地震作用下含小净距隧道软弱围岩边坡动力特性研究

Study on dynamic response characteristics of slope with small spacing tunnel under seismic action

为了了解含小净距隧道边坡在地震作用下的动力响应特性,采用有限元分析软件Midas NX建立分析模型,并通过振动台试验验证.结果表明:地震波激振下,水平和竖直加速度放大系数随坡高增大均出现先减后增的变化趋势;不同类型的软弱围岩分界面处水平加速度放大系数出现较大增长;坡顶附近加速度放大系数急剧增大;坡脚附近的竖直加速度放大系数比水平加速度放大系数大.

In order to realize the dynamic response characteristics of slope with small spacing tunnel under seismic action, a dynamic numerical simulation model is established by using the Midas NX finite element numerical simulation software. And the validity of simulation is validated with a shaking table model test. The results show that under the excitation of seismic waves, the horizontal amplification coefficient and vertical acceleration amplification coefficient both increase first and then increase with the increase of slope height. The horizontal acceleration amplification coefficient increases greatly at the interface of different weak surrounding rock. Near the top of the slope, the acceleration amplification coefficient increases sharply. Near the foot of the slope, the vertical acceleration amplification coefficient is larger than the horizontal acceleration amplification coefficient.