Experimental study of Colombian volcanic ash soil classification in the Colombian southwest with SUCS, AASHTO method and a new classification method

Abstract

It is presented the results of a comparative study of three classification systems for fine soils: The Unified System of Soil Classification (USCS), American Association of State Highway Officials (AASHTO) and a new soil classification based on electrical sensitivity [1]. The new classification uses parameters such as chemical sensitivity and properties in soil pore fluids that have not been taken into account by the classification methods currently used in geotechnics. These three methods are applied to samples of soils derived from volcanic ash that are of particular interest in the Andean region of Colombia to be a common occurrence groundfloor in one of the location most densely populated in the country. As an important conclusion of the study, it was obtained that a soil classification based on the electrical sensitivity of the particles better describes the plastic behavior of soils derived from volcanic ash, ultimately enhancing the selected engineering solution.