In Spain, there is a growing interest in recycling bituminous pavements, for both technical and economic reasons. Of all possible procedures, on-site rejuvenating recycling is the one with the most future. Beforehand, a physical and chemical study is necessary to determine the characteristics of the ageing binder as well as to develop the new ones. This paper presents the application of the technology developed by the Repsol for two recycling projects carried out in Spain. Based on a chemical analysis of the bituminous extracts of the ageing pavement, the most adequate characteristics of the rejuvenating product are determined. Then an emulsion is formulated based on the former product, so as to keep to a minimum the total amount of water from compaction of the ageing pavement mixture. Finally, laboratory tests establish the mechanical features of the new mixture,and the optimal emulsion content is chosen. Implementing these recycled mixtures has been problem-free, and excellent results have been obtained in the two projects where this type of technology has been applied. (A)
Abstract