Evaluation of the rheological and performance behaviour of bitumen modified with compounds including crumb rubber from waste tires

Abstract

The recycling of waste tires is one of the greatest concern the researcher have been addressing worldwide. In the field of road materials, several solutions have been studied but all of them present some issues, great or small. In the present study, the possibility to recycle the crumb rubber from waste tires in the production of compounds for bitumen modification was evaluated. In particular, physical, rheological and fatigue tests were carried out on three different compound-modified bitumens and on a reference SBS-modified bitumen. In particular, penetration, softening point, elastic recovery, performance grade, complex modulus, rheological parameters and fatigue resistance were measured in the laboratory at different ageing levels. The results showed that the bitumen including 6% by weight of the compound made of waste rubber and radial SBS had analogous or better performance compared to the reference bitumen including 4.8% of radial SBS in terms of physical properties, low-temperature behaviour, stiffness, elasticity, ageing sensitivity and fatigue resistance. The findings are very promising and encourage future investigations at mix scale.