The Urban Rain-flood Risk Division Based on the Cloud Model and the Entropy Evaluation Method-Taking Changzhou as an Example

In order to improve cities' non-engineering measure capacity to cope with rain-flood disasters and provide emphasis for government's flood protection, the urban rain-flood risk division was studied. The cloud model can be used to deal with qualitative and quantitative transformation and adapt to randomness and fuzziness of urban rain-flood risk evaluation. By taking Changzhou as a research object, 3 criterion layers, including hazard inducting environment, hazard-affected body and disaster-inducing factors and 11 indexes were selected. The cloud model and entropy evaluation method were chosen to evaluate the urban rain-flood risks. Besides, ArcGIS software was used to draw the urban rain-flood risk division map of Changzhou. The findings showed that regions with the higher rain-flood risk grade included most of areas in Jintan District and Xinbei District, some areas in Wujin District and Zhonglou District. The corresponding flood protection measures should be taken.