考虑脱空效应的隧道开挖诱发上覆管道变形分析  

Analysis on Overlying Pipe Deformation Induced by Tunnel Excavation Considering Detachment Effect

作　　者：杨明辉[1,2] 郑彬彬 靳正付 付大喜 Yang Minghui;Zheng Binbin;Jin Zhengfu;Fu Daxi(School of Civil Engineering,Hunan University,Changsha 410082,P.R.China;School of Architecture and Civil Engineering,Xiamen University,Xiamen,Fujian 361005,P.R.China;Henan Xinrong Expressway Construction Co.,Ltd.,Luoyang,Henan 4710271,P.R.China)

机构地区：[1]湖南大学土木工程学院,长沙410082 [2]厦门大学建筑与土木工程学院,福建厦门361005 [3]河南省新融高速公路建设有限公司,河南洛阳471027

出　　处：《地下空间与工程学报》2023年第5期1433-1443,共11页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金(51278184,50708030);河南省交通科技计划项目(2019J-2-12)。

摘　　要：考虑黄土区浅埋隧道的工程特点以及土体大变形特性,将浅埋隧道下穿开挖过程上覆管道分为管土脱空区与管土变形协调区,提出考虑管土脱空的相互作用计算模型。在考虑管道埋深对地基基床反力模量影响的基础上,采用Pasternak半无限弹性地基梁模型考虑土体连续性,采用二阶段分析方法将土体自由位移荷载施加于管道,分别建立脱空区、协调区的管道力学模型与微分控制方程,并给出理论解答与管-土脱空区范围的试算步骤。与已有模型试验监测数据的对比验证了计算方法的精确度,发现不考虑管土脱空现象时的管道变形计算方法偏于保守。最后,对管道变形的各主要影响因素进行了对比分析,结果表明:管道最大变形量随地层损失增大而增大,随管隧间距、管道刚度、土体强度增大而减小,但减小的幅度均随各参数的增加而减缓;脱空区范围随管道刚度、土体弹性模量及管隧间距增大而增大,而表征管土脱空程度指标即最大变形差随管道刚度增大而增大,但随着土体弹性模量以及管隧间距的增大却呈减小趋势。Considering the engineering characteristics of shallow buried tunnels in loess area and probable large deformation of soil,the overlying pipe was divided into pipe-soil detached area and pipe-soil deformation coordination area during excavation process,and a calculation model considering pipe-soil detachment interaction was proposed.On the basis of considering the influence of pipe buried depth on subgrade reaction modulus,the modified semi-infinite Pasternak elastic foundation beam model was used to consider soil continuity.After applying freesoil displacement load to pipe by two-stage method,the mechanical models and governing differential equations of both the detached area and coordination area were established,and the theoretical solution was given.Then,through comparison with the existing model test data,the proposed method in this paper was verified to be accurate,and the solution of pipe deformation without considering detachment was conservative.Finally,the main influencing factors of pipe deformation were compared and analyzed.Results show that,the maximum deformation of pipe increases with the increase of soil loss,and decreases with the increase of pipe-tunnel spacing,pipe stiffness and soil strength,but the magnitude of decreases are slowed down with the increase of each parameter.The range of detached area increases with increase of pipe stiffness,soil elastic modulus and pipe-tunnel spacing,while the maximum deformation difference which represents the degree of pipe-soil detachment increases with the increase of pipe stiffness,but contradicts with soil elastic modulus and pipe-tunnel spacing.

关 键 词：黄土区 浅埋隧道 下穿管道 管土脱空 半无限长梁 

分 类 号：TU470[建筑科学—结构工程]