| description abstract | Given the characteristics of anti-cracking layer asphalt material and the shortage of existing research on the subject, thermoplastic styrene-butadiene rubber (SBS), crumb rubber modifier (CRM), and plasticizer (DBP) were used as modifiers to develop a composite modified asphalt suitable for the anti-cracking layer. A reasonable modifier dosage was determined through ductility, penetration, softening point, and elastic recovery tests. Pavement performance of the composite modified asphalt was evaluated through dynamic shear rheological test, viscosity and mechanical performance temperature scanning, as well as fatigue and low-temperature bending beam tests to determine the best dosage of rubber powder. Test results showed that the optimum SBS, DBP, and CRM dosages were 5%, 4%, and 4%, respectively. The new composite modified asphalt exhibited good pavement performance and could satisfy the requirements for the anti-cracking layer. The results of this study could provide an important reference for a rational choice in asphalt material for the anti-cracking layer, and consequently, extend the service life of pavement structures. | |