Permanent Deformation and Moisture Induced Damage Potential of Stone Matrix Asphalt (SMA) Containing Barite Powder

The aggregate particles in asphalt mixtures get connected by (bitumen + mineral filler) mastic. The goal of this paper is to study the feasibility of partial and total substitution of Limestone (LS) filler by Barite powder (BP) in Stone matrix asphalt (SMA) mixtures. To evaluate barite powder performance, resilient modulus, indirect tensile strength, freeze-thaw cycles, dynamic creep at two different temperatures, and bitumen draindown tests were used. The obtained values revealed that an increase in barite powder content from ۵۰% to ۱۰۰% improved the Stone matrix asphalt mixture moisture performance by ۴.۵% after going through ۵ freeze-thaw cycles while on the other hand, it had an ۱۸.۵% reverse effect on the permanent deformation in higher temperatures. Also, despite barite powder's positive effect on bitumen draindown compared to the control samples; it could not yet thoroughly control SMA bitumen draindown.

Keywords:

Filler , Stone Matrix Asphalt (SMA) , Barite powder , Moisture Damage , Permanent Deformation