Dynamic evolution mechanism of a rock slope with discontinuities under earthquake motions using shaking table tests

Under the impact of earthquake, even if the slopes do not fail, the integrity of rock slope structure would be damaged subjected to the seismic motion. The process of damage, destruction and failure for slopes is characterized by the dynamic evolution of stability. In the areas with active tectonic activities, frequent earthquakes have a significant effect on the attenuation of slope stability. To investigate the dynamic evolution of a rock slope under earthquake motions, a series of shaking table tests were performed. An artificial synthetic earthquake seismic wave was adopted to investigate the horizontal acceleration response. The results show that the wave field propagation results in acceleration amplification for the slope body above the tuff structural surface are larger than those inside the slope, and a maximum value of 3.7 is observed at slope crest. The structural surface results in a mutation of the acceleration response, which is not conducive to the slope stability. The modeled slope entered the plastic stage (input motion of 2.97 m/s2) earlier than landslides occurred (input motion of 4.46 m/s2). In addition, the safety factor of the sliding blocks was calculated based on pseudo static analysis. A good correspondence was found between the safety factors and the failure mode of the slope. The damage evolution process for the rock slope can be divided into three stages: an elastic stage (1.6 < safety factor ≤ 4.7), a plastic stage (0.8 < safety factor ≤ 1.6), and a damage stage (safety factor ≤ 0.8).