抛石防波堤地震反应的颗粒流数值模拟

Particle Flow Numerical Simulation of Seismic Response of Rubble-mound Breakwater

基于颗粒流离散元法,对地震动作用下抛石防波堤的动力响应进行了数值模拟分析,结果表明:地震动作用下的抛石防波堤变形规律与经典破坏模式吻合;颗粒粒径相同时,输入峰值加速度越大,坡顶的沉降量越大;相同输入地震动条件下,颗粒粒径越大,坡顶沉降量越小;颗粒粒径和输入峰值加速度相同时,水平和竖向组合输入引起的坡顶沉降最大,单一水平向输入次之,单一竖向输入最小;峰值加速度放大系数随输入峰值加速度的增大逐渐减小;颗粒粒径越大,峰值加速度放大系数越大;抛石防波堤变形特征表现为坡顶沉降,坡体两侧斜向下滑移,坡面存在浅层滑动。研究方法及结果可为抛石防波堤抗震设防提供参考依据。

Based on the particle flow discrete element method,we numerically simulated and analyzed the dynamic response of rubble breakwater,triggered by the earthquake ground motion.It is found that the deformation law of rubble-mound breakwater is consistent with the classical failure mode of it.The particle size of rubble-mound breakwater being the same,the larger the input peak acceleration is,the larger the final settlement of the rubble-mound breakwater top is.Under the same input ground motion,the larger the particle size is,the smaller the slope top settlement is.When the particle size and the input peak acceleration are the same,the settlement of the rubble-mound breakwater top caused byinput combining both horizontal and vertical component is the largest,followed by horizontal input,and the vertical input is the smallest.The magnification coefficient of peak acceleration decreases gradually with the increase of input peak acceleration.The larger the particle size is,the larger the magnification coefficient of peak acceleration is.The deformation of rubble-mound breakwater is characterized by settlement at the top,oblique displacement at both sides of the slope,and shallow sliding on the slope surface.The research method and results can provide some reference for seismic protection of rubble breakwater.