Geological Hazard Risk Assessment In Diversion Channel Of Baoding Section Of Middle Route Of South-to-North Water Transfer Project

The distribution of the diversion canal of Baoding section of the Middle Route Project of South-to-North Water Transfer is from Yanzhao Town,15 km southeast of Quyang County Town on the South side,to the northwest side of Dongchengfang Town,Zhuozhou City,to Beijing,which passing through nine counties or cities in Baoding area.Because located in the transition zone between the North China Plain and the Taihang Mountains,along which the regional geomorphology span is large,the geological background is complex,and the tectonic activity is strong,the diversion canal is threatened by various geological hazards.On the basis of collecting relevant data and carrying out field geological hazard investigation,this thesis uses support vector machine model to complete the geological hazard risk assessment in the study area.The main highlights of this thesis are as follows:(1)On the basis of summarizing the development and distribution characteristics of six types of geological hazards in the study area,all of them are divided into two types,and two evaluation systems are established for risk assessments and analysis of both types of geological hazards: The first type of landslide geological hazards is mainly distributed in mountain areas,including collapses,landslides and debris flows;The second type of ground fissures and other geological hazards is mainly distributed in the plain area,including ground fissures,ground subsidence and land subsidence.(2)This thesis expounds the practical significance and mathematical performance of the correlation between evaluation indicators in detail,and quantifies the evaluation indicators into independent lowdimensional and high-efficiency calculation indicators through CF-SO-PCA model.(3)In the process of building support vector machine model,typical disaster points and non-disaster points are selected as training and test samples to make the evaluation results closer to the actual situation;In order to achieve the highest prediction accuracy,cross validation method is used to search the best parameters of the support vector machine model.(4)Based on the risk mapping of geological hazards in the study area,the diversion canal of Baoding section of the middle route of South-to-North Water Transfer Project is divided into sections,and the key prevention and control types of geological hazards in each section are determined,which provides the basis for the prevention and control of geological hazards along the diversion canal of the Baoding section of the middle route of South-to-North Water Transfer Project.(5)FLO-2D was used to analyze the risk of typical debris flow ditches under different extreme frequency rainfall conditions,and the effects of potential debris flow on diversion canals,Beijing-Kunming Expressway and downstream villages are analyzed.