Characterization of hot-mix asphalt made with recycled concrete aggregates that have been cured for 4 hours in the oven

Abstract

[Abstract:] In this research a laboratory characterization of hot-mix asphalt (HMA) made with recycled concrete aggregates (RCA) from construction and demolition waste (CDW) as base layer in road construction has been conducted. HMA containing 5%, 10%, 20% and 30% of RCA in place of virgin aggregate were evaluated. To improve water resistance of the mixtures, they were left in an oven for 4 hours at mixing temperature before compaction to allow the bitumen absorption and, in addition, obstructing the mortar pores, strengthening the attached mortar onto the RCA surface and thus, preventing water pathways. The tested mixtures complied with Spanish water resistance requirement and also showed a water resistance performance much higher than that of the mixtures that were not cured in the oven. Stiffness and resistance to permanent deformation were also studied showing satisfactory results.