Effect of ultra-high-molecular-weight polyethylene on the performance characteristics of hot mix asphalt

Abstract

In order to improve the performance of asphalt binder and asphalt mixture against the destructive effect of traffic and weather conditions, there are different methods, the use of additives is one of the most common of these methods. In this study, the effect of ultra-high-molecular-weight-polyethylene on the rheological properties of the asphalt binder at different temperatures and functional characteristics of asphalt mixtures was investigated. In order to prepare the samples, 2 and 4% of ultra-high-molecular-weight-polyethylene (by weight of the asphalt binder) was added to PG 64-16, and its effect was examined on the rheological properties of asphalt binder, including the dynamic shear rheometer test at high and middle temperatures in unaged, short-term and long term aged conditions. Also, the repeated load axial test, indirect tensile fatigue test and tensile strength ratio in 1, 3, and 5 cycles were conducted to investigate the rutting potential, fatigue cracking, and water sensitivity of asphalt mixture, respectively. Based on the results obtained from the complex modulus (G*) and phase angle (δ) values at high and middle temperatures, the rutting (G*/sin δ) and the fatigue (G*.sin δ) parameters in asphalt binder samples made with 4% of the ultra-high-molecular-weight-polyethylene showed the best performance against permanent deformation and fatigue cracking, respectively. Also, the results of asphalt mixture functional tests indicated the use of UHMWPE, with better adhesion between asphalt binder and aggregates, increased fatigue life, reduced the permanent deformation and improved the moisture sensitivity of the modified samples in comparison to control samples. An overview of the results obtained in this study can be said that the use of 4% polymer additive has the best performance in improving the properties of asphalt binder and asphalt mixture.