Evaluating proxy-based site response in Israel

Three alternative site-response models are developed, using two complementing predictors, accounting for both stiffness and depth effects. The analysis is based on a large database of velocity profiles and their associated calculated amplifications with respect to the local generic rock profile. The frequency of peak amplification—f_peak —is chosen to supplement V_S30, after considering the predictability of eight different site proxies. The suggested models are continuous in terms of spectral periods as well as in terms of their predictor parameters—V_S30 and f_peak. Model performance is evaluated in terms of the reduction in variability. For example, for a spectral period of T 0:5 s, using either one of the suggested models reduces the amplification variability from 0.4 to 0.18, whereas using V_S30 alone reduces it only to 0.24. This improvement suggests that the addition of f_peak is a significant improvement in the midperiod range.