President, PRI Asphalt Technologies, Inc., Tampa, FL
Pages: 21 Published: Jan 1993
A low cost (less than domestic cellulose fibers), commercially available recycled asphalt roofing material, ReACT's HMA™ 2, with a uniform gradation (minus No. 20 sieve, plus No. 70 sieve), was evaluated as an additive in conventional dense-graded hot mix asphalt designs to assess the overall efficacy. Additionally, these same materials were pre-blended with neat asphalt cement binders to assess their applicability in Stone Mastic Asphalt mix designs. It was hypothesized the components of asphalt roofing materials, if properly processed/recycled, would interact synergistically with the asphalt pavement binder and aggregate to yield results similar to current in-use modifiers and additives, such as polymers, cellulose fibers, mineral fillers, and low-penetration natural asphalts. Field trials indicate the recycled asphalt roofing materials can be processed into conventional hot-mix asphalt designs, much like recycled asphalt pavement (RAP). Results of experimental mix designs indicated neat asphalt savings of up to 50% are achievable. Experimental mixes exhibited improved high-temperature susceptibility and rut resistant properties, while allowing for total binder contents up to 7–8 weight percent. Evaluation of recycled asphalt roofing material pre-blended with neat asphalt cement indicates these materials are a functional equivalent to currently used binder modifiers, and their successful use in stone mastic asphalts is highly probable. Overall, the recycled asphalt roofing materials are multi-functional in pavement mixtures, and their use can both alleviate environmental landfill concerns and result in cost-effective improved pavement designs.
asphalt roofing waste, stone mastic asphalt, Marshall Properties, SHRP Bending Beam Rheometer, drain-down, asphalt modifiers, rut resistance, recycling, environmental
Paper ID: STP19849S