An experimental analysis of crumb rubber modified asphalts subjected to moisture conditioning

This study presents the results of an experimental investigation into the durability and mechanical behaviour of crumb rubber-modified asphalt (CRMA) mixtures under moisture-induced degradation. To advance sustainable pavement engineering, three distinct CRMA formulations were subjected to controlled moisture conditioning and freeze–thaw cycles, thereby simulating environmental exposure typically encountered during service. Key performance indicators such as indirect tensile strength (ITS), unconfined compressive strength (UCS) and tensile strength ratio (TSR), were measured to assess the materials’ resistance to water-induced deterioration. Load–displacement data from ITS tests were further analysed to extract fracture-related parameters, including post-peak stiffness and energy absorption capacity, offering insights into the cracking behaviour of the modified mixes. Results indicated a marked decline in mechanical performance with increasing moisture exposure, with significant reductions in both tensile strength and fracture resistance. Comparative analysis with conventional asphalt mixtures from the literature was conducted to evaluate how the selected parameters can predict cracking resistance.