Dynamic response of slopes under earthquakes and influence of ground motion parameters

A dynamic numerical simulation model of soil slopes was established with FLAC3D program,and the validity of simulation was validated with a shaking table model test.Based on this,the dynamic response laws and the influence of parameters of ground motion on the responses under earthquakes were analyzed.It was shown that the input seismic waves were affected by vertical and surface amplification of the slopes,and the effect amplified the input seismic waves with low frequency and filtered those with high frequency.It was reported that the coefficients of amplification of PGA along the slope surface decreased with the increase of amplitudes and frequencies of earthquakes,while these coefficients were less affected by the duration.It was also indicated that the maximum displacement of the slopes evidently increased with increase of amplitudes and duration of earthquakes while decreased with increase of frequencies.Furthermore,it was shown by the location and the shape of the maximum shear-strain increment region that the failure pattern of homogeneous soil slopes under earthquakes is instability along a potential sliding surface,similar to that under static condition.The results were helpful to further researches on the mechanism of slope instability under earthquakes.