Estudo das propriedades mecânicas de misturas asfálticas modificadas com adição do óleo de milho.

Abstract

The search for more efficient production processes of asphalt paving has led studies to evaluate the capability of reducing the temperature at which hot mix asphalt (HMA) is produced and compacted without compromising the performance of the pavement. In this scenario, the warm-mix asphalt (WMA) technology is an alternative to decrease the production of greenhouse gases besides cutting fuel consumption. Additions of organic additives derived from oilseeds on asphalt binders can change its viscosity-temperature behavior, reaching reductions in temperatures of mixing and compaction of the asphalt mixtures. The corn production is the most significant grain crop in Brazil. Its oil is one of the most widely consumed for cooking purposes. However, when the afterconsumption oil is incorrectly discarded, generates environmental impacts. Therefore, the feasibility of inserting new and after-consumption (residual) corn oil in the asphalt binder was analysed and confirmed on rheological aspects. The present study aims to evaluate the effects of incorporating the SBS-modified asphalt binder with new and residual corn oil on mechanical properties of asphalt mixtures. To achieve this objective, the tests of Indirect Tensile Strength, Resilience Modulus, Modified Lottman, Dynamic Modulus and Flow Number were performed. The asphalt mixture samples were produced and compacted at the temperature obtained from the rotational viscosity test, as well as at 10 and 20 oC below it, in order to verify the mechanical response of further reductions on the production temperatures. The results show that the oil additions and the temperature reductions tend to reduce the asphalt mixtures maximum strength, stiffness and resistance to permanent deformation. These values, however, still meet the specifications for quality of the resulting pavement. Nonetheless, a greater care is required on the sensitivity to moisture of the asphalt mixtures studied. No interference of the frying process was observed regarding the analysed aspects, confirming the use of the residual oil, promoting an environmentally friendly dispose of this residue.