基于广义Voigt模型的半渗透边界隧道周围饱和软土固结分析  

Consolidation analysis of saturated soft soils surrounding tunnels with semi-permeable boundary based on the generalized Voigt model

作　　者：谢森林 胡安峰[1,3] 肖志荣 汪美慧 胡训健 陈俞超 XIE Sen-lin;HU An-feng;XIAO Zhi-rong;WANG Mei-hui;HU Xun-jian;CHEN Yu-chao(Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou,Zhejiang 310058,China;The Architectural Design&Research Institute of Zhejiang University Co.,Ltd.,Hangzhou,Zhejiang 310058,China;Center for Balance Architecture,Zhejiang University,Hangzhou,Zhejiang 310058,China;School of Civil Engineering and Architecture,Zhejiang University of Science and Technology,Hangzhou,Zhejiang 310023,China;School of Civil Engineering,Wuhan University,Wuhan,Hubei 430072,China)

机构地区：[1]浙江大学滨海和城市岩土工程研究中心,浙江杭州310058 [2]浙江大学建筑设计研究院有限公司,浙江杭州310058 [3]浙江大学平衡建筑研究中心,浙江杭州310058 [4]浙江科技学院土木与建筑工程学院,浙江杭州310023 [5]武汉大学土木建筑工程学院,湖北武汉430072

出　　处：《岩土力学》2024年第7期2024-2036,共13页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52378419,No.51978612);国家留学基金(No.202306320346);浙江省新苗人才计划项目(No.2023R401189)。

摘　　要：引入衬砌半渗透边界条件,使用广义Voigt黏弹性模型描述隧道周围饱和软黏土的流变特性,基于Terzaghi-Rendulic理论建立以超孔隙水压力为变量的软土二维流变固结控制方程。采用保角变换和分离变量方法,得到超孔隙水压力关于时间和空间变量的两个独立方程,依次使用Laplace变换法与部分分式展开法得到时域内超孔隙水压力消散解。将广义Voigt模型退化为已有四元件Burgers模型和五元件模型并与其对比,验证解答的可靠性。基于建立的解答,分析衬砌透水程度、Kelvin体数量、独立Newton黏壶黏滞系数、隧道埋深等因素对超孔隙水压力消散与分布的影响规律。结果表明:衬砌与土体的相对渗透系数比越大,超孔隙水压力的消散起始时间越早,消散速度越快。Kelvin体数量越多,超孔隙水压力消散越慢;独立黏壶黏滞系数越大,其产生的黏滞变形越小,超孔隙水压力消散速率越快;隧道埋深越大,土体渗流路径越长,超孔隙水压力消散越慢;当相对渗透系数比为0.01时,超孔隙水压力随着到隧道外壁距离的增大而逐渐减小,当相对渗透系数比为1.00时,超孔隙水压力随着距离的增大而出现先增大后减小的现象;随着相对渗透系数比的增加,Kelvin体数量对超孔压消散的影响越小,不同独立黏滞系数带来的超孔压消散差异逐渐减小,隧道衬砌作为土层内部新透水边界的作用越突出。This study investigates the rheological properties of saturated soft clay surrounding a tunnel using the generalized Voigt viscoelastic model.The model incorporates linear semi-permeability boundary conditions to describe the behavior of the clay.Furthermore,two-dimensional rheological consolidation control equations are derived based on the Terzaghi-Rendulic theory,considering the excess pore water pressure as a variable.To solve the equations,conformal transformation and separation of variables methods are employed,resulting in two independent equations representing the excess pore pressure in terms of time and space variables.The Laplace transformation and partial fractional summation method are then utilized to obtain the solution for excess pore pressure dissipation in the time domain.The reliability of the solution is verified by comparing it with the existing four-element Burgers and five-element model,both of which are derived from the generalized Voigt model.Furthermore,the influence of liner permeability,Kelvin body number,independent Newtonian dashpot viscosity coefficient,and tunnel depth on the dissipation and distribution of excess pore pressure is analyzed based on the established solutions.The findings indicate that a higher relative permeability of the liner and soil leads to an earlier onset of excess pore pressure dissipation and a faster dissipation rate.Increasing the number of Kelvin bodies results in slower dissipation rate.Moreover,larger independent viscous coefficients lead to smaller viscous deformation and faster dissipation rates.Additionally,greater tunnel depth prolongs soil percolation path,slowing down the dissipation of excess pore pressure.When the relative permeability coefficient is 0.01,the excess pore pressure gradually decreases with distance from the outer wall of the tunnel.However,when the relative permeability coefficient is 1,the excess pore pressure initially increases and then decreases with distance.As the relative permeability coefficient increases,the influence of

关 键 词：黏弹性地基 半渗透边界 广义Voigt模型 超孔隙水压力 流变固结 

分 类 号：TU441[建筑科学—岩土工程]