Adhesion Properties Between Crumb Rubber Modified Bitumen and Aggregate

Moisture-induced durability distresses are the key barriers of rubberised asphalt that impedes its further application. It is of vital importance to improve the adhesion properties between rubberised binders and aggregates. This study aims to investigate the adhesion property of CRMB and examine the effects of adhesion promoters on the bonding properties at the CRMB–aggregate interface. Both DSR-based direct-tension tests and rolling bottle tests were conducted on the selected combinations of bitumen and aggregate. Results indicate an increase in adhesive strength and bond energy of CRMB associated with ageing process. The addition of amine-based adhesion promoter makes CRMB stiffer and more elastic, also increases the adhesive strength and bond energy. Comparing to the bitumen modification method, aggregate coating with adhesion promoters is more effective in improving the bitumen–aggregate adhesion performance.