Creep Behavior of SMA Mixtures with Slag and Polyethylene Terephthalate

Nowadays on the one hand improving the performance of asphalt mixtures is a necessity and on the other hand disposal of steel slag and plastic containers causes serious environmental problems. Therefore, in this study the effect of two waste materials on enhancing creep performance of Stone Mastic Asphalt (SMA) mixture was investigated; In order to thoroughly investigate the impact of Polyethylene terephthalate (PET) modification, specimens with three percentages of PET (3,5 and 7) in two forms (PET particles and PET fibers) were prepared. It was found that cumulative permanent strain was the lowest for specimens modified with 5 percent PET followed by 7 and 3 percent, respectively; Furthermore, adding PET in the form of fiber is more effective. With increase in stress and temperature, differences between creep performance of modified and unmodified samples were more prone. Based on average damage ratios, slag samples with 5 percent PET fiber (S-5P-F) were 70 percent less damaging.