Basalt-Containing Pressed Cement Plates for Construction Systems: Technological and Toxicological Characterization

In recent years, industries have been demanded for better disposal methods of byproducts. In addition, civil construction in Brazil has been steadily growing, necessitating the development of new resources and the use of new materials. Thus, to reduce the environmental impact and costs, the use of byproducts in civil construction plays an important role. This study presents experimental results on the development of cementitious material-based plates for the construction system of panel slabs using powder technology to reduce the amount of concrete in the slab. In this study, sand was partially (58.1% by weight, C3) and totally (C1) replaced by basalt powder, a byproduct of the basaltic rock beneficiation process. Cementitious plates were obtained by uniaxial pressing at different compaction pressures. The moulded plates (M) using sand and cement were obtained as references. The bending strength at 28 days of curing was $2.50\pm 0.10\mathrm{MPa}$, which is higher than that of the moulded plates ($1.94\pm 0.11\mathrm{MPa}$). It was concluded that pressing and sand substitution by basalt reduced the linear expansion from $0.059\%\pm 0.003\%$ (M) to $0.042\%\pm 0.007\%$ (C3), reducing the risk of cracking. The evaluation of the environmental impact showed the potential of replacing sand with basalt, thus reducing the cost of the material. Therefore, pressed plates with the total substitution of sand by basalt achieved better results related to the moulded plates and demonstrated considerable potential for application in the civil construction industry.