Use of recycled mixed aggregates in floor blocks manufacturing

Abstract

The roadmap proposed by the European Community states that construction and demolition wastes (C&DW) should be managed by 2020 as resources reincorporated into the production system as raw material. Within this framework, this study addresses the reuse of a type of waste that does not come from building demolition, as is usual, but from concrete and ceramic wastes generated by precast production facilities. The objective is to use mixed recycled aggregates in order to reuse them in the production of new prefabricated elements. The study has focused on the production of concrete floor blocks used in slabs for the construction sector.In order to have practical information to make suitable decisions to use these precast pieces in the future, some experimental works have been carried out to evaluate the main mechanic properties of floor blocks for different percentages of replacement of natural aggregates with recycled ones. In addition, two replacement percentages (35% and 70%), not frequently used, have been considered in the research.The results show that these type of aggregates produce better results than those coming from demolitions waste. In fact, for substitution percentages below 35%, the decrease of mechanical strength is very small and, for a 100% of substitution, although there is a loss of resistance, the floor blocks satisfy the requirements of European standards.