蠕滑-强震叠加作用下跨断层隧道动力响应分析研究  

Dynamic Response Analysis on a Cross-Fault Tunnel Subjected to Action of Strong Earthquake After Fault Creep-slip

作　　者：陈峻博 王天强 耿萍[1] 孟庆余 霍飞 王旭 CHEN Junbo;WANG Tianqiang;GENG Ping;MENG Qingyu;HUO Fei;WANG Xu(Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,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,成都610031 [2]中国铁路设计集团有限公司,天津300308

出　　处：《铁道标准设计》2025年第1期129-138,共10页Railway Standard Design

基　　金：国家自然科学基金项目(52130808);国家重点研发计划政府间国际科技创新合作重点专项课题(2022YFE0104300);中国国家铁路集团有限公司科技研究开发计划项目(K2020G033)。

摘　　要：处于高烈度地震区的跨断层隧道在遭受断层蠕滑作用威胁的同时,强地震动对隧道的安全运营提出更为严苛的要求。鉴于此,为研究蠕滑-地震作用对跨断层隧道的影响,以汕头湾海底隧道穿越活动断裂带为背景,结合实际工程场地特征及地震动参数,确定了隧址区断层百年蠕滑错动量。考虑衬砌结构的非线性塑性损伤特性,建立蠕滑-强震叠加作用的三维数值计算模型,开展隧道在断层蠕滑导致的初始损伤下的结构动力响应分析研究,得出以下结论。(1)当仅受断层蠕滑作用时,隧道的显著相对变形发生在断层破碎带附近;隧道拱顶及拱底位置的拉压效应较为显著,且表现出明显的受剪切状态。(2)叠加地震作用后,断层带附近隧道的加速度放大现象较为显著,最大放大系数为3.0。(3)叠加地震动作用后,隧道的横向变形和拱腰应变较断层蠕滑单独作用时的隧道响应显著增大。最大水平相对位移增加至2.90 cm,等效塑性应变放大5倍。(4)断层蠕滑作用下隧道的损伤集中在断层面处,而地震动作用将加剧这种破坏,并导致隧道拱肩和拱脚的累积损伤。(5)蠕滑错动后的地震动作用放大了隧道的损伤响应,更大的初始蠕滑错动量导致更严重的损伤量级,更大的PGA则导致更广范围的损伤。相较于无蠕滑损伤的隧道,蠕滑-地震作用下隧道的拉伸损伤衬砌体积可增加224.8%。研究结果可为我国高烈度地震区跨断层隧道的抗震性能设计提供参考。While fault creep-slip poses a risk to cross-fault tunnels in seismically active regions,intense ground shaking will impose more rigorous requirements on the safe functioning of the tunnel.Thus,the 100-year creep-slip dislocation of faults in the tunnel site area is calculated based on the Shantou Bay subsea tunnel,which crosses the active fault zone and is taken as the background and combining the actual engineering site characteristics and ground vibration parameters.A three-dimensional numerical calculation model of creep-slip-earthquake is established by taking into account the nonlinear plastic damage properties of the lining structure,and a study on the structural dynamic response of the tunnel to the initial damage caused by creep-slip of the fault is conducted.The results show that:(1)The tunnel has significant relative deformation near the fault fracture zone when it is only subjected to fault creep;the tensile and compressive impacts are more evident at the tunnel crown and invert,and the tunnel shows obvious shear state.(2)After the earthquake,the acceleration amplification phenomenon of the tunnel close to the fault zone becomes increasingly significant,with a maximum amplification factor of 3.0.(3)The horizontal deformation and arch waist strains of the tunnel following the ground shaking are significantly higher than the tunnel response under the single action of the superimposed ground slip.Maximum horizontal relative displacement is increased to 2.90 cm,and the equivalent plastic strain is multiplied up to five times.(4)The tunnel under the fault creep-lip damage is confined at the fault plane,and the ground shaking action amplifies the damage,resulting in cumulative damages to the tunnel arch foot and shoulder.(5)With greater initial creep-slip dislocations causing more severe damage magnitudes and larger PGA causing a wider range of damage,the effect of ground shaking following creep-slip dislocation enhances the tunnel damage response.The tensile damage lining volume of the tunnel under creep-s

关 键 词：跨断层隧道 断层蠕滑 地震动作用 数值模拟 结构响应分析 初始损伤 损伤演化 

分 类 号：U25[交通运输工程—道路与铁道工程] U45[建筑科学—桥梁与隧道工程]