Laboratory evaluation of stabilizing methods for porous asphalt mixtures

The objective of this study was to compare the performance of different stabilizing additives (cellulose fibers, styrene-butadiene-styrene [SBS], and crumb rubber modifier [CRM]) in a porous asphalt mixture. The mix evaluation was based on draindown, permeability, abrasion resistance, moisture susceptibility, and rutting. The results emphasized the importance of stabilizing additives in porous asphalt mixtures. Further, the results indicated that the addition of fibers or CRM were the most effective at minimizing draindown; CRM or the combination of fibers and SBS were the most effective at increasing the abrasion resistance; and the fibers had no effect on the mix strength.