Evaluation Of The Collapse And Landslide Susceptibility In Bijie City,Guizhou Province

Because geological disaster has characteristic of suddenness,durative and cluster,it will lead a heavy impact of hazard on human life and safety.Therefore,the evaluation of geological disasters is particularly important and can provide important guidance for the development of disaster prevention and mitigation.In this paper,taking the area of Bijie City,Guizhou Province as an example,based on the analysis of regional geological background and summarizing the distribution law and control factors of geological disasters in the study area,the comprehensive application of multi-model calculation and multi-classification method comparison is adopted to select suitable for this area.The evaluation model and the grading method of collapse and landslide geological disasters have achieved the following results:(1)The main control factors for the single-collapse and landslide geological disasters is obtained in Bijie City.Through the analysis of typical disaster points,it is proposed that the impact factors of collapse and landslide geological disasters are high-steep terrain,development of steeply inclined structural planes,development of goaf activities,and concentrated rainfall.(2)The main controlling factors of regional collapse and landslide geological disasters is determined in Bijie City.On the basis of comparative analysis of the frequency ratio of each factor to the accuracy of susceptibility evaluation,the lithology,elevation and slope of the formation are determined as the main controlling factors of regional collapse and landslide geological disasters.(3)The optimal model for the evaluation of the geological disasters of collapse and landslides in Bijie City was constructed.Through the three evaluation models of analytic hierarchy process,frequency score and information model,the evaluation of the susceptibility of collapse and landslide geological disasters in Bijie City is carried out respectively,and the success rate of each model is verified by the success rate curve,and the information model is finally determined to be optimal.model.(4)The optimal grading method for the susceptibility to geological disasters in the collapse and landslides of Bijie City is proposed.Summarize the existing classification methods,which are natural fracture method,normalized classification method,and prone index area ratio classification method.The global susceptibility index calculated by the information model is graded by three models,and the spatial accuracy verification method(geological hazard frequency ratio)is used to determine that the natural fracture method is most suitable for the collapse of the Bijie City and the grading of landslide geological disasters.