Conversion of building structures to an incombustible state is one of the most important issues in the field of disaster prevention planning. In Tokyo metropolitan area, it is a great concern to improve the incombustibility of cities since a devastating earthquake and subsequent fire would cause the wide spread damages. In this study, we construct a probabilistic model, which describes the conversion process of building structures. By using this model, we estimate the time-series changes of the building structures in an established city area and extract some hazardous areas from the viewpoint of disaster prevention. In the areas, we simulate the time-series changes of the building structures by applying some urban regulations and evaluate how much those regulations are effective and efficient for promoting the incombustibility of the areas.
