Sustainability issues of asphalt rubber pavements

Abstract

Asphalt rubber (AR) mixtures constitute an alternative to traditional hot mix asphalts (HMA), especially when considering the following characteristics: higher fatigue and higher reflective cracking resistance; noise reduction and higher friction, in these later when suitable aggregate gradations are used. However, besides these apparently sound results, a holistic approach to the associated sustainability issues should be made, considering the pavement life cycle. The work undertaken included the comparison of the AR and HMA, regarding the following parameters: (i) structural performance; (ii) life cycle analysis; (iii) environmental evaluation of greenhouse gases emissions. The results allow concluding that AR mixtures present advantages in terms of performance and emissions, although the costs of those mixtures are higher than conventional mixtures. Nevertheless, more research is needed to evaluate the life cycle performance, including the reduction of the production temperature in order to obtain more economically and environmentally sustainable mixtures.