Properties of Superpave Asphalt Concrete Subjected to Impact of Moisture Damage

Abstract

Moisture damage is a primary mode of distress occurring in hot mix asphalt (HMA) pavements in Iraq. Because of the loss of bond, or stripping, caused by the presence of moisture between the asphalt and aggregate, which is a problem in some areas and can be severe in some cases, it is requires to evaluate the design asphalt mixture to moisture susceptibility. Many factors such as aggregate characteristics, asphalt characteristics, environment, traffic, construction practices and drainage can contribute to stripping. Asphalt concrete mixes were prepared at their optimum asphalt content by superpave system and then tested to evaluate their engineering properties, which include tensile strength, resilient modulus, and permanent deformation, stiffness, and fatigue characteristics. These properties have been evaluated using indirect tensile strength, uniaxial repeated loading and repeated flexural beam. The experimental results, in general, showed that the mixes subjected to moisture damage give low resistance to indirect tensile strength, low resilient modulus at 40 ̊ C, high permanent deformation at 40 ̊ C, low stiffness, and low fatigue life, by (19%, 21%, 93%, 62% and 70%) respectively as compared with unconditioned mixture.