EVALUATION OF GROUND MOTION AMPLIFICATION FACTOR CONSIDERING THE SHEAR STRENGTH OF SURFACE GROUND AND THE PEAK VALUE OF EARTHQUAKE MOTION ON THE BASEMENT

Abstract

 We propose the evaluation method of ground motion amplification factor considering the shear strength of surface ground and the peak value of earthquake motion on the basement. When the amplification factor of ground motion is evaluated, it is common to use such input parameters as the peak value of earthquake motion on the basement (PBA, PBV) and natural period of surface ground (T_g). In this research, the amplification factor can be evaluated by considering the degree of the ground nonlinearity expressed by the shear strength index of surface ground (K_f). In proposed method, the ground motion amplification factor can be evaluated by the same procedure as the conventional method. And the additional parameter required for the application of proposed method is only the parameter K_f. It is examined that the accuracy of ground motion estimation is improved by proposed method. If there is not the detailed soil investigations at site, K_f can be estimated by the simplified method which has been already proposed in past study. So, proposed method can be widely applied regardless of the amount of soil information at site.