Dynamic properties of dry sand/rubber (SRM) and gravel/rubber (GRM) mixtures in a wide range of shearing strain amplitudes

Recycled tire rubber in mixtures with granular soils has been found recently applications in many civil engineering projects. The paper presents a synthesis of the dynamic strain-dependent properties of the commonly used soil/rubber mixtures, which are necessary in any seismic design. We focus herein on high-amplitude resonant column tests on granular soil/rubber mixtures with varying percentage of rubber. The most important characteristics of the dynamic properties of the mixtures like the confining pressure, the content of rubber, the grain-size characteristics of the physical portion of the mixtures as well as the relative size of soil versus rubber solids, are thoroughly discussed. We propose generic normalized shear modulus and damping ratio versus shearing strain amplitude curves for dry mixtures of sand/rubber (SRM) and gravel/rubber (GRM) appropriate for the engineering practice. Finally, we summarize analytical expressions for small-strain shear modulus and damping ratio for SRM and GRM proposed in previous studies.

► In this study we examined the dynamic properties of granular soil/rubber mixtures.
► All experiments were performed in a fixed-free resonant column apparatus.
► We used simple analytical models to analyze the dynamic response of the specimens.
► We proposed generic normalized shear modulus and damping ratio versus shearing strain curves.