Construction and demolition waste as recycled aggregate for environmentally-friendly concrete paving

Recycled aggregates (RA) from construction and demolition waste (CDW) instead of natural aggregates (NA) was analysed in the manufacture of new eco-friendly concrete. Fine (FRA) and coarse (CRA) recycled aggregates were used in different percentages as substitutes of natural sand and gravel, respectively. The results revealed that the use of RA in percentages of up to 50 wt.% are feasible. Additionally, RA were used to produce paving blocks in accordance with industrial requirements. Thus, values of water absorption lesser than 6% and tensile strength upper than 3.6 MPa were obtained, which are similar to those of a reference sample. These results were achieved by reducing the incorporation of cement, thereby saving production costs and minimizing environmental impact.This research has been partially supported by the Centre for the Development of Industrial Technology (CDTI) to the Spanish Ministry of Economy, Industry and Competitiveness (MINECO), by the project “Eco-efficient concrete urban paving from mixed recycled aggregates obtained from RCD” (Ref.: IDI-20180931). This research has been partially supported by RENSMA (Research Centre for Natural Resources, Health and 451 Environment), University of Huelva, Spain