远场地震作用下跨断层深埋隧道结构的动力变形破坏特征  

Dynamic deformation and failure characteristic of deep buried tunnel crossing fault under far-field earthquake loading

作　　者：蒋宇静[1] 王兴达 张学朋[1] JIANG Yujing;WANG Xingda;ZHANG Xuepeng(State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao 266590,Shandong,China;College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,Shandong,China)

机构地区：[1]山东科技大学矿山灾害预防控制省部共建国家重点实验室(培育),山东青岛266590 [2]山东科技大学能源与矿业工程学院,山东青岛266590

出　　处：《隧道与地下工程灾害防治》2023年第3期1-11,共11页Hazard Control in Tunnelling and Underground Engineering

基　　金：国家自然科学基金资助项目(52109132);山东省自然科学基金资助项目(ZR2020QE270)。

摘　　要：为探究赋存断层岩体中隧道结构变形破坏基本特征,基于离散元理论,以断层位置、断层与隧道中心的法向距离、断层倾角及围岩等级为设计因素,采用UDEC程序开展地震波作用下跨断层深埋隧道结构动力响应数值模型试验。结果表明:地震波作用下不管隧道位于断层上盘还是下盘,衬砌结构均呈现出由椭圆型变形向扭曲变形转变的变形特征,围岩以剪切破坏为主,靠近断层一侧岩体塑性区向断层处延伸;断层穿过隧道中心时在地震波扰动作用下活化,衬砌最终呈现剪切变形特征,围岩塑性区沿断层面延伸;断层倾角和围岩等级保持不变时,断层与隧道中心的法向距离越大越有利于围岩-隧道结构的安全;断层与隧道中心的法向距离和围岩等级保持不变时,围岩塑性区面积随断层倾角增加呈现先减小后增大的变化趋势,而衬砌最大残余位移则表现先增大后减小的变化趋势;法向距离和断层倾角保持固定时,对于Ⅲ级围岩,衬砌未表现明显的椭圆型变形特征(接近圆形),围岩塑性区面积相比于Ⅳ级围岩显著减少;对于Ⅴ级围岩,断层对隧道影响不明显,衬砌最终呈现收敛变形特征。Dynamic response of deep buried tunnel structure crossing fault under the action of seismic waves was numerically analyzed based on the discrete element theory to explore the fundamental deformation and failure characteristic of tunnels.The simulation tests took fault location,normal distance between fault and tunnel center,fault dip angle and surrounding rock grade as design factors.All the lining structures showed deformation characteristics from elliptic mode to twisted mode under seismic waves with regardless of the spatial relation of the tunnel and fault.The surrounding rock mainly failed in shear and the plastic zone of the rock mass near the fault extended to the fault.When the fault passing through the center of the tunnel,the lining deformed in shear due to the seismic induced activation of the fault,and the plastic zone of surrounding rock extended along the fault plane.With the constant fault dip angle and surrounding rock grade,the greater the normal distance between the fault and tunnel was,the safer the tunnel was.With the constant normal distance and surrounding rock grade,the plastic zone area of surrounding rock decreased first and then increased with the increase of fault dip angle,vice versus for the maximum residual displacement of lining.When the surrounding rock grade was Ⅲ,the lining showed roughly circular deformation characteristic instead of obvious elliptic deformation and the plastic zone area of the surrounding rock was significantly reduced comparing to that of grade Ⅳ surrounding rock.When the surrounding rock grade wasⅤ,the fault influence on the tunnel deformation was not obvious,and the lining finally showed convergent deformation characteristic.

关 键 词：地震波 断层 隧道衬砌 变形破坏特征 

分 类 号：U45[建筑科学—桥梁与隧道工程]