岩土力学2025，Vol.46Issue(6)：1811-1824,14.DOI:10.16285/j.rsm.2024.0525
基底均匀膨胀作用下黄土-泥岩复合地层隧道衬砌力学响应研究
Mechanical response of tunnel lining in loess-mudstone composite strata under uniform expansion of foundation
摘要
Abstract
Strata structure of loess area mostly features a dualistic structure of loess and mudstone.When tunnels traverse mudstone and loess-mudstone composite strata,groundwater tends to redistribute and accumulate at the base of the inverted arch.The interaction between mudstone and water causes tunnel heave,and the lithological differences between the strata significantly affect the deformation and stress characteristics of the tunnel lining.Based on a tunnel project in Tianshui City,Gansu Province,model tests were conducted on tunnel in pure mudstone and loess-mudstone composite strata with the interface at the arch waist.Displacement was applied beneath the inverted arch to simulate the swelling effect of mudstone-water interaction.Differences in internal force,deformation,and failure characteristics of the lining under two loading conditions were investigated,and numerical simulations were conducted for comparison and verification.The differences in internal force,the deformation and failure characteristics of lining under two loading conditions were investigated,and the corresponding conditions numerical simulation was conducted for comparison and verification.The results show that:(1)Expansion deformation due to forced displacement at the model's base can be divided into two stages:the base soil compaction stage and the equivalent transfer stage of base displacement.(2)With the elastic modulus ratio of mudstone to loess approximately 2:1,the loess stratum exhibits smaller overall stiffness,resulting in larger lining deformation and even larger heave displacement in inverted arch.The arch waist at the interface is more prone to outward expansion,with an expansion deformation of 9.2 mm,about three times that of the pure mudstone stratum.Stress concentration tends to occur at the lining section near the interface.(3)In both strata,the inverted arch and arch foot positions are prone to cracking and damage.Additionally,in the composite strata,the lining arch shoulder shows a high risk of cracking,with cracks at the arch foot tending to expand towards the arch waist.(4)Compared to pure mudstone stratum,the loess near the interface in loess-mudstone strata exerts a load release effect on the heave of inverted arch.The loess at the interface compresses and absorbs some of the heave force,thereby delaying the critical tensile failure time of the filling layer.The results can provide valuable references for theoretical analysis,design and construction of tunnels in similar composite strata.关键词
仰拱底鼓/交界地层/模型试验/数值模拟Key words
inverted arch floor heave/interface strata/model experiment/numerical simulation分类
交通工程引用本文复制引用
梁庆国,李景,张崇辉,刘彤彤,孙志涛..基底均匀膨胀作用下黄土-泥岩复合地层隧道衬砌力学响应研究[J].岩土力学,2025,46(6):1811-1824,14.基金项目
国家自然科学基金(No.51968041) （No.51968041）
甘肃省重点研发计划项目(No.25YFGA052) （No.25YFGA052）
兰州交通大学青年科学基金(No.2024032) （No.2024032）
甘肃省优秀研究生"创新之星"(No.2025CXZX-658) （No.2025CXZX-658）
中铁一院科技项目(No.2022KY32YB-02).This work was supported by the National Natural Science Foundation of China(51968041),the Gansu Provincial Key Research and Development Program(25YFGA052),the Youth Science Foundation of Lanzhou Jiaotong University(2024032),the Innovation Star for Outstanding Graduate Students of Gansu Province(2025CXZX-658)and the China Railway First Survey and Design Institute Science and Technology Project(2022KY32YB-02). （No.2022KY32YB-02）
