Comparative study on multi-dimensional characteristics of crumb rubber-modified asphalt mixtures with varied content

Abstract To clarify the impact of increased crumb rubber content on asphalt mixture performance, five aggregate gradations and three modified asphalt binders were combined to formulate eight asphalt mixtures for multi-dimensional comparative testing. Key findings: 1) High-content rubberized asphalt mixtures exhibit superior road performance compared to SBS-modified asphalt counterparts; 2) 40% rubber-modified mixtures demonstrate better fatigue resistance across gradations than 30% blends, with performance advantage peaking then diminishing as strain levels increase; 3) Rubberized asphalt mixtures show significant fatigue life advantages over SBS-modified types; 4) The increasing nominal maximum aggregate size (NMAS) reduces fatigue resistance within the same rubber content group, with accelerated fatigue life degradation under elevated strain conditions.