GIS-based Geological Hazard Susceptibility Assessment Along Guizhou Section Of Sichuan-Guizhou Railway

There have been a large number of profile reports of hazards on national railway networks in western mountainous area of China over recent years.Sichuan-Guizhou railway is one of the most hazard-prone aging rail networks along which we make evaluation on these hazards through extensive field survey.Further,combined with documentary files,inventory hazard database was created.Based on GIS and statistic models,the data were applied in the hazard susceptibility zonation.The main research results are as follows:(1)This dissertation analyzes the geological conditions and the influencing factors of the hazards along the railway through both extensive field work and copious literature.Combined with the principle of analytic hierarchy process,this dissertation carries out assessment of the geological hazards along the survey.(2)Based on the GIS software,the geology hazard database of the study area was established according to the geological hazard investigation and the geological hazard record.Conditioning factors considered for the area were elevation,slope,aspect,lithology,river buffer,and tectonic buffer.Combined with GIS spatial analysis function,the conditioning factors were ultimately imported into GIS in quantitative processing.(3)According to the information value model,the information quantity of each class from each factor is obtained by calculation.Afterwards,we assign the information quantity of each factor into the coverage by GIS,and the final susceptibility map is obtained by using the grid calculator and reclassification function in GIS as well.(4)According to the principle of Logistic regression,non-geological hazard points had to be extracted in GIS for calculation.The geological hazard points and non-geological hazard sites were divided into training and validating group.According to the training group,the vulnerability data were deduced based on SPSS software and the regression equation was introduced into the GIS software to obtain the final hazard distribution map of the research area of the railway.The final results were tested by ROC curve based on the validating data.