IMPROVEMENT OF EVALUATION FORMULA FOR AMPLIFICATION FACTOR CONSIDERING DEPENDENCY OF EARTHQUAKE MAGNITUDE AND COMPARISON WITH OBSERVED VALUE

Abstract

We derived a relationship between source, site amplification spectrum and amplification factor, a formula to evaluate an amplification factor is proposed based on the relationship. In this study, we improve the formula by revising site amplification spectrum. A relationship between amplification factors calculated by the formula and moment magnitude Mw are examined, it found that amplification factors for PGV vary greatly according to Mw. The calculated amplification factors are compared with the observed value evaluated by multiple reflection theory. As a result, if site amplification spectrum is fit for theoretical spectrum, the calculated amplification factors for PGV are in good agreement with observed value.