STUDY OF INUNDATION AND EVACUATION ANALYSIS IN UNDERGROUND MALL FOCUSED ON DIFFERENCE OF RAINFALL PATTERNS

Abstract

 In recent years, the frequency and amount of short duration torrential rains have been increasing due to the climate change. When torrential rains occur in urban areas, these areas hold the possibility of being inundated not only above the ground but also underground. In this study, the risk of the mega underground space in Osaka was evaluated by analyzing the inundation of aboveground and underground spaces in the event of pluvial flooding caused by assumed maximum rainfall, and it was analyzed how the difference of rainfall patterns affects the safe evacuation from underground spaces. In addition, it was also examined if installing flood boards at the entrances of the underground space with early inflow improve the success rate of evacuation. The analysis results show that the evacuation success rate varies with the rainfall patterns and that the evacuation success rate improves even when flood boards are installed only at the entrances which floodwaters flow in quickly.