Improving the performance of porous asphalt with reclaimed asphalt, dune sand and lime

A porous asphalt pavement is an open-graded asphalt mix that allows rainwater to drain through the surface layer. When designing a pavement structure, the porous asphalt layer is generally not taken into consideration due to its poor mechanical characteristics. The objective of this research study was to reuse reclaimed asphalt pavement in a porous asphalt mixture and then to improve the performance of the resulting mix by adding dune sand and lime. Several porous asphalt mixes with the addition of different percentages of reclaimed asphalt, dune sand and lime were tested. The results obtained showed an improvement in the mechanical performance of the tested porous asphalt mixes, especially when using 40% reclaimed asphalt, 10% dune sand and 1% lime. Marshall stability and Duriez compressive strengths increased when compared to the values obtained with a reference porous asphalt mixture, by 42 and 66%, respectively, while the flow decreased by 30%. In addition, except for the splitting tensile strength, all other studied mechanical characteristics were better than those of the ordinary well-graded hot-mix asphalt.