Rheological properties of plastic-modified asphalt binders using diverse plastic wastes for enhanced pavement performance in the UAE

Abstract

The integration of waste plastics in asphalt mixtures has recently gained more popularity as a potential solution for repurposing waste plastics, while relieving the accumulation of plastics in landfills. This paper investigates the addition of plastic wastes from four waste products namely HDPE, PET, ABS, and LDPE, to asphalt binder at two contents of 2 % and 4 % by the weight of asphalt binder. The control and plastic-modified asphalt binders were tested for physical and rheological properties. Most of the used waste plastics increased the rutting parameter of the asphalt binder. The 4 % ABS plastic-modified asphalt binder managed to achieve the maximum Performance Grade (PG) of 82 while the 4 % PET achieved PG 76. Higher plastic content yielded higher resistance to permanent deformation. Asphalt binders modified with 2 % LDPE and 2 % HDPE yielded the best performance against low temperatures. The Linear Amplitude Sweep (LAS) test results at intermediate temperature showed that the best fatigue performance was attained using 4 % ABS at a strain level of 2.5 %, whereas at 5.0 % strain level, the 2 % PET achieved the maximum fatigue improvement (25 %) over the control. Simulated pavement performance using the AASHTOWare Pavement ME Design software showed noticeable extensions in pavement life for the plastic-modified asphalt binders against permeant deformation and fatigue cracking. The Life Cycle Cost Analysis (LCCA) displayed a reduction in the estimated LCCA cost for the plastic-modified asphalt binders by up to 50 % over the control.