A general model for the small-strain stiffness of saturated residual soils: back analysis of a database and case study

A review analysis of a database of 237 small strain stiffness measurements performed on 35 different residual soils is presented. The reinterpretation of the tests was conducted with respect to the loading conditions and physicochemical parameters published in the literature. Besides, the database was completed with the results of a case study from a dam construction project in the French West Indies. On the basis of a detailed and carefully justified analysis, parameters influencing the response of saturated residual soils to small strains are identified, is proposed. The correlations between the identification characteristics of the residual soils (initial void ratio, Atterberg limits, clay fraction) and the model parameters are investigated. The article proposes a general model for the evaluation of the small-strain stiffness of saturated residual soils using, in addition to the mean effective stress (p') and the maximum mean effective stress (p'max) the initial void ratio (e0) and, for intact soils, the clay fraction (CF) or, for remoulded soils, the plasticity index (PI).