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On December 18, 2023, the Jishishan M(S)6.2 earthquake caused serious damage to Jishixiongguan, China, which is a rammed-earth city wall, and was about 14 km away from the epicenter. There was a large area of collapse and part of the vertical ramming overlap separation phenomenon. Based on the results of earthquake field investigation, the dynamic response of Jishixiongguan under the earthquake was studied by analyzing the maximum displacement, peak acceleration (PA) and stress-strain distribution characteristics of wall measuring points at different locations, and the mechanism of Jishixiongguan failure induced by Jishishan M(S)6.2 earthquake was given. The results show that the plastic zone initially develops from the bottom erosion of the wall and the transverse through crack at the top of the right-end, and it rapidly extends downward along the slope into the interior of the wall, resulting in destructive permanent displacement shortly after the peak ground acceleration (PGA) is reached, the maximum plastic strain and maximum displacement occur at transverse through cracks of the right-wall top. Owing to the wall being constructed against a mountain slope, the amplification effect (AE) of the slope on the displacement of the wall is obvious, and the closer the wall is to the higher parts of the slope, the more significant the AE of the displacement is due to the combined effect of the mountain slope and the wall height. Pre-existing defects in the wall will weaken the AE of the slope and the wall height on the acceleration, however, the transverse through cracks will enhance the AE of the wall height on the acceleration. Stress concentration caused by hollowed-out overhangs and stress discontinuity caused by the transverse through crack is the internal factor of the wall failure, the plastic yield of soil caused by the AE of slope and wall height on displacement is the external factor of large-scale collapse of wall. The research results can provide theoretical guidance for the restoration and reinforcement of ancient sites.

来源平台：SHOCK AND VIBRATION