Influence of the amount of recycled coarse aggregate in concrete design and durability properties

Recycle construction wastage is the promising way towards sustainable construction. Recycled coarse aggregate (RCA) is the most common idea, but it does not gain wide acceptance among practitioners due the adhered mortar poses which deleterious effects on the concrete. However, a suitable concrete mix design enables the recycled aggregate concrete (RAC) to the achieve target strength and suitable for wide range of applications in construction. Insufficient knowledge on durability properties has also become a worry where applying RCA in construction is concerned. This paper is aimed to produce valuable information on the durability effects and design method for RAC. Parameters like compressive strength, ultrasonic pulse velocity (UPV), shrinkage, water absorption and intrinsic permeability were examined in this experiment. The results have revealed that the RAC exhibits a good UPV value, low water absorption and low intrinsic permeability. The target strength was achieved even when 80% of the total coarse aggregate content was replaced by the RCA and the mix design method proposed by the Department of Environment (DoE), United Kingdom was used.

► DoE mix design method is suitable for designing RAC.
► RAC exhibits low intrinsic permeability in later age.
► Up to 30% of RCA is advisable for insignificant deleterious effect.