Problemática y conocimiento actual de Las tefras tierra blanca joven en el área Metropolitana de San Salvador, El Salvador

currently the metropolitan area of san salvador (amss) is experimenting serious problems of mass movements, erosion, collapse or settlements, phenomena that in el salvador are popularly encompassed by the term “carcavas”. this problematic is presented mainly in the volcanic tephras tierra blanca joven (tbj), product of the last plinian eruption of ilopango caldera, whose products are an intercalation of pyroclastic fall, flows and surge. the tephras are unsaturated and the geotechnical information shows a decrease of shear strength and collapse when saturated. to characterize properly this material is important to know the relationship of moisture content with the volume changes and apparent cohesion, which are related to suction and cementation. the understanding of the behavior of the geological materials can help in running slope stability simulations and geotechnical design in general.