Probability Identification And Prediction Of Potential Landslide Hazard Area In Sichuan-tibet Traffic Corridor Based On Slope Unit

To identify the danger zone of landslide hazard along the line of linear engineering scientifically can make the route avoid the danger zone of landslide as far as possible and take preventive measures in advance,so as to reduce the disaster loss and take active prevention.The landslide hazard in the section of Sichuan-Tibet traffic corridor from Bangda airport to Ranwu is very developed,which has a great potential safety hazard to the national highway 318 road project and the Sichuan-Tibet railway project with this section as the preferred route.In this paper,the section from Bangda airport to Ranwu of the Sichuan-Tibet traffic corridor is taken as the research area,the slope unit divided by hydrologic analysis method and surface curvature watershed method are the basic analysis units,and the frequency ratio method is used to identify the static probability of the potential landslide hazard area in the study area.Based on the TRIGRS physical mechanics model and Rosenblueth point estimation method,the dynamic probability identification model of the potential landslide hazard area was established,and the dynamic prediction of the potential landslide hazard area under the condition of dynamic rainfall duration at different recurrence periods in the study area were carried out.The main results show that:(1)The basic characteristics of the static hazard of landslide in the study area are as follows: the former section of the line from Bangda airport to Nujiang river is mainly a low-hazard area and a medium-hazard area,the former section from Nujiang river to Basu and the former section from Basu to Langzong are mainly a high-hazard and extremely high-hazard area,and the former section from Langzong to Ranwu is mainly a low-hazard area.The results of static hazard zoning of landslide are basically consistent with the distribution characteristics of actual landslide hazards.(2)The basic characteristics of the probability of dynamic prediction of landslide disaster in the study area are as follows: from the section of Bangda airport to Ranwu,the hazard probability of slope increases first and then decreases gradually.In the case of once-in-100-years rainfall scenarios,22.76% of the regions are areas with high probability of instability.(3)The results of landslide hazard zoning by the statistical model and the physical model show that the probability of slope failure from the section of Bangda airport to Ranwu increases first and then decreases gradually,but there are differences,mainly reflected in the section of Lanzong to Ranwu.(4)The results of static identification and dynamic prediction both show that the curvature slope unit not only considers the inherent characteristics of the slope itself,but also divides the actual slope terrain more carefully and accurately,and its evaluation result is better.In the study of landslide hazard identification,the selection of a suitable basic evaluation unit has an important influence on the accuracy of the results.With the slope unit as the basic unit of analysis,this study of fastening the typical period of potential landslide in traffic corridor of danger accurate identification,and combined with the background of climate change conditions to dynamic prediction of landslide danger zone,not only for Sichuan-Tibet railway,Sichuan-Tibet highway engineering construction and later operation security provides important support of science and technology,and the development of the area planning and sustainable development has important practical significance.