Modeling and risk assessment of landslides using fuzzy logic. Application on the slopes of the Algerian Tell (Algeria)

Natural risk regains the notion of exposure to natural disaster or dangers of any natural hazard. Its management consists in the assessment and the anticipation of risks, as well as to the setting up of an alert system. From natural risk, we mentioned one bound to landslides in natural slopes that are difficult to surround and approach. Nevertheless, the assessment of landslides risk is the object of several works of research and many models, based on the multicriteria analysis, have been established. It should be noted that based on multicriteria approach, we evaluated, in a previous work, the landslide risk using the weighted sum model. The results reveal that the use of qualitative parameters influenced the classification of slope. This led us to adopt fuzzy logic approaches for assessment. This work examines the contribution of fuzzy sets theory to modeling and assessment of landslides risk in natural slopes. It brought to use this approach that permits the survey of these imprecision in adopting a Mamdani model. The method has been applied on slopes, situated in four areas of the Algerian Tell, where each is characterized by the different natural conditions. The result, put in evidence, summarizes modeling and risk assessment of landslides in an optimal classification of slopes according to the degree of instability risk. It allows decision makers to put in strategies for possible work of these slopes.