Rheology, Chemical Composition, and Microstructure of the Asphalt Binder in Fine Aggregate Matrix after Different Long-Term Laboratory Aging Procedures

Abstract

This study investigated the common aging protocols for binders and asphalt mixtures on fine aggregate matrix (FAM). Currently, no unified aging protocols are specified for laboratory-prepared FAM. The majority of FAM-related aging research used asphalt binders and mixture aging specifications. However, the practicality of employing these methods on FAM was not extensively examined. The rheological properties, chemical composition, and microstructure of aged binders extracted from FAM were extensively evaluated. For comparison, pressure aging vessel (PAV) aged binders and aged binders extracted from asphalt mixtures were similarly tested. Statistical analysis was performed on aging indices derived from test findings. Matching the aging level of FAM, aged binders, and asphalt mixtures required shortening the aging time for FAM under PAV aging or prolonging the aging time of loose mixes aging at 95°C during the early stages of aging. FAM’s aging level was not statistically different from that of binders and mixtures under severe aging circumstances. The findings of this paper will be valuable in multiscale testing of asphaltic materials.