Fiber Elastomer Modified Asphalt for the Development of Resilient Porous Asphalt Mixtures

Heavy rain is one of the extreme weather events which pose a variety of serious risks on transportation infrastructures. Porous asphalt pavement can be used as a sustainable solution to mitigate the effects of such heavy rains. The objective of this study was to study the potential of using fiber elastomer modifier (FEM) to produce porous asphalt mixtures of high quality and enhanced performance. This was done through an experimental program composed of three different phases. The first phase was the development and the rheological, chemical, and microstructural characterization of the FEM modified asphalt. The second phase focused on using FEM to produce porous asphalt mixtures using different techniques. The third phase was the characterization of the porous asphalt mixtures to study their anticipated performance. The FEM asphalt performance grade, PG (76-22), proved enhanced rheological properties in terms of better rutting resistance indicated by higher G*/sin δ over a wide range of temperatures and lower J nr3.2 value of about 19% compared to the virgin asphalt and an enhanced fatigue cracking resistance manifested by the significant reduction in the fatigue cracking indicator G* sin δ with about 94%. Finally, porous asphalt mixtures were produced of an enhanced performance based on the dynamic modulus. Higher E* values at higher temperatures/lower frequencies and lower E* values at lower temperatures/higher frequencies were reported for the FEM porous asphalt mixture in reference to the, control dense-graded HMA mixture, promising an enhanced both rutting and fatigue resistances of the produced porous asphalt mixtures.