地震作用下岩质边坡的动力破坏过程及破坏机制分析

Analysis of Dynamic Failure Process and Failure Mechanism of Rock Slope Under Earthquake

文中利用FLAC3D的动力分析模块,以ELCentro地震波水平动力荷载作为动力源,考虑了拉破坏对岩质边坡破坏的影响,研究在地震作用下岩质边坡的动力破坏过程、坡面处加速度放大系数及地震峰值水平加速度与破坏深度之间的关系。结果表明,在地震作用下,岩质边坡的破坏不是单纯的剪破坏,而是由坡顶的拉破坏和坡脚的剪破坏逐渐形成贯通面而导致的,且坡面顶部加速度放大系数大于坡面中部加速度放大系数,并大于坡面下部加速度放大系数,表现出明显的“鞭鞘效应”,同时随着地震峰值水平加速度的增加,边坡破坏面逐渐加深。

The impact and damage of earthquakes on slopes cannot be ignored.In this paper,the dynamic failure process of the rock slope,the acceleration amplification coefficient at the slope surface,the horizontal acceleration acceleration of the peak earthquake and the failure depth are studied by using the dynamic analysis module of FLAC3D as the power source,considering the influence of tensile failure on the failure of the rock slope.The results show that under the action of earthquake,the failure of rock slope is not a simple shear failure,but is caused by the tensile failure at the top of the slope and the shear failure at the foot of the slope gradually forming a penetrating surface,and the acceleration amplification coefficient of the top of the slope>the acceleration amplification coefficient of the middle of the slope surface>the acceleration amplification coefficient of the lower part of the slope surface show an obvious"whiplash effect",and the slope failure surface gradually deep-ens with the increase of the horizontal acceleration of the peak earthquake.