Technological properties of soil-cement bricks produced with iron ore mining waste

Abstract

Soil-cement brick is a composite obtained by mixing soil, cement, and water in previously established proportions. This material is an alternative for urban or rural construction, as it offers several advantages for its use in masonry, such as the addition of waste. For the addition of waste into cement materials the waste from iron ore extraction process has been highlighted Thousands of tons of this waste are generated on a daily basis large mining companies, leading to air pollution and the occupation of large physical spaces. Thus, the aim of this work was to evaluate the effect of replacing different percentages (0, 10, 20, 30, and 40%) of soil by this mining waste on the properties of soil-cement bricks. The raw materials used were: soil (A-4 classification), CPV-ARI cement, and solid mining waste, which were characterized by physicochemical analysis. The mix ratio used for bricks production was 1:9 (cement:soil), where soil was replaced by different waste percentages. Technological properties such as: dry density, water absorption, immersion mass loss, compressive strength, thermal conductivity, and microstructure were determined. The results indicated that the added mining waste positively influenced the density of cement bricks in the soil. In addition, up to 40% of the waste could be incorporated into the brick, considering the current characterisation standards.