Abstract
Prediction of the number of evacuees in an earthquake disaster is an important issue for post-disaster management. In this study, as a fundamental investigation, the initial number and its decreasing process of the evacuees in five municipalities damaged by the 2016 Kumamoto earthquake have been compiled on a daily basis in conjunction with building damage, blackout, suspension of water supply, aftershocks and supply of temporary housing. In addition to the population occupying houses completely or partially destructed and the population without electricity and/or water supply, the time function representing the degree of social resilience has been introduced in order to model the temporal change of the number of evacuees (model 1). In addition, the post-peak decreasing process of the number of evacuees has been modeled using a mixed exponential distribution composed of three kinds of exponential functions corresponding to the short-, medium- and long-term effects (model 2). The change of the number of evacuees have been characterized by the model coefficients.
