FAILURE CHARACTERISTICS AND INFLUENCE FACTOR ANALYSIS OF MOUNTAIN TUNNELS AT EPICENTER ZONES OF GREAT WENCHUAN EARTHQUAKE
FAILURE CHARACTERISTICS AND INFLUENCE FACTOR ANALYSIS OF MOUNTAIN TUNNELS AT EPICENTER ZONES OF GREAT WENCHUAN EARTHQUAKE
复制标题
DOI：
--
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
Liu Tianbin
中科院分区：
文献类型：
--
作者：
Liu Tianbin
2008年5月12日，四川省西部龙门山断裂带发生了8.0级汶川特大地震，都江堰至汶川高速公路上的多座隧道因地处震中附近而遭到严重破坏。 进一步总结了隧道洞口崩塌滑移、洞口裂隙、衬砌及围岩崩塌、衬砌开裂错位、拱顶抬升开裂、初步支撑变形开裂等基本类型，并重点考虑隧道次生断裂的控制作用，探讨了隧道震害的影响因素。 最后根据汶川地震山岭隧道破坏的自然结果，总结了隧道抗震的一些启示，建议在强震地区进行综合抗震设计。 将掌子面边坡、裸露隧道和隧道洞口结构作为一个系统考虑。对于穿越活动裂隙次生断层的隧道，沿断层及其两侧一定距离二次衬砌宜采用钢筋混凝土结构。对于覆盖层与基岩接触带、软硬岩体变化带、围岩质量跃变带等应采用以下方法处理： 提高其力学性能，使其在初步支撑中逐渐变化。
The great Wenchuan Earthquake of Ms 8.0 grade took place in the Longmenshan fault zone of western Sichuan Province on May 12,2008.Many tunnels on the highway from Dujiangyan to Wenchuan were damaged severely due to the site located near the epicenter.Through the on-site investigation and research,the data collection and analysis,this paper illustrates the failure types and characteristics of the mountain tunnels in the severe earthquake region.It further summarizes the basic types as the avalanche and sliding of tunnel opening,the rhegma of tunnel portal,the collapse of liner and surrounding rock,the crack and dislocation of liner,the uplift and crack of arch invert,the deformation and crack of preliminary bracing.Then,the influencing factors of the tunnel seismic damages are discussed by taking into account especially the controlling functions of the secondary faults of earthquake fractures,the contact zone between cover and bedrock,the unstable slope in the tunnel face,and the weak surrounding rock in high geostress environment on the strong seismic damages.Finally,some revelations of the tunnel earthquake-resistance are summarized based on the natural results of the mountain tunnel damages in Wenchuan Earthquake.It is suggested that in strong earthquake areas,a comprehensive aseismic design be conducted considering the slope of tunnel face,naked tunnel and tunnel portal structure as a system.For tunnel crossing the secondary faults of active fractures,the reinforced concrete structure should be used in the second lining along the faults and their bilateral some distances.For the contact zones between cover and bedrock,the change zones between weak and hard rockmasses,the jump zones of surrounding rock quality and so on,they should be treated by the methods of improving their mechanical property and making it gradual change in preliminary bracing.