MODIFICATION OF HOT MIX ASPHALT USING POLYETHYLENE THEREPHTHALATE (PET) WASTE BOTTLES

Abstract

This study covers usage of Polyethylene Therephthalate (PET) waste bottles to modify the properties of hot mix asphalt (HMA) mixtures. The study adopted usage of ground PET waste bottles with maximum particle size of 2.36 mm with different contents (0.1%, 0.3%, 0.5%, 0.7%, 0.9%, and 1.1% by the weight) to replace an equivalent portion of fine aggregate. The study involved a number of laboratory tests to investigate the effects of the mentioned PET content on the engineering properties of HMA. In addition to tests implemented to specify the properties of materials used and to determine mixing and compaction temperatures, the testing program included Marshall tests, rutting susceptibility tests, and indirect tensile strength tests applied on a number of control (unmodified) and modified samples. The results exhibited significant improvement in engineering properties of mixtures modified with optimum PET content (which was found to be 0.5%) in terms of increase in stability, stiffness, and indirect tensile strength and decrease in rutting susceptibility without adverse effects on the other desirable properties of the mixture.