High and low temperature performance of polyethylene waste plastic modified low noise asphalt mixtures

Abstract

• Waste plastics can be a viable alternative for reducing polymer in asphalt mixtures. • PE compared to non-PE with same binder improved resistance against deformation. • PmB mixture compared to PE showed higher resistance against cyclic loading. • SCB test showed PE mixtures had slightly improved fracture energy toughness. Waste plastic in low noise asphalt mixtures can be a viable alternative to asphalt mixtures with polymer modified bitumen. The performance of low noise semi dense asphalt (SDA) mixtures with waste polyethylene (PE) plastic is investigated. The cyclic compression test (CCT) and semi-circular bending (SCB) test was used for characterization of high and low temperature performance. The CCT results revealed that the PmB mixture had shown significantly higher resistance compared to the PE mixture. However, the PE modification showed some improvements in terms of CCT loading when compared with mixtures using the same base binder without PE. The SCB test results found that on average using higher content of PE mixtures had slightly improved fracture energy and lower fracture toughness compared to asphalt mixtures using polymer modified binder (PmB). The electron microscopy images showed that the PE does not completely melt during the mixing process and exists as elastic bodies within the mixture. The findings showed that at low temperatures, both PE and binder behave elastically, whereas at higher temperatures, PE remains elastic, and binder's viscoelasticity becomes dominant. These results highlight the importance of selecting proper base binder for such modifications with waste plastic.