Abstract: Dynamic finite element numerical simulation is commonly used in the seismic design for high slopes. However,linear-elastic methods will cause big errors when the slope rock displays plastic behavior and the deformation develops under earthquake action. In view of this,elastoplastic method is adopted to calculate the seismic response of elastoplastic slope in the full equilibrium of both static and seismic motion,trying to explore the dynamic state of rock slope elastoplasticity. Two seismic waves with the same peak acceleration but different periods and durations were input. The peak accelerations of seismic motion parameters and the mechanism of seismic response for accumulative plastic strain,both widely used in seismic design,were analyzed in consideration of the natural frequency of slope. Result shows that the seismic accumulative plastic strains are distinct when inputting seismic waves with the same peaks but different periods and durations; although the peaks are the same,the seismic effect varies given different durations and spectral characteristics. As a result,in the calculation for slope seismic design,the seismic wave should be chosen discreetly,varying from one case to another,otherwise it would cause unreal seismic safety evaluation result.

Key words: rock slope, seismic response, duration of seismic wave, accumulative plastic strain