Multirecycled concrete aggregates in concrete production

Abstract Because using recycled aggregates (RAs) in concrete production becomes a standard practice, a new problem arises: how do the RAs produced from concrete made itself with RAs behave? Moreover, how does the recurrence of this produce-recycle in concrete affect the performance of the newer aggregates and of the concrete mixes made with them? In the following chapter, the effects of recycling of concrete consecutively on the performance of the derived RAs and on the concretes made with them are discussed. The physical and morphological properties of the RAs were determined using state-of-the-art techniques, and every study seems to conclude that there are threshold limits to the decrease of the properties of these aggregates as the number of recycling cycles increases. The same trend has been observed for the mechanical properties of concrete made with these same RAs, overall pointing to a general conclusion that multirecycling of concrete is a viable solution to mitigate the existing environmental problems related to concrete production and demolition, but that it has some limitations, if overall quality is to be maintained.