Dynamic properties of sand-tyre chip mixtures

The stockpiling of scrap tyres is a significant environmental hazard and has attracted ample research attention to explore viable solutions to recycling and reuse of scrap tyres. The authors have recently proposed a novel seismic isolation method using sand-tyre chips (STCh) mixture for protecting buildings and infrastructure. Although the static properties of STCh mixture have been extensively studied, the investigation on the dynamic properties of the mixture has been limited. The dynamic properties of STCh mixture are important to its application for seismic protection of infrastructure. This paper presents the dynamic properties (shear modulus and damping ratio) of STCh mixture for medium to large range of shear strain levels (0.15% to 0.5%). The effects of the level of cyclic shear strain, number of cycles and effective initial confining pressure have been investigated. The dynamic properties of STCh mixture presented in this paper will also be essential for the application of the mixtures in other civil engineering projects.