Investigating the Properties of Asphalt Concrete Containing Waste PET and Rubber Asphalt

In this research the effects of waste polymer of PET on the performance of asphaltic mixtures containing rubber asphalt are investigated. To this end, two different sizes of waste PET particles were added into an asphalt concrete at different percentages of 2, 4, 6, 8 and 10% (by the weight of asphalt binder). After determination of the optimum binder content of each mixture, they were subjected to different tests of Marshall Stability, indirect tensile strength and dynamic creep tests. Dynamic creep tests were conducted using UTM-10 under 300kPa and temperature of 40°C for evaluating the permanent deformation behavior of the mixtures containing different percentages of PET. The results showed that the addition of PET into the asphaltic mixtures containing rubber asphalt resulted in the improvement of Marshall Stability and Marshall Quotient compared with the control mixture without PET, with the highest stability was obtained for the mixtures containing 10% of PET. The indirect tensile strength tests results showed that, for both sizes, the highest indirect tensile strength was obtained by the addition of 2% of PET, beyond which the indirect tensile strength decreased with increasing PET content. The dynamic creep test results showed that the mixtures containing PET have a different behavior under dynamic loading compared with that under static loading. It was found that the addition of PET results in the reduction of resistance against permanent deformation under dynamic loading, such that, the resistance decreased with increasing PET content. The Marshall stability, indirect tensile and dynamic creep tests results showed that the mixtures containing finer PET particles have a higher resistance than those containing coarser particles.