Feasibility of usage of waste plastic as a bitumen modifier: a review

Abstract

Bitumen is prone to deformations and cracking under severe temperatures and under fatigue. To overcome these drawbacks bitumen ismodified by adding various additives. SBS and crumb rubber are some of the conventional bitumenmodificationmaterials. Recently, waste plastic has also been identified as a viablematerial to be used in bitumen modification. This would decrease the cost of bitumen modification aswell aswould provide a sustainable solution forwaste plastic disposal. It has been found that incorporation ofwaste plastic in bitumenmodification could increase the fracture resistance, rutting resistance and thermal stability of asphalt pavements. However, the ductility, elasticity and creep resistance were found to be decreased in waste plastic modified bitumen. Further, increased viscosity due to incorporation of waste plastic in bitumenmodification had induced poor workability as well as higher mixing and paving temperatures. Increased temperatures not only cause ageing of bitumen but also cause emissions which could affect adversely on the environment. This paper critically reviews the properties of waste plastic modified bitumen with respect to several factors: types of plastic, modification methods, optimum plastic percentage, mixing temperature etc. Further, the paper discusses about the remedial measures that are being explored to improve the aforementioned drawbacks of waste plastic modified bitumen.