2017 Volume 30 Pages 43-51
When a large earthquake happens in major city, a great number of post-earthquake fires would occur and expand in densely wooden buildings built up area. Furthermore, it is estimated that the number of fires would exceed the number of the pumper trucks in the suffered area. And the pumper trucks would face to difficulty of forward movement to firing area because of many street blockades by building collapse. Therefore, aerial firefighting by helicopters is needed. This study aims to clarify the relation between the firing properties in a burning area and the dropping water by helicopters. According to the numerical experiments based on the fire engineering methods, it becomes clear that there is a close relationship between marginal distance of the spread between two buildings and frequency of dropping water by helicopters. In addition, we clarified the requirements of urban area where is more effective to drop water by helicopters.
