Comparative Analysis of the Rheological Properties of Asphalt Binders Modified by Vegetable Oils from Brazil

The utilization of oleic additives as modifiers for asphalt binder presents itself as a viable and environmentally friendly alternative. This study assessed the physical and rheological characteristics of asphalt binder, graded as penetration 50/70, modified through the inclusion of five vegetable oils (copaiba, cotton, linseed, soybean, and corn) at concentrations of 1% and 3%. The analyses, conducted both pre- and post-short-term aging (RTFO), encompassed Penetration, Softening Point, Rotational Viscosity, Performance Grade (PG), and Multiple Stress Creep Recovery (MSCR) tests. The findings indicated the suitability of soybean, copaiba, and linseed oils for warm mixtures, exhibiting potential environmental and energy advantages. Cotton, linseed, and soybean oils exhibited promising prospects for enhancing recycling in asphalt mixtures, with all modified binders meeting standard traffic requirements. The utilization of 3% of these vegetable oils stands out for its practicality, offering sustainable alternatives for pavement construction and the potential for cost reduction in production processes. Overall, soybean and linseed oils were noteworthy for their significant softening and stiffness-reducing effects on the binder.