Classification and characterization of recycled construction aggregate (RCA)

Construction projects use up large quantities of natural resources and produce tonnes of construction and demolition waste (CDW). Because of its growth, these quantities have increased in the last few years and it has now become necessary to create a sustainable method of development in civil construction. Therefore, recycling and utilization of recycled materials in construction projects can be the most promising solution for this problem. Due to important role and high portion of aggregates in asphalt concrete, utilization of recycled materials including recycled construction aggregates (RCA) can provide enormous benefits from the viewpoint of environmental sustainability and effective use of resources. In spite of the awareness of the importance of using RCA and much research being conducted, there is still a need for a deeper study about the characteristics of the RCA. The variability in behaviour and performance of RCA used in construction projects indicates the variability in their composition. This paper presents the results of a statistical study, image analysis and experimental study to evaluate the characteristics of RCA as an alternative for virgin aggregate in asphalt mixture. A series of characterization tests were conducted three times, using RCA collected at different dates.