Effect of Gradation on the Dynamic Response of Sands

Abstract

This paper presents the dynamic soil parameters of sand viz., shear modulus, and damping ratio, which are needed to be considered for the structural design in the areas susceptible to cyclic loading. The aim of the research is to relate the gradation of sands with dynamic properties at small strains. These properties, in fact, are the function of soil characteristics, loading conditions and the mean effective principal stress at any instant. It was witnessed from the stiffness degradation and damping characteristics of sand that the gradation significantly influences the stiffness due to alteration in the stress state of the soil. Furthermore, the data also revealed that the threshold shear strain at the onset of modulus degradation slightly reduces with increase in coefficient of uniformity.