Investigating the High- and Low-Temperature Performance of Warm Crumb Rubber–Modified Bituminous Binders Using Rheological Tests

Rubberized asphaltic materials have been frequently combined with warm-mix asphalt technologies to tackle the issues of high energy consumptions and emissions during construction. Effective accurate characterization binder properties is conducive improvement long-term pavement performance. The current study aims quantify effects rubber content additives on rutting thermal cracking performance crumb rubber–modified bitumen (CRMB), explore modification mechanisms their impacts CRMBs containing different contents after aging were subject multiple stress creep recovery (MSCR) tests low-temperature frequency sweep using a dynamic shear rheometer (DSR) 4-mm loading plate investigate high- performance, respectively. Rheological also conducted phases CRMB understand mechanism. Results show that binders superior resistance due modification. or more prominent at higher concentrations. are different. Generally, wax-based additive improves but negatively affects In contrast, chemical-based has an opposite effect except for high-temperature neat bitumen. stiffening phase contribution swollen particles in matrix together contribute peculiar viscoelastic response CRMB, i.e., stiffer/softer elastic high/low temperatures. This mechanism explains CRMB.