Modification of Bituminous Mixture using Polyethylene Granules
Pavement performance is generally influenced by traffic, moisture, and quality of construction and maintenance. Deterioration on road surface can develop due to one or combination of these factors. In order to improve pavement performance, the modification of bituminous mixture for road surface can be achieved by adding additives or modifiers in the mix. This study presents the utilization of two types of polyethylene (PE): high density polyethylene (HDPE) and low density polyethylene (LDPE), a plastic waste products as an additive to enhance the properties of bituminous mixture. PE has been extensively used in industrial and domestic applications due to its low-cost, lightweight and durable properties. Wearing course samples of control and modified mixes were prepared using Marshall mix design method and according to Standard Specification for Road Works as guidelines. Three types of HDPE/LDPE blends with ratios of 75/25, 50/50 and 25/75 have been prepared and tested. It was found that polyethylene modified bituminous mixes show significant increment in Marshall stability and lower optimum bitumen content (OBC) in comparison to unmodified mix, where equal blend of HDPE/LDPE (50/50) shows a better Marshall properties. This shows that an addition of polyethylene in bituminous mix can withstand higher traffic loading with lower bitumen content.