China Plastics ›› 2025, Vol. 39 ›› Issue (9): 108-114.DOI: 10.19491/j.issn.1001-9278.2025.09.017

• Plastic and Environment • Previous Articles    

Effect of modified waste PET pellets on performance of asphalt and its mixture

YANG Fan1,2, HU Yihong3, YANG Fayong4, HU Bin5, JING Hongjun1,2, LI Haibin1,2()   

  1. 1.School of Architecture and Civil Engineering,Xi’an University of Science and Technology,Xi’an 710054,China
    2.Road Engineering Research Center,Xi’an University of Science and Technology,Xi’an 710054,China
    3.Hunan Highway Maintenance Engineering Co,Ltd,Changsha 410000,China
    4.Xi’an Highway Research Institute Co,Ltd,Xi’an 710065,China
    5.Shangluo Highway Bureau,Shangluo 726000,China
  • Received:2024-09-29 Online:2025-09-26 Published:2025-09-22

Abstract:

This study investigated the application of modified waste polyethylene terephthalate (PET) pellets as an asphalt modifier for road construction. PET⁃modified asphalt was prepared with varying modifier contents (4.5 %~6.5 % by mass of base asphalt) and systematically evaluated. Comprehensive testing identified 6.0 % PET content as the optimal modifier content, demonstrating significant performance improvements: a 33.3 % reduction in penetration degree, 21.1 % increase in softening point, and decreased ductility compared to base asphalt. Subsequent mixture evaluation through rutting tests, low⁃temperature bending tests, water immersion Marshall tests, and freeze⁃thaw splitting tests revealed enhanced performance characteristics. The modified mixture exhibited 151.1 % greater dynamic stability, along with 5.6 % and 3.0 % improvements in residual stability ratio and freeze⁃thaw splitting strength ratio, respectively. While low⁃temperature crack resistance decreased marginally (5.3 % reduction in flexural tensile strength and 6.7 % in strain), the results indicated that PET modification substantially improved high⁃temperature stability and water resistance of asphalt mixtures. This study validates the technical feasibility of using waste PET in road engineering while providing an effective recycling solution for plastic waste, contributing to sustainable infrastructure development.

Key words: polyethylene terephthalate, modified asphalt, asphalt mixture, high temperature stability, low temperature crack resistance, water stability

CLC Number: