富水岩溶地区新建隧道对上跨既有隧道渗流场及应力场的影响机制  

Influence mechanism of new tunnel on seepage field and stress field of overpass existing tunnel in water-rich karst area

作　　者：莫小兵 郝世全 李伟 郭辉 邹俊鹏 马彩霞[5] MO Xiaobing;HAO Shiquan;LI Wei;GUO Hui;ZOU Junpeng;MA Caixia(China Railway Development Investment Group Co.,Ltd.,Kunming 650504,China;China Railway Third Bureau Group Fifth Engineering Co.,Ltd.,Huaihua 418099,China;Key Laboratory of Geological Survey and Evaluation of Ministry of Education,China University of Geosciences(Wuhan),Wuhan 430074,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;Art Academy,Hubei University of Education,Wuhan 430205,China)

机构地区：[1]中铁开发投资集团有限公司,云南昆明650504 [2]中铁三局集团第五工程有限公司,湖南怀化418099 [3]中国地质大学(武汉)地质探测与评估教育部重点实验室,湖北武汉430074 [4]中国地质大学(武汉)工程学院,湖北武汉430074 [5]湖北第二师范学院艺术学院,湖北武汉430205

出　　处：《安全与环境工程》2025年第2期151-159,共9页Safety and Environmental Engineering

基　　金：国家自然科学基金项目(42277173)。

摘　　要：富水岩溶地层中新建隧道跨越既有隧道施工时,区域渗流场及应力场发生变化,导致新建隧道以及既有隧道的安全性受到威胁,存在隧道渗涌水及结构失稳的风险。通过有限元-离散元耦合方法(FDEM)孔隙-应力渗流模型研究了地下水水位变化对杨木岭隧道开挖后隧道模型渗流场、应力场和位移场的影响,以及隧道模型中天然裂缝密度变化对渗流场和位移场的影响。结果表明:杨木岭隧道开挖后周围孔隙水压力形成降落漏斗,随着地下水水位的升高,降落漏斗范围增大;隧道模型的最大水平位移和最大压应力随着地下水水位的升高而增大,最大竖直位移和最大拉应力则减小;考虑天然裂隙分布时,孔隙水压力的分布受裂缝密度和位置的影响显著,且孔隙水压力越小的区域,裂缝的阻碍效果愈加明显,同时天然裂缝对隧道模型中水平位移的分布有较大影响,且裂缝越靠近隧道影响越明显。When a new tunnel overpassing an existing tunnel in water-rich karst stratum is constructed,the regional seepage field and stress field will change,which will threaten the safety of the new tunnel and the existing tunnel,and lead to the risk of tunnel seepage and structural instability.In this paper,the influence of groundwater level change on the seepage field,stress field and displacement field of the Yangmuling Tunnel model after excavation is studied by finite-discrete element method(FDEM)pore-stress seepage model,as well as the influence of natural crack density change on seepage field and displacement field in the tunnel model.The results show that the surrounding pore water pressure forms a depression cone after the excavation of the Yangmuling Tunnel.With the increase of groundwater level,the range of depression cone is larger.Moreover,the maximum horizontal displacement and maximum compressive stress of the tunnel model increase with the increase of the groundwater level,and the change of the maximum vertical displacement and maximum tensile stress are the opposite.In the tunnel model with natural cracks,the distribution of pore water pressure is significantly affected by the crack density and location.In the zones with the smaller pore water pressure,the hindering effect of cracks is more obvious.Natural cracks have a great influence on the distribution of horizontal displacement in the tunnel model,and as the crack is closer to the tunnel,this phenomenon is more significant.

关 键 词：富水岩溶区 隧道 流固耦合 渗流场 应力场 天然裂缝 有限元-离散元耦合方法(FDEM) 

分 类 号：X93[环境科学与工程—安全科学] U452.11[建筑科学—桥梁与隧道工程]