Dynamic behavior of sand-rubber mixtures based on hollow cylinder tests

Abstract Different additives can be utilized to improve the mechanical behavior of soils including their dynamic properties. Among these additives, crumb rubber, as a recycled material, can provide economic and environmental advantages in addition to the improved mechanical behavior. In this paper, different aspects of dynamic behavior of sand-rubber mixtures were investigated over a wide range of shear strains implementing dynamic hollow cylinder tests. For this purpose, the effects of various parameters including relative density, rubber content, confining stress, and size of rubber particles were studied in detail. The results demonstrated that dynamic properties of sand-crumb rubber mixtures were mainly influenced by rubber content and confining stress values, while relative density and rubber particle size were less effective in this regard. Moreover, it was found that dynamic behavior of the mixtures was completely strain-dependent such that at strain ranges lower than a threshold value, which depended on the applied confining stress, an increase in rubber content led to higher damping ratios, while at strain levels higher than the threshold value a reverse trend was observed.