Spent foundry sand to portland cement concrete: An aggregate analysis

Abstract

Spent foundry sand (ADF), one of the wastes from the process of manufacturing parts and components in foundries, is a material with a lot of silica from a mix with natural sand, thinner than natural sand and classified by the Brazilian standard NBR 10004 as waste class II A, non-hazardous and non-inert. An analysis of the ADF was carried out with the objective of its use in concrete because it has interesting physical characteristics to be used as a substitute of the natural fine aggregate in the production of Portland cement-based materials. After the morphological, physical and chemical analysis of the ADF, the use of ADF in Portland cement concrete was evaluated and the fresh performance (workability and fluidity) of these concretes was also tested in several substitution proportions. As final evaluation, mechanical and leaching tests were performed on the ADF concrete and the results indicated that there is loss of mechanical performance with the increase of the ADF content, but this loss can be considered small when compared with the environmental value of the use of the ADF As a substitute for the natural aggregate in the production of concretes.