拉林铁路板块缝合带隧道地应力分析  

In-Situ Stress Analysis of Tunnel in Plate Suture Zone of Lhasa-Nyingchi Railway

作　　者：欧小强 王奭 李永亮 刘志强[1] 郑宗溪[4] 吴剑[1] Ou Xiaoqiang;Wang Shi;Li Yongliang;Liu Zhiqiang;Zheng Zongxi;Wu Jian(China Railway South-west Research Institute Co.,Ltd.,Chengdu 611731,China;China Railway Qinghai-Tibet Group Co.,Ltd.,Xining 810007,China;Lhasa-Nyingchi Railxvay Headquarter,China Railway Corporation,Lhasa 850000,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]中铁西南科学研究院有限公司,成都611731 [2]中国铁路青藏集团有限公司,西宁810007 [3]中国铁路总公司拉林铁路建设总指挥部,拉萨850000 [4]中国中铁二院工程集团有限责任公司,成都610031

出　　处：《吉林大学学报（地球科学版）》2019年第6期1689-1697,共9页Journal of Jilin University：Earth Science Edition

基　　金：中国铁路总公司科技研究开发计划项目(2017G006-B)~~

摘　　要：青藏高原板块缝合带为印度板块和欧亚板块两大陆块的缝合区域,带区地质条件复杂,构造运动强烈。川藏线拉林铁路几乎沿雅鲁藏布江缝合带展布,高地应力问题十分突出,但目前针对板块缝合带隧道的地应力研究相对较少。本文采用空心包体法对拉林铁路沿线隧道进行了原位地应力测量,并与成兰、兰渝和锦屏等几个典型工程的地应力进行对比分析。研究表明:拉林铁路沿线隧道埋深大,构造应力突出,总体表现为最大水平主应力>垂直主应力>最小水平主应力;平均侧压系数(1.0~1.5)分布较为集中且处于较高水平;最大主应力量值大多在20~50MPa之间,最大主应力与埋深的梯度为0.0337MPa/m,方向以北北西-北北东向为主。建议采用仰拱结构减小隧道墙脚处的应力集中现象。The Qinghai-Tibetan Plateau suture zone lies between the continental blocks of the India plate and the Eurasian plate,where the geological conditions are complex,and the tectonic movement is strong.The Lhasa-Nyingchi Line of Sichuan-Tibet Railway is almost along the Yarlung Zangbo suture,and its high ground stress causes problems frequently.At present,the study on in-situ stress of the tunnel in plate suture zone is relatively rare.The in-situ stress measurement of the tunnels along the railway was carried out by hollow inclusion stress-relief m ethod,and the in-situ stresses with several typical projects such as Chengdu-Lanzhou Railway,Lanzhou-Chongqing Railway,and Jinping Hydropower Station were analyzed and compared with each other.The results show that the tunnels along the Lhasa-Nyingchi Railway have large buried depth,and the prominent tectonic stress shows as maximum horizontal principal stress>vertical principal stress>minimum horizontal principal stress.The average lateral pressure coefficient distribution is relatively concentrated(1.0-1.5),and at a high level.Most of the maximum principal stresses are between 20-50 MPa,the gradient between maximum principal stress and burial depth is 0.0337 MPa/m,and the direction of maximum principal stress is NNW-NNE.It is suggested that the invert structure should be used to reduce the stress concentration at the foot of tunnel wall.

关 键 词：板块缝合带 地应力 铁路隧道 最大主应力 空心包体法 

分 类 号：U452.1[建筑科学—桥梁与隧道工程]