Modification of Bitumen Properties Using Waste Polymer in Context of Bangladesh

Proper disposal of plastics and its derivatives is one of the biggest challenges all over the globe. Due to the improper management of plastic product environment is being polluted. Plastic waste generation and plastic waste-based pollution in Bangladesh is leaping at a high pace. Among numerous ways of disposal of waste plastics, one can be using it in flexible pavement construction. According to the Bangladesh Waste Database 2014, Dhaka city alone produces 25.44% (5,925.51 tons/ day) of waste, of which 8.45% is plastic. In the construction of bituminous pavement, plastics, as well as construction debris, are being used in the form of aggregate and filler materials popularly. This study focusses on the improvement of properties of bitumen by blending it with LDPE (Low-density polyethylene) and PP (Polypropylene) at a different proportion. Three cases were considered in the study for plastic waste addition, Case-01:- only LDPE; Case-02:- LDPE: PP=3:1; Case-03:- LDPE: PP=1:1. For each case, 3%, 6%, 9%, 12%, and 15% of plastic waste was mixed with bitumen. It was found that the penetration value and ductility decrease with the increasing proportion of plastic waste in bitumen, whereas the softening point increases for every case. Loss on heating, flash & fire point also been improved with the plastic addition. The performance of Case- 03 (LDPE: PP=1:1) is better than others. Minimum penetration value, 11 and maximum softening point, 90°C, is found for this case, which indicates a 90% improvement compared to virgin bitumen. Due to the addition of plastic waste, the ductility always gets affected. But overall, a significant improvement in the properties of bitumen is noticeable.