Innovative Integration of Recycled Plastics for Flexible Pavement Design

Plastic waste is a major problem due to its non-biodegradable nature. Incorporating recycled plastic in road construction enhances mechanical properties effectively. This paper encompasses methods to solve two major issues in Nepal, largely focused in major cities of Nepal: primarily, the management of solid waste, specifically with consideration of used plastics which have engulfed main cities; secondarily, the development of potholes on roads due to heavy traffic weight and some environmental factors such as excessive precipitation and infiltration, flooding conditions. This study inspects the effect of combining waste thermoplastic polymers like High-density polyethylene (HDPE), Polyethylene Terephthalate (PET), and Polypropylene (PP) in flexible pavement design, at various plastic compositions. The plastics were grinded and mixed with the bitumen at a temperature range of 160 °C–170 °C. Various tests such as the Marshall Stability test, Penetration test, Ductility test, and, Softening Point test were carried out to find the resulting modifications from base bitumen. It was observed that the plastic mixed sample upto 10% by weight shows sufficient mechanical properties of pavements. Being a cheap and effective way of improving the capacity of flexible pavement, It is one of the alternative ways to use plastic waste.