高铁海底隧道矿山-盾构对接段渗流应力耦合特征研究  

Characteristics of seepage-stress coupling in mine-shield docking section of high speed railway subsea tunnel

作　　者：靖一峰 汪波[1] 梅洁 刘金炜 孟庆余 JING Yifeng;WANG Bo;MEI Jie;LIU Jinwei;MENG Qingyu(Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;Institute of Urban Rail Transportation,Southwest Jiaotong University,Chengdu 611756,China;China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]西南交通大学城市轨道交通学院,四川成都611756 [3]中国铁路设计集团有限公司,天津300308

出　　处：《水资源与水工程学报》2024年第5期181-190,共10页Journal of Water Resources and Water Engineering

基　　金：中国博士后科学基金项目(BX20230297);中央高校基本科研业务费专项资金项目(2682022CX073);中国铁路设计集团有限公司科技开发课题(2020YY240610);中国国家铁路集团有限公司科技研究开发计划项目重大课题(K2020G033)。

摘　　要：矿山法与盾构法水下对接施工是海底隧道修建的关键技术难题,明确渗流-应力耦合特征是隧道对接段建设和运营安全的重要保障。采用有限元软件对现场对接施工方案进行三维数值模拟,基于数值模拟结果,分析了隧道不同施工区段的渗流特征、位移变形和应力变化规律,揭示了隧道矿山-盾构对接段施工对围岩扰动的渗流-应力耦合机制。结果表明:隧道开挖后,围岩中的孔隙水向隧道洞周及开挖面汇集并不断补给,导致孔隙水压力减小,并形成降水漏斗,隧道洞周渗流速度增加,在开挖阶段涌水量较大;受水力梯度影响,拱底处孔隙水压力最大,施工可通过设置排水措施,进行引排泄压;隧道断面开挖时,位移变形产生突变,受开挖面排水泄压影响,在隧道断面开挖前,拱底处产生竖向位移沉降;相较于盾构法,矿山法施工的扰动程度更大,在不同施工段落区段,采用矿山法施工的开挖断面主应力分布一致。研究可为海底隧道矿山法与盾构法水下对接工程安全性评价提供参考。Underwater docking construction by mine and shield method is a key technical issue in the construction of subsea tunnels,and understanding the seepage-stress coupling characteristics is the premise of safe construction and operation of the docking section of tunnels.This study employed a finite element software to carry out three-dimensional numerical simulation of on-site docking construction scheme.Based on the simulation results,the seepage characteristics,displacement deformation and stress change rules of different construction sections of the tunnel were analyzed,which revealed the seepage-stress coupling mechanism of the construction of the tunnel mine-shield docking section on the surrounding rock disturbance.The results show that after tunnel excavation,the pore water in the surrounding rock pools and continuously recharges to the tunnel cave perimeter and the excavation surface,resulting in a reduction of pore water pressure,the formation of precipitation funnels,an increase in the seepage rate around the tunnel cave perimeter,and a large amount of water influx during the excavation stage.Affected by the hydraulic gradient,the pore water pressure at the bottom of the arch is the largest,but setting up drainage measures can lead and drain the pressure during construction.During tunnel excavation,displacement deformation increases abruptly,and due to the influence of dewatering and pressure relief at the excavation face,vertical settlement occurs at the crown of the tunnel section before excavation.Compared with the shield method,the disturbance degree of the mine method construction is greater,and the distribution of principal stresses in the excavation sections using the mine method are consistent in different construction sections.The study can provide a reference for the safety evaluation of the underwater docking projects by mine and shield method in subsea tunnels.

关 键 词：海底隧道 矿山法 盾构法 对接段 渗流应力耦合 

分 类 号：TV554[水利工程—水利水电工程] U25[交通运输工程—道路与铁道工程]