eva‎luation of Moisture Sensitivity of Asphalt Mixtures containing APAO using Surface Free Energy Prameters

7/11/2023 12:00:00 AM

This study investigated the effect of Amorphous Poly Alpha Olefin (APAO) on the rheological behavior of bitumen and the moisture sensitivity of asphalt mixtures. In order to modify the bitumen, additives with percentages of 0, 2, 4, 6, 8 and 10% by weight of bitumen have been used. In this research, the degree of penetration, softening point, ductility, viscosity, contact angle and Wilhelmi plate on bitumen as well as Marshall Strength test, indirect tensile strength, boiling water and rotating container on asphalt mixtures have been performed. According to the results, the use of APAO reduces the degree of penetration and increases the softening point, which may be due to the hardening of the bitumen. PI values increased with the addition of APAO, which showed that the temperature sensitivity of all modified asphalt samples decreased compared to the initial bitumen. Increasing the viscosity of the initial bitumen due to the addition of APAO made the compaction operation more difficult. Three liquids (distilled water, glycerol and ethylene glycol) were used to obtain the surface free energy parameters. Increasing the APAO increased the adhesion and cohesion of the bitumen and reduced the angle of contact of the liquid with the bitumen, thus increasing the surface free energy parameters. We also received the results of moisture sensitivity tests (Marshall Strength test, indirect tensile strength, boiling water and rotating container) which had a good performance in the process of degradation of moisture sensitivity.

انرژي آزاد سطحي , مخلوط هاي آسفالتي , حساسيت رطوبتي

surface free energy , APAO , moisture sensitivity

mohammad sabouri

phd hasan ziary