隧道地震响应简化分析与动力离心试验验证

 基于平面应变和拟静力假定，采用弹性理论方法，推导出动荷载作用下圆形隧道外围的土体弹簧系数以及土层剪切应力表达式，将其运用于响应位移法分析隧道的地震响应，对该方法做进一步简化与完善；进行隧道响应的动力离心机模型试验研究，将试验结果与改进后的简化分析结果对比，验证该方法的可行性与合理性；通过离心试验的应变测量，以最直观的方式对比隧道在静力和动力荷载作用下受力状态，研究结果表明，隧道和地基土的地震响应与地震强度和边界条件密切相关，隧道地震响应特征与静力状态存在明显差异。研究结果可为隧道抗震设计提供参考。

SIMPLIFIED ANALYSIS OF TUNNEL EARTHQUAKE RESPONSE AND CENTRIFUGE MODELLING CALIBRATION

Based on plane strain and quasi-static assumption,by using elasticity theory method,the soil-spring coefficient and shear stress expression of stratum around a circular tunnel under dynamic load are derived. These are introduced into the response-displacement method to evaluate tunnel responses;and this method is further simplified and improved. To validate the revised approach,centrifugal tests are performed. The comparison between test result and analysis result by simplified and improved method is made;and it is proved that the revised simplified solution is feasible and practical. Meanwhile,the tunnel strains are observed,and the stress states under different force conditions(static and dynamic) are compared intuitively. The results indicate that the dynamic responses of tunnel are significantly different from those under static condition;and the performance of ground and tunnel depends on earthquake intensity and boundary conditions closely. The study results can provide a reference to earthquake resistance design of tunnel.