Three-dimensional discrete element simulation of the amplification effect of the slope surface under the action of strong earthquakes

Abstract

To study the dynamic amplification effect of slope surfaces under the action of strong earthquakes, a three-dimensional model was established using a rocky slope in Mian County, Shaanxi Province, as an example. The discrete element software 3DEC is used to simulate the deformation and instability process of the slope under dynamic conditions, analyse the dynamic response characteristics of the slope surface, and study the difference in the dynamic response of the slope surface under different seismic wave input conditions. The main conclusions are that when considering the influence of seismic longitudinal waves, the vertical acceleration is significantly enhanced, and the PGA amplification factor of the slope is increased by approximately 1.62 times. The slope shape strongly affects the dynamic response characteristics of the slope surface. Under the action of strong earthquakes, the amplification of the slope shoulder and the slope turning point is very strong, followed by the protruding parts, and the amplification on both sides of the slope surface is the weakest. Under different input conditions, the horizontal PGA amplification factor at the slope turning point maintains a high value, especially when only the horizontal acceleration is input, and this part should be given special attention in the prevention of earthquake landslide disasters. The movement process of a landslide caused by strong earthquakes can be summarized as the initiation stage of the landslide-the high-speed movement stage of the squeeze collision-the accumulation stage. The research results can provide certain theoretical support for disaster prevention and mitigation in this region.

Keywords

• strong earthquakes
• 3dec
• rock slope
• dynamic response
• amplification of surface