Environmental Improvement in Use of Fine Fraction Recycled Aggregates as a Raw Material in Masonry Mortar Fabrication

Great use of raw material and natural resources as well as generation of huge amount of waste make the construction and building sector one of the less sustainable human activities.

The main aim of this research is to study both technical feasibility and environmental sustainability of fine fraction recycled aggregates (RA) use in masonry mortar fabrication. Method. The tests were developed using the binder CEM IV/B (V) 32.5 N and two types of RA: ceramic RA and concrete RA. The substitution percentages were 50%, 75% and 100% and cement-to-aggregate by dry weight proportions were 1:3 and 1:4.

Performed tests show that cement-based mortars fabricated with CEM IV/B (V) 32. 5 N can incorporate concrete and ceramic recycled aggregates, using both cement-to-aggregate proportions, complying with the limits established by the Spanish standards. On the other hand, carbon footprint calculation of one of the RA used in the research and a comparative study with natural aggregate (NA) carbon footprint were carried out to analyze environmental sustainability of fine fraction RA. Conclusion. The results show that the amount of kgC_o2eq released into the atmosphere as a result of RA fabrication is significantly lower compared with the emissions from NA fabrication, and therefore the use of this type of waste reduces greenhouse gas emissions.