Hazard Assessment And Zoning Research Of Landslide In Shaanxi Province Based On GIS

Shaanxi Province is one of the provinces with the most serious geological disasters in China,especially the landslide geological disasters.The economic losses and adverse effects brought by the frequent occurrence of geological disasters in recent years have aroused widespread concern from all walks of life.Therefore,in order to protect people's life and property safety,reduce losses caused by disasters,and improve the efficiency of disaster prevention and mitigation work,it has important application value and practical significance for the study of hazard assessment of geological disasters.This paper takes Shaanxi Province as the research area,and analyzes the disaster-causing factors of the most widespread landslide disasters based on GIS and historical disaster data.Through the classification and correlation of various index factors,a landslide hazard evaluation index system was established.Then using data-driven statistical analysis model to study the hazard assessment of landslides in the study area.Main results of this thesis are as follows:(1)This research will study and analyze the development types and distribution characteristics of landslide disasters in Shaanxi Province.The results show that the occurrence of landslide geological disasters in the study area is mainly affected by control factors and inducing factors.The landslide disasters in the area mainly occur in the low mountains and Zhongshan areas of southern Shaanxi,and are consistent with the distribution of faults and water systems.In addition,frequent human engineering construction activities have caused the destruction of the original geological environment,heavy rainfall and continuous rainfall can easily induce landslide disasters.(2)Based on the landslide proportion,grading ratio and information value under various indicators of landslide hazard,selected 9 factors to establish a hazard assessment index system for the landslide hazard in the study area,including the elevation,slope,aspect,geotechnical type,distance from the fault zone,distance from the water system,peak acceleration of ground motion,annual average rainfall,and distance from the traffic line.(3)Based on GIS and data-driven evaluation model(information model,deterministic coefficient model,logistic regression model and their combined model),the hazardassessment of landslide in the study area was carried out.According to the evaluation of the partition and accuracy test results of each model,the I+LR model is determined as the optimal model for this study,and the results of the evaluation zoning are in good agreement with the distribution of historical landslide disasters.The high risk area of the landslide accounts for21.86% of the area of the study area,and the distribution ratio of the landslide disaster is84.65%.The high-risk areas of landslides are concentrated in the Qinba Mountains in southern Shaanxi,and the closer to the river,the tectonic belts,and the areas on both sides of the traffic line,the higher the risk of landslide hazard.(4)The results show that the application of data-driven statistical analysis model in the provincial large-scale landslide hazard evaluation is highly accurate and reliable.In addition,compared to the single model quantitative evaluation,such as information model,the deterministic coefficient model,logistic regression model,the combination model of information-based logistic regression model and logistic regression model based on deterministic coefficient has higher evaluation accuracy because the weight information of each index factor is considered.