考虑自重应力的隧道周围土体非线性固结特性分析  

Analysis of Nonlinear Consolidation Characteristics of Soil Around Tunnels Considering Self-Gravity Stress

作　　者：胡安峰[1,2] 陈俞超 肖志荣 谢森林 龚昭祺 HU Anfeng;CHEN Yuchao;XIAO Zhirong;XIE Senlin;GONG Zhaoqi(Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou 310058,China;Center for Balance Architecture,Zhejiang University,Hangzhou 310058,China;School of Civil Engineering and Architecture,Zhejiang University of Science and Technology,Hangzhou 310023,China;Zhejiang Province Architectural Design and Research Institute,Hangzhou 310006,China)

机构地区：[1]浙江大学滨海和城市岩土工程研究中心,杭州310058 [2]浙江大学平衡建筑研究中心,杭州310058 [3]浙江科技学院土木与建筑工程学院,杭州310023 [4]浙江省建筑设计研究院,杭州310006

出　　处：《上海交通大学学报》2025年第4期503-512,共10页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金(51978612)资助项目。

摘　　要：考虑隧道周围土体自重应力,建立饱和土体二维非线性固结控制方程,使用交替隐式差分法对方程进行求解.通过将退化解与已有解析解比较,以及将计算结果与工程实测数据对比,验证了解答的正确性.在此基础上,进一步探究了土体自重应力及固结系数变化对隧道周围土体非线性固结特性的影响规律.结果表明:忽略土体自重应力不仅会导致土层的超静孔压偏大,固结沉降速率偏小,还会使地表沉降终值偏小;在自重应力影响下,压缩指数与渗透指数之比C_(c)/C_(k)越小,土体固结沉降速率越慢,但地表沉降终值不会改变;当C_(c)/C_(k)=1.0时,土体重度越小,其固结速率受初始有效应力分布形式的影响越大,同时地表沉降终值也越大;C_(c)/C_(k)>1.0时渗透系数在固结过程中起主导作用,固结速率随重度增大而减小,而C_(c)/C_(k)<1.0时体积压缩系数的影响效果增强,固结速率变为随重度增大而增大,但两种情形下的地表沉降终值均随土体重度增大而减小.Considering the self-gravity stress of the soil around the tunnel,a two-dimensional nonlinear consolidation control equation for saturated soil was established,and solved using the alternating implicit difference method.The correctness of the solution was verified by comparing the degenerate solution with an existing analytical solution,and by comparing the calculated results with measured data.On this basis,the influence of changes in soil self-gravity stress and consolidation coefficient on the nonlinear consolidation characteristics of the soil around the tunnel was further explored.The results indicate that neglecting the self-gravity stress of the soil leads to a higher excess pore pressure and a lower rate of consolidation settlement,and leads to a lower final surface settlement.Under the influence of self-gravity stress,a smaller ratio of compression index to permeability index C_(c)/C_(k)results in a slower consolidation settlement rate of the soil,but does not affect the final surface settlement.When C_(c)/C_(k)=1.0,a smaller soil self-gravity results in a greater influence of the initial effective stress distribution on the consolidation rate and a higher final surface settlement.When C_(c)/C_(k)>1.0,the permeability coefficient plays a dominant role in the consolidation process,and the consolidation rate decreases as the gravity increases.In contrast,when C_(c)/C_(k)<1.0,the volume compression coefficient becomes more influential,and the consolidation rate increases with the increase of gravity,though the final surface settlement in both cases decreases with increasing gravity.

关 键 词：隧道 非线性固结 有限差分法 自重应力 固结系数 

分 类 号：TU433[建筑科学—岩土工程]