Cartographie de l’exposition aux risques naturels et rectification du tracé d’un tronçon de l’Autoroute Est-Ouest, cas d’un tronçon du lot Constantine-Annaba.

Abstract

Based on Raster calculation, statistical processing and GIS modeling; our study proposes a landslide susceptibility and risk zonation along the A1 highway in Zighoude Youcef and Didouche Mourad municipalities , Constantine province. The inventory of landslides is made by field work. Factors influencing the landslides occurrence include slope angle, slope aspect, elevations, lithology, faults, and precipitation. Different classes of thematic layers have been proposed for these factors. Weights were assigned, resulting in weighted maps of each factor in the information system. A hierarchy of degrees of susceptibility and risk was estimated and mapped by superimposing causative factor maps by applying an expert approach. The results of the analysis were validated with a comparison between the landslide localization map and the probabilistic model. The resulting maps can be used for the mitigation of such phenomena and for the organization of land use plans.