The incorporation of reclaimed asphalt pavement (RAP) into asphalt mixtures exposes some challenges from the design perspective because of the aged asphalt binder in RAP. Steps are being taken to offset the addition of stiff materials, often with the use of rejuvenating additives. This paper summarizes the laboratory evaluation of one of the available bio-rejuvenating agents called BituTech RAP. High RAP content mixtures used in Manitoba, Canada, were evaluated to study the impact of BituTech RAP on the viscoelastic properties of asphalt mixtures to overcome any possible moisture damage or thermal cracking problems that might arise in such a wet–freeze environment. The laboratory experiment consisted of the production and test of mixtures that contained 15% and 50% RAP, with and without BituTech RAP. The 2S2P1D analogical model was used to generate the complex modulus (E*) of the various evaluated mixtures and to assess the influence of BituTech RAP on the storage and loss moduli. The addition of BituTech RAP improved the moisture resistance of the mixtures that contained RAP, as observed after three freeze–thaw cycles. The addition of BituTech RAP restored the thermal cracking properties of the mixtures revealed by the thermal stress restrained specimen test. The use of BituTech RAP could result in cost savings without the need to use a softer binder, as long as the high-temperature properties of the mixtures were not jeopardized.

Sustainability at airports has received attention recently as owners have worked to incorporate sustainable practices into projects and daily operations. Several guides have been published by airport agencies to document sustainable practices. One potential practice involves alternative paving materials for airfield pavements. Specifically, fiber-reinforced asphalt concrete has shown promising results and has recently been used to resurface Runway 1–19 at the Jackson Hole Airport in Jackson, Wyoming. This paper explores the feasibility of using fiber-reinforced asphalt concrete as a sustainable paving strategy for airfields. The study includes an extensive literature review, performance testing of an asphalt mixture, cost analysis, a sustainable credit summary, and a carbon dioxide emission comparison. Laboratory testing showed that the Jackson Hole Airport mixture performed better than a control mixture produced in the laboratory with similar materials. Further analysis concluded that a fiber-reinforced, porous asphalt friction course could qualify for several sustainable site credits. In addition, the minimal upfront cost of fibers makes this product attractive because the cost can be recouped by an approximate 1-year extension in service life. Pavement design simulations indicated a reduction in equivalent carbon dioxide emissions through the extension of service life. Recommendations for the use of fiber-reinforced asphalt concrete on airfields are provided based on the findings of this study and future research is identified.

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