| China is one of the countries that the debris flows break out frequently. Once breaking out, they will destroy the house, the road and the infrastructure dissolvingly, and cause huge loss to people’s lives and properties. Therefore, there is an urgent need for people to take measures for debris flow disasterprevention and reduction, and the priority is to cognize and evaluate the actuality andthe risk of the debris flow.This paper contains two main parts: the forecast of the debris flow’s danger zone, and the assessment of the debris flow’s danger level.Rely onthe project of satellite-based monitoring system developed geological hazard survey and demonstration applications, the paper extracts information from 9 relatively intact debris flow by means of homebred satellite data andthree-dimensional GIS technology in Songpan County,Sichuan Province, and then set up the model for debris flow’s danger zone forecasting. On this basis, this paper assesses the danger level of a typical debris flow. The distance to the debris flow ditch mouth is taken into account as an evaluation factor for the first time, and then it is graded according to the velocity decreasing coefficient. After that,the debris flow risk assessment system is established, and we get theresult of debris flow risk assessment eventually. Depending on all above studies, we getsomeachievements as following: 1.Thedebris flowsdistributing information was extracted from homebred satellite data, and then the reserves data of materialsource and the basin relief datawith high precision were got from 9 relatively intact debris flows. 2.The paper has set up the model for debris flow’s danger zone forecasting by multivariate nonlinear regression analysis between the danger zone and the factors. 3.The debris flow risk assessment system took the distance to the debris flow ditch mouth into account as an evaluation factor for the first time, and the factor was graded according to the velocity decreasing coefficient.Finally the study got the assessment result through indexes weighted arithmetic based on AHP method. |
