The construction of factors for assessing the risk of collapse at loess slopes in northern Shaanxi Province

The selection and quantification of factors are very important in landslide susceptibility, hazards and risk assessments. At present, GIS tools are widely used in the world to extract the information of topography, lithology, distance from river or fault, land use, vegetation, precipitation, density of river, etc. These factors have been applied to assessing the landslide susceptibility or hazards with great achievements, but they still have some limitations. Firstly, they can not supply a set of relevant factors for a specific type of landslide. Secondly, some of the factors, such as precipitation and lithology, show generality at a region scale,. Thirdly, the integrated risk assessment factors have not been set up yet. This paper studied a specific type of landslide called "loess collapse" which is widely developed in northern Shannxi Province, utilized the international popular landslide risk management theory to build up a general framework of assessing factors. On the basis of data statistics from field investigation, the authors analyzed the sources of hazards and influencing factors of damages. Totally 36 factors in 16 catalogs were set up in four aspects, i.e., slope failure, collapse intensity, elements in risk, and vulnerability. The construction of these factors will provide a basis for further assessment of loess collapse risks.