Dynamic deformation characteristics of EPS particles lightweight soil based on Davidenkov model

Abstract

The dynamic deformation characteristics of lightweight soil is studied using consolidated undrained dynamic triaxial tests to predict its nonlinear stress and strain behavior under traffic load. The results showed that the influence of confining pressure on attenuation of the dynamic shear modulus ratio became significant with increasing EPS (expanded polystyrene) particle content or the cement content. The attenuation curve of the dynamic shear modulus ratio was evaluated using Davidenkov model parameters, A, B and γ 0. It was proved that parameter A was mostly affected by EPS particle content and confining pressure with its value ranging between 1.1 and 1.85. The parameter γ 0 was affected by cement content and confining pressure, and its value ranged between 0.0007 and 0.0016. The parameter B was found to range between 0.38 and 0.55, in general. The relationship curves between damping ratio and dynamic shear strain revealed two forms, S-shaped and bell-shaped. The verification tests showed that Davidenkov model could predict accurately the dynamic deformation characteristics of lightweight soil both under changing stress state and under constant gradient loading conditions. These results provide a theoretical basis for determining deformation of a lightweight soil subgrade under traffic load.