Study on Performance Optimization and Maintenance Technology of Regenerant on Modified Asphalt Pavement

Abstract

With the extensive network of high-grade highways in China entering a maintenance phase, the disposal of large quantities of Reclaimed Asphalt Pavement (RAP), particularly containing aged SBS-modified asphalt, has become a pressing issue. Addressing the performance degradation of aged SBS-modified asphalt, this study investigates the effectiveness of a composite rejuvenator in restoring and optimizing its properties. Through laboratory tests, including penetration, softening point, ductility, and Dynamic Shear Rheometer (DSR) tests on asphalt with varying rejuvenator content, the high-temperature, low-temperature, and fatigue performance of the rejuvenated asphalt were systematically evaluated. The results indicate that this composite rejuvenator effectively replenishes the light fractions of the aged asphalt and restores its rheological properties, with an optimal dosage identified at 6%. At this dosage, the high-temperature performance of the rejuvenated asphalt recovers to over 95% of that of virgin asphalt, while its low-temperature performance is significantly enhanced, and its fatigue life is increased by approximately 30%. This research provides important theoretical and data support for maintenance techniques applied to modified asphalt pavements incorporating RAP.