Caractérisation et estimation du gonflement des argiles algériennes, cas des argiles de Médéa

Abstract

The clayey material hard and brittle when dry, presents the particularity of changing its consistence as a function of its water content. A certain percentage of moisture may transformed it into a plastic and manageable material. Depending on the particular structure of clay minerals, these modifications of consistence may be accompanied by more or less substantial volume variations, manifested, either, as a sharp increase of volume (swelling phenomenon) when the water content increases or shrinkage (shrinkage phenomenon) in period of marked rainfall. This behavior is essentially linked to some of environmental parameters of these soils, for example: the geology and lithology of the site, the climate, etc. The prediction of swelling potential of soil is possible with empirical methods that based on identification parameters, such as plasticity and particle size, determined during the reconnaissance campaigns. Once the character of the swelling sensed in preliminary recognition phase, an estimate of the amplitude and the pressure of swelling can be established by correlations that tend to link the swelling parameters with geotechnical parameters obtained from identification tests. It is in this aspect that is inscribed this article which treating the case of an Algerian Site. The results show a concordance between the deferent empirical methods applied. These results are compared with those obtained for the oedometric swelling tests. The evolution of the clay structure during shrinkage and swelling is followed with the aim of understanding the mechanism of swelling. © Owned by the authors, published by EDP Sciences, 2014.