RECYCLING OF CONSTRUCTION AND DEMOLITION WASTE AS AGGREGATE FOR PAVEMENT BLOCK PRODUCTION

Abstract

The objective of this paper is to evaluate the performance of recycled concrete aggregate for use in the production of pavement blocks. For this research project, aggregates were obtained from various sources of recycled waste, including wall plaster, ceramic tiles and concrete flooring. The concrete mixtures were prepared using three different quantities of recycled aggregate: 25%, 50% and 100% of the total aggregate weight. The structural properties of the concrete mixtures were analyzed using slump cone measurements and compressive strength tests (cube tests) at 3, 7 and 28 days. The results obtained indicated that the compressive strength of all mixtures increased with time. However, it was also noted that the compressive strength of the concrete mixtures decreased as the quantity of recycled aggregate increased. The maximum compressive strength was achieved at 28 days by the concrete mixture comprised of 25% recycled aggregate, which was obtained from concrete floor waste. This illustrates that the use of this type of recycled aggregate allows engineers to obtain concrete mix designs which meet the structural requirements for application in pavement blocks.