Modelación y caracterización física 3D, mediante prospección geofísica del deslizamiento de Trigales Altos, Cuenca-Ecuador

Abstract

In Azuay-Ecuador, the Trigales Altos citadel has been listed as an area susceptible to hillside instability phenomena. Recent studies (Gestión de Riegos, 2015; Tecnosuelos, 2006) have identified an active landslide in the area that affects a landfill without drainage, located on expansive soils, damaging homes, roads, drinking water networks and sewerage. The present work proposed to analyze the stability of the slope by means of the physical and geotechnical characterization of the subsoil strata of the landslide. The joint evaluation with the methods of electrical resistance, refraction seismic and multichannel surface wave analysis (MASW) is proposed, in order to obtain more complete and greater information on the automation of the physical and geotechnical conditions of the terrain. The results indicate that the type of soil existing in the area is type D according to the NEC 2015 classification, presenting Vs30 values between 266 and 313 m/s, which explains its poor geotechnical properties. It was identified that the fault plane is between 9 and 12 meters deep, due to a lithological change between fine clay soil belonging to the Santa Rosa geological formation and sandy-silty soil with centimetric clasts typical of the fluvial-glacier terrace that emerges in the area. It was found that the subsoil strata are distributed vertically which causes deformation, giving rise to strips of geotechnical weakness. In conclusion, the area's soil lacks carrying capacities for the support of anthropic constructions.