Dynamic stability assessment of consequent rock slopes considering multiple transmissions and reflections of stress waves

Abstract

In this work, Based on the conservation of momentum at the wave fronts and the displacement discontinuity method, a theoretical approach for calculating the dynamic safety factor of consequent rock slopes is proposed. The multiple transmissions and reflections of stress waves on the joints and free surfaces are taken into account. A comparison of UDEC simulation and theoretical calculation was carried out to verify the feasibility of the proposed method. Moreover, parametric studies were conducted to investigate the effects of free surfaces, joint stiffness, amplitude of incident waves, and frequency of incident waves. The results show that the proposed method can predict the time history curve of the safety factor of a slope readily and accurately. Waves reflected from both the slope and top surfaces are found to have a significant effect on the stability of the slope – considering them or not can cause a difference in the safety factors up to 32.5%. The greater the joint stiffness is, the greater the safety factor fluctuates with time. However, when the joint stiffness is sufficiently high, the effect of joint stiffness on the safety factor can be neglected. The approach proposed in this work provides a theoretical tool for the dynamic assessment and design of consequent rock slopes. Highlights An analytical method is proposed for calculating the dynamic safety factor of rock slopes. Multiple transmissions and reflections of stress waves are considered. The proposed method has high calculation accuracy and can be applied in practice.