Geotechnical risks map "Case of the ZHUN EAST, Saïda city - ALGERIA"

The urban expansion and the increase in population led the urbanization to use the spaces "called at risks". The integration and the treatment of ground's movements constitute an important characteristic of the equilibrium established by nature. In the Saida town (Algeria), many projects built on grounds with problems showed signs of degradations such as cracks in structures. These degradations led to the total destruction of the building. The principal causes of these disasters are: the nature of the expansive nature of soils and landslides, disaster phenomenon not considered in the first study of these constructions. The damage also touched road embankments, highways and foundations. In order to solve these problems, it was necessary to propose a geotechnical and risks map for the ZHUN EAST (ESSALAM city, Saida), city which includes several yard of the soil with problems, using the geographical information systems (GIS/MapInfo). These tools enable us to express the perception of space and data processing, and consequently the cartography is carried out in an optimal way. These geotechnical and risks maps have a great part of importance in all levels of a study as information, working paper, alert, and especially is a tool for the decision-making aid, by expressing tendencies and orientations. They enabled us to give a field representing the active and potential movements with a hierarchy of risks to guide the developer and the engineer.