Evaluation of site amplification factors at severely damaged sites during the 1923 Kanto Earthquake by using the EMR and VACF methods

抄録

The 1923 Kanto earthquake has not been sufficiently verified with respect to the strong ground motion generation areas with a period of less than 2 seconds, which is directly related to building damage. With the goal of determining the source rupture process by targeting the building collapse ratio, we first estimated the site amplification factors in the heavily damaged areas using the EMR method proposed by Kawase et al. (2018) and the VACF method by Ito et al. (2020). At sites with an observed collapse ratio of 100%, the amplification factor is large around a period of 1 second, and the site amplification factors may explain the occurrence of major damage, although the contribution of the source characteristic must also be taken into account. On the other hand, there are some sites where the site amplification is small but the damage is relatively large. In such municipalities, it is considered necessary to explain the damage exclusively by the source.