Dynamic response of high and thin rock slope under blasting vibration: a case study

The topography of a thin double-sided rock slope differs greatly from that of a regularly studied single-sided rock slope, which leads to difficulties in investigating the dynamic response of the thin double-sided rock slope. Through a case study, this paper provides a specific prospect on the dynamic response of the high and thin rock slope under blasting vibration. The high and thin rock slope belonging to Chiwan Mountain was selected as the typical case slope. Field monitoring programs for blasting vibration on the case slope were carried out using vibration monitoring systems. The amplitude, frequency, and energy characteristics of the recorded blasting vibration were then concretely identified and examined. The monitoring results were further used to validate the dynamic finite element model developed to explore the effects of blasting vibration frequency and amplitude on the dynamic response of the slope. The dynamic finite element model of the case slope subjected to blasting vibration was established using the software LS-DYNA. According to the monitoring and numerical results, the dynamic response mechanism of the high and thin rock slope under blasting vibration was discussed. The results indicate that the elevation amplification effect of blasting vibration exists on the southern slope from a certain elevation, and the dominant frequencies generally decay with the distance from the blasting source but remain largely the same within a specific elevation range. The blasting vibration frequencies have considerable influence on both the values and distributions of peak particle velocities on the slope while the blasting vibration amplitudes have an impact only on the values of peak particle velocities. The dynamic response of the case slope under blasting vibration results from the joint effects of blasting seismic wave propagation and structural resonance. The research findings may pave an effective way to clearly understand the dynamic response of similar high and thin rock slopes under blasting vibration.