Prediction of soil factors by a non-parametric approach

Abstract

The problem addressed in this paper is the estimation of the (de)amplification of ground motion at soil sites (compared to rock sites) as a function of the intensity of ground motion. A non-parametric empirical approach, called the CAE (Conditional Average Estimator) method has been used. Soil factors (SFs) for peak ground acceleration and spectral accelerations were predicted by using combined PEER and European database of recorded ground motions. Comparisons were made with SFs used in codes (Eurocode 8 and ASCE 7-10), with SFs proposed by Huang-Whittaker-Luco, with SFs obtained from four NGA GMPEs, and the European Akkar-Bommer model. The study reveals that: (1) SFs depend strongly on the ground motion intensity. They depend also on the magnitude of the earthquake. (2) Existing models yield very different results for SFs. (3) SFs predicted in this study are, for higher intensities of ground motion, generally smaller than the existing ones