Evaluation multi-échelle de la susceptibilié des terrains de la région de Béjaia aux mouvements de masse

Abstract

Our work consists in making a multi-scale assessment of the susceptibility of the lands of the Bejaia region to mass movements. The first step is to delineate the study area and describe the facies in the area. A hydroclimatological study was hen carried out using rainfall data from four surrounding stations between 2007 and 2016. A precipitation map is then obtained and finally the hydrological balance of the region is deduced, parameters necessary to link the effect of water To the instabilities of the land. After obtaining information layers, using a geographic information system (ArcGis), a multicriteria interpretation and a geospatial treatment are made to map the hazard studied. This map is based on the field data as well as those obtained from the laboratory. It is observed that the movements of land, mainly landslides, are more present in the South-East region of our zone. A work of instability calculation was then done using the simplified Bishop method and the Slide software, this allows to have the values of the safety coefficient according to the existence of a seismic sheet or a seismic solicitation.