Utilizing Construction and Demolition (C&D) Waste as Recycled Aggregates (RA) in Concrete

Abstract

Construction and Demolition (C&D) waste constitutes a major portion of total solid waste production in the world, and most of it is used in landfills. Research by concrete engineers has clearly suggested the possibility of appropriately treating and reusing such waste as aggregates in new concrete, especially for lower level applications. This study discusses recycled aggregates (RA) produced from C&D waste and their use in concrete construction. Along with a brief overview of the engineering properties of recycled aggregates, the study also gives a summary of the effect of recycled aggregates on the properties of fresh and hardened concrete. Recycled aggregates are treated with epoxy resin to reduce the water absorption. This research, however, shows that the recycled aggregates that are obtained from site-tested concrete specimen make good quality concrete. The influence of aggregates of varying sizes on the compressive strength, split tensile and water absorption of concrete is presented in this paper. Recycled aggregate concrete was in close proximity to normal concrete in terms of split tensile strength and compressive strength. The slump value of recycled aggregate concrete was low and that can be improved by using saturated surface dry (SSD) coarse aggregate.