Evaluation of the impact of moisture damage on warm mix asphalt containing zeolite and hydrated lime.

One of the most frequently acknowledged causes of premature cracking in Warm Mix Asphalt (WMA) is moisture damage. Pavement tension caused by deteriorating moisture results in irreversible deformation, flaking, raveling, fatigue damage, and strength loss. This study investigated the impact of hydrated lime (HL) with the incorporation of zeolite, a foaming agent, on the moisture sensitivity of a Warm-Mix Asphalt (WMA) composition, considering both manufactured and natural formulations. Furthermore, hot mix asphalt is produced within three temperature ranges of 120, 130, and 140 degrees Celsius, including 160 degrees Celsius. WMA mixtures are manufactured with Iraqi resources in mind; one type of aggregate and one binder grade (40/50 pen) are obtained from Durah refinery plant. Specific evaluations were performed on every mixture, encompassing indirect tensile strength (ITS), Marshall characteristics, and moisture damage of bitumen mixtures as measured by tensile strength ratio (TSR). The experimental results demonstrated that the properties of the heated bitumen mixture were influenced by the type of zeolite incorporated. The combination of WMA and 5% fixed natural zeolite produced the highest Marshall stability, flow, ITS, and TSR values at all temperatures. The sample denoted as Hydrated Natural Zeolite (H-N-Z) exhibited the lowest Marshall Stiffness Index (MSI) values among all specimens, followed by Hydrated Synthetic Zeolite (H-S-Z) and WMA with added water. [ABSTRACT FROM AUTHOR]