IMPROVING ADHESION CHARACTERISTICS OF BITUMINOUS MIXES BY WASHING DUST-CONTAMINATED COARSE AGGREGATES

Whether the engineering characteristics of bituminous mixes (especially their resistance to moisture effects) can be improved by washing the coarse aggregates and mixing the coarse and fine aggregates separately has been investigated. Results indicated that the washing of the coarse aggregate was most effective with the weaker aggregate. Washing the coarse aggregates generally improves the strength characteristics and reduces the asphalt content required to attain a certain level of strength, density, and air voids.