Ductility and energy absorbing behaviour of coal wash–rubber crumb mixtures

The reuse of waste materials, such as coal wash (CW) and rubber crumbs (RC), is becoming increasingly popular in large-scale civil engineering applications, which is environmentally friendly and economically attractive. In this study, the ductility and strain energy density of CW-RC mixtures with different RC contents compacted to the same initial void ratio and subjected to triaxial shearing are evaluated. As expected, the ductility and energy absorbing capacity of the waste mixture are improved with RC addition. This makes the use of CW-RC mixtures in substructure applications a promising development for future rail design where loads are expected to increase. Furthermore, empirical models for the shear strength and strain energy density based on the RC content are proposed. These models may be used as a guide to approximate the sheacr strength and strain energy density of these compacted CW-RC mixtures prior to the undertaking of extensive triaxial tests