The effect of adding carbon nanotubes on rutting resistance of the asphalt containing modified bitumen by SBS polymer
Behzad Mehdipour1, Hasan Divandari, Hasan Taherkhani
One of the important and major defects seen in asphalt pavement is rutting or permanent deformation. Given the recent reports, millions of dollars are paid for repairing rutted pavements.The only solution for this problem is to evaluate the mixture quality in design stage. In present work, the prediction of asphalt mixtures behavior was studied using additives and such a behavior was related to one of rapid pavement test tools (wheel track). Uniaxial dynamic creep test was employed to evaluate mixtures behavior versus iterated load as well as to find creep parameters and to specify flow number in asphalt samples. In recent decades, the polymer and nanoparticles are widely used to modify the bitumen used in road pavements so that using modified bitumen in the asphalt, road construction executives have significantly increased service life of roads and thereby improved the operational life of them. The bitumen used in asphalt mixtures composes a very low weight value of this mixture (4-6%) but has a considerable effect on the asphalt efficiency. In this study, SBS polymer (as a modifier of thermoplastic elastomer with diverse weights (4-6%)) was mixed with MWNT carbon nanotubes having 1-3% weights and 60-70 bitumen of Tehran refinery and the corresponding effect was studied on diverse properties of asphalt mixtures. Conducting dynamic creep and wheel track tests, adding nanotube was found to have a significant impact on rut depth reduction and rutting strength increase.