Geological Disaster Hazard Assessment Along The Sichuan-tibet Network Project Based On RS And GIS

With the continuous development of the national economy,China?s engineering construction has gradually developed towards the central and western regions.The frequent occurrence of various types of geological disasters in the southwest region has caused serious damage to the safety construction,operation and maintenance of the project,and it is necessary to carry out the research on the risk monitoring of geological disasters in construction projects.In addition to comprehensively analyzing the geological environmental conditions and natural environmental conditions of geological disasters,the research on geological hazards of infrastructure construction projects also need to consider the trigger conditions of geological disasters and realize the dynamic monitoring of geological hazards on the time scale,provide basis for disaster prevention of the project.The research on geological disaster risk monitoring of infrastructure construction projects needs to follow the general flow of regional geological disaster risk assessment,which needs to select the appropriate evaluation factors by data collection and analysis,and use some certain evaluation methods to complete the monitoring of risk changes in the geological disaster in the area covered by the project.The Sichuan-Tibet network project is an important construction project in China's western development strategy and is also China's first power grid project in Tibet.This paper takes the Sichuan-Tibet network project as the research object,investigates and analyzes the geological disasters and its influencing factors in the region along the route based on remote sensing and GIS technology,and summarizes the disaster geological model,disaster natural environment model,and disaster inducing model,and eventually selects ten evaluation factors to achieve the geological disaster risk assessment research along the Sichuan-Tibet network projects,the geological environmental factors include: elevation,slope,aspect,formation lithology and faults;natural environmental factors include: vegetation,rainfall and surface water systems;inducing conditions include: regional activity and seismic intensity.On the basis of combing and summarizing the results of regional geological hazard risk assessment,the GIS-based weights of Evidence method is selected to conduct a quantitative assessment of the risk of the geological hazards in the region along the project,and the posterior probability representing the risk degree of geological disaster in the study area is divided into four levels(high risk area,less high risk area,moderate risk area,and low risk area)by the natural breakpoint method.According to the success rate curve,the accuracy of the evaluation results is tested,and the result shows that the accuracy of this risk assessment is 90%,which indicates that the geological hazard risk assessment of the construction engineering based on weights of evidence in this paper has a good accuracy and applicability.It has been proved by the practice that the risk assessment of geological hazards based on the weights of evidence in this paper is a set of reproducible and quantitative models,which has a high accuracy and also has a strong operability and availability,the research results of this paper has important guidance and reference significance to the risk monitoring of geological hazards on infrastructure construction projects.