Applying surface free energy method for evaluation of moisture damage in asphalt mixtures containing date seed ash

Present study deals with applying surface free energy theory in evaluating the possibility of using date seed ash as a bitumen modifier of hot mix asphalt mixtures against moisture damage. For this purpose, pure bitumen as well as ash containing samples was employed to produce mixtures having two different aggregate types (namely, limestone and siliceous). Prediction of surface energy was well supported by the laboratory method (AASHTO T-283) and proves the potential use of ash as a modifier. The achieved results indicated that using date seed ash will improve TSR of limestone and siliceous mixtures (i.e. 12.65% and 20%, respectively).