Preparation and Pavement Performance of Highly Viscoelastic Antifatigue Asphalt

Abstract

Asphalt is the key factor in ensuring the service life of asphalt pavement, but the commonly used asphalt has difficulty meeting the requirements of long service life. To increase the durability of road materials and extend the service life of asphalt pavement, this paper used base asphalt, styrene–butadiene–styrene (SBS), activated desulfurized rubber, and aromatic oil to prepare highly viscoelastic antifatigue asphalt. The results demonstrate that the optimal dosages of SBS and activated desulfurized rubber are 3.5%–4.5% and 22%–25%, respectively. The 60°C dynamic viscosity of SBS–rubber composite–modified asphalt reached 516,700 Pa·s, which was 1.3 times that of SBS-modified asphalt. The cohesion, viscoelasticity, and high-temperature and low-temperature performance of the modified asphalt was found to be superior. The high-temperature grade of the original asphalt can withstand temperatures up to 100°C, whereas the low-temperature grade can withstand temperatures as low as −24°C. The 10% strain level of highly viscoelastic antifatigue asphalt has an Nf value of 8,412, which is 3.3 times that of the SBS-modified asphalt, demonstrating the outstanding fatigue performance of the asphalt. Furthermore, the pavement performance of the highly viscoelastic antifatigue asphalt mixture was examined. The dynamic stability of the mixture was found to be enhanced by 1.9 and 2 times, respectively, compared with the rutting performance of SBS-modified asphalt and rubberized asphalt mixtures. The pavement performance of highly viscoelastic antifatigue asphalt mixtures was improved significantly, which is a prominent advantage for durable pavements. Consequentially, the results of this research promote an innovative approach to the development of a durable asphalt for permanent pavement, ultimately improving the sustainability and durability of asphalt pavement.