逆断层黏滑作用下隧道力学行为研究  

Mechanical behavior of tunnel under stick-slip action of reverse fault

作　　者：郭翔宇 耿萍[1,2] 丁梯 王琦 杨琪[1,2] 何悦[1,2] GUO Xiangyu;GENG Ping;DING Ti;WANG Qi;YANG Qi;HE Yue(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;MOE Key Lab of Transportation Tunnel Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]交通隧道工程教育部重点实验室,成都610031 [3]中铁二院工程集团有限责任公司,成都610031

出　　处：《振动与冲击》2021年第17期249-258,共10页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(51878566);四川省重点研发项目(2020YFS0294)。

摘　　要：西南地区板块运动活跃,隧道不可避免的会穿越活动断裂带,活动断裂带的黏滑作用将对隧道结构的安全和稳定性构成巨大威胁。首先建立300 km×100 km的空间大尺度板块挤压模型,通过对板块施加挤压速率,计算板块运动20万年期间逆断层黏滑作用的产生及变形特点,然后将断层黏滑时刻位移施加到精细有限元模型上,分析隧道结构在逆断层黏滑作用下的力学与损伤行为。结果显示黏滑时刻断层面处剪切应力呈现“骤降-再回升”状态,同时断层上盘产生脉冲型速度时程;断层顶面位移特征曲线可分为单峰值曲线和双峰值曲线,最终均保持永久位移;地层刚度越大,隧道衬砌在黏滑作用下产生的裂缝宽度越大,裂缝拓展范围则越小。所研究工况下,不同地质条件时,衬砌最大裂缝宽度为19.8 cm,最大扩展长度为55.4 m。该研究成果可为隧道在逆断层黏滑作用下的结构破坏特点提供参考。Plate movement is active in southwest China.Tunnels will inevitably cross active fault zones.The stick-slip effect of active fault zones will pose a great threat to safety and stability of tunnel structures.Here,firstly,a spatial large-scale plate extrusion model of 300 km×100 km was established.Through applying the extrusion rate to the plate,generation and deformation characteristics of reverse fault stick-slip action during 200000 years of plate movement were calculated,and then displacement at time of fault stick-slip was applied to the fine finite element model to analyze mechanical and damage behavior of tunnel structure under the action of reverse fault stick-slip.The results showed that shear stress at fault presents a state of“sudden drop and then rise”at time of stick-slip,and a pulse velocity time history is generated on hanging wall of fault;displacement characteristic curve on fault top surface can be divided into single-peak curve and double-peak curve,finally both of them maintain permanent displacement;the larger the stratum stiffness,the wider the crack width generated by tunnel lining under stick-slip and the smaller the crack expansion range;under working conditions studied and different geological conditions,the maximum crack width of tunnel lining is 19.8 cm,and the maximum crack expansion length is 55.4 m;the study results can provide a reference for studying structural failure characteristics of tunnel under action of reverse fault stick-slip.

关 键 词：逆断层 黏滑 隧道 裂缝 

分 类 号：U451[建筑科学—桥梁与隧道工程]