Influence of treatment methods on the bond strength of recycled aggregate concrete

Scarcity of natural coarse aggregate has initiated the use of recycled aggregate obtained from crushed concrete rubbles in building industry. The quality of recycled aggregate concrete (RAC) produced depends on the quality of recycled aggregate obtained from old concrete. Several methods such as acid treatment, thermal treatment, mechanical treatment, etc. are available to improve the quality of recycled concrete aggregate. This paper aims to compare the effect of treatment methods on the bond strength of reinforcement with concrete. Fifteen numbers of RILEM beam specimens are prepared using natural aggregate, untreated recycled aggregate, recycled aggregate treated with acid, mechanical and thermal methods. The physical, mechanical properties of these aggregates, their compressive strength and bond strength are determined and the optimum results are presented in this paper. (C) 2016 Elsevier Ltd. All rights reserved.