The effect of adding rubber crumbs on the cyclic permanent deformation of waste mixtures containing coal wash and steel furnace slag

Among the numerous studies into the dynamic loading behaviour of rubber crumbs–soil/waste mixtures, the main focus is on how the content of rubber crumbs (⁠$Rb%$⁠) affects the damping ratio, shear modulus and total deformation. However, research into the influence of $Rb%$ on the permanent strain rate (⁠$ε˙p$⁠) and the deformation mechanism under repeated loading is very limited. In the current study, the cyclic deformation response for waste mixtures of steel furnace slag (SFS), coal wash (CW) and rubber crumbs (RC) is analysed and the test results reveal that $Rb%$ has a significant influence on the initial $ε˙p$ and the slope of the permanent axial strain rate line, whereas cyclic deviator stress (⁠$qcyc,max$⁠) mainly affects the initial $ε˙p$⁠. The influence of $Rb%$ and $qcyc,max$ on  the $ε˙p$ value of the waste mixture is incorporated in an empirical model, which enables prediction of the permanent deformation mechanism of SFS + CW + RC mixtures with wider-ranging amounts of RC and higher cyclic deviator stresses.