穿越断层的隧道工程在中国高烈度地震区域已经较为普遍.针对这一问题,通过振动台模型试验研究在地震作用下减震缝、内外套管结构与不设防三种隧道结构的动力响应特征与破坏形式.通过对比在水平向地震作用下的峰值加速度与截面内力,可以看出:(1)减震缝显著降低穿越断层区结构截面内力,但结构水平加速度峰值较不设防区域则略微放大,进而有可能产生相对错动;(2)内外套管系统在穿越断层区域时,全设防区域的水平峰值加速度均有所降低,其外套管隧道在地震作用下截面受力与不设防隧道相似,进而发生破坏,但内套管隧道结构则拥有很高的生存率,保障隧道结构在大震过后仍能较好通行.为今后新型隧道抗震结构提出了设计参考.%Fault-crossing tunnels in high intensity earthquake zone are widely constructed in China.To improve existing aseismic design,shaking table tests on unprotected linings,the aseismic joint and the doubled-lining structure were conducted to study their dynamic responses and destructive patterns in earthquake.The comparison of the section internal force and maximum acceleration under the action of horizontal earthquakes shows the following results.(1) Aseismic joints dramatically reduced section internal forces of the fault-crossing structure while slightly enlarging the horizontal maximum acceleration of the structure,compared with the unprotected area,which may lead to relative dislocation.(2) When the doubled layer lining structure crosses the faults,the horizontal maximum acceleration of the fully protected area is reduced.The internal force on the cross section of the outer linings under the action of the earthquake is similar to an unprotected tunnel and damage occurs as a result.But the inner linings have high survivability,which enable fully functional service of the tunnel after the tunnel is stricken by a high intensity earthquake.Design references are given for the new seismic structure of tunnles in the future.
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