 

分 类 号：U211.1[交通运输工程—道路与铁道工程]