Performance evaluation of porous asphalt with granulated synthetic lightweight aggregate

This paper presents the results of a laboratory study evaluating the mixture characteristics and durability of porous asphalt made with granulated synthetic lightweight aggregate (GSLA). Porous asphalt specimens incorporating 0%, 5%, 10%, 15% and 20% GLSA by volume as a coarse aggregate (retained on a No. 4 sieve) replacement were prepared. Test results indicating that GSLA exhibits well particle shape, lower specific gravity, higher soundness and higher water absorption than conventional crushed stone (CS) does. The mix design results showed that GSLA mixtures have high asphalt absorption due to porous nature of the GLSA as evidenced in scanning electron microscope (SEM) image. Compared with conventional CS mixtures in terms of skid resistance, permeability, particle loss resistance, moisture susceptibility and rutting resistance, the GLSA mixtures perform very favorably. The results show that the mixture of 15% GSLA replacement was determined to be the most suitable mixture.