Enhancing the durability properties of concrete prepared with coarse recycled aggregate

It is generally known that the use of recycled aggregates in concrete would reduce its compressive strength and render the concrete less durable. Various methods have been attempted to compensate for the lower quality of the recycled aggregates for concrete production. In this paper, the effects of incorporating Class F fly ash in the concrete mix design to mitigate the lower quality of recycled aggregates in concrete is presented. The results show that one of the practical ways to utilize a high percentage of recycled aggregate in concrete is by incorporating 25-35% of fly ash since some of the drawbacks induced by the use of recycled aggregates in concrete could be minimized.