Effect of Addition of HDPE Pyro-Oil on Transition Temperature of Reclaimed Asphalt Binder

Sustainable development is a major global concern as it brings environmental as well as economic savings. Reclaimed asphalt pavement (RAP) has been gaining importance due to sustainability as well as its potential to perform well. Viscosity of asphalt binder plays an important role in determining the mixing and compaction temperatures. The aggregates should be satisfactorily coated during mixing and during compaction, and they should have enough mobility to form a compact aggregate matrix. The mixing temperature can be maintained constant but during compaction the temperature decreases as the process proceeds. Hence, it is necessary to study the rheological behaviour of asphalt binder at different temperatures as binder transits from non-Newtonian to Newtonian. In this study, VG30 has been used as a base binder. Samples have been prepared with 30 and 40% reclaimed asphalt (RA) binder by weight of base binder, termed as RAP30 and RAP40. Also 1% HDPE pyro-oil was added to evaluate the transition regime. A steady shear test was performed on the binders at different temperatures using a Brookfield Rotational Viscometer. The addition of RA binder increased the transition temperature, whereas the addition of HDPE pyro-oil resulted in a decrease in the transition temperature which leads to increase in critical shear rate.