Evaluation of slope disaster susceptibility based on GIS and three-level fuzzy evaluation method

In the past, the fuzzy evaluation model of slope stability is mainly two-level model, and the classification level is relatively single, which cannot map the influencing factors of slope disaster comprehensively and objectively. In order to improve the accuracy of evaluation results, a three-level fuzzy hierarchy evaluation model for slope hazard is proposed. A total of 22 factors affecting slope stability in 4 categories and 9 sub-categories were selected to constitute the basic evaluation system. Taking the highway slope of the multi-line connecting line as an example, the weight was determined by AHP method, and the weight was adjusted by the back analysis of the typical highway slope. Finally, the stability of other highway slopes in the study area is evaluated on the spot, and use the information concentration formula to check, then the susceptibility level prediction of slope disasters in the whole section is realized based on GIS platform. The analysis results show that among the 77 highway slopes studied, unstable slopes account for 7.8% of the total slopes, less stable slopes account for 22.1%, quasi steady slopes account for 42.8% and steady slopes account for 27.3%. Therefore, the disaster prone zoning of highway slopes along the connecting line of Chengdu Mianyang double track line is obtained. In fuzzy comprehensive evaluation, information set formula can be used to modify the evaluation results to a more extent. In this study,compared with the second-level model, the accuracy of the three-level model improved by about 16.7%.