Abstract: Large shaking table model tests were conducted to investigate the seismic response of low-angle soil slope in permafrost regions, main influencing factors and the evolution process of the landslide subjected to vertical and horizontal seismic loadings, respectively. When shaking table tests were conducted on the 8°low-angle slope, the horizontal natural frequency of vibration decreased sharply at the failure state, however there was no apparent change in the vertical direction. The failure of slope model was characterised by completely slipping along the interface between the unfrozen soil and ice layer, while the deformation of soil was not observed inside the sliding body. The amplification coefficients of peak ground acceleration (PGA) increased with the elevation of the slope. Compared with little change of amplification coefficients before sliding, more obvious changes occurred along the surface of the slope after sliding. The peak amplification coefficient subjected to the horizontal seismic loading was greater than that subjected to the vertical one. The peak amplification coefficient in the soil-ice interface was obviously lower than that in the upper soil and lower ice layer. The pore water pressure in the soil-ice interface of the slope increased when the input acceleration reached a specific value. The weak soil-ice interface and the increasing pore water pressure were the main internal factors inducing the permafrost landslide subjected to seismic loading.

Key words: Qinghai-Tibet Plateau, permafrost, low-angle soil slope, landslide mechanism, shaking table, model test