Análise do uso de grãos da areia de britagem de origem granítica na produção de argamassas de revestimento

Abstract

Civil construction is responsible for a high level of environmental impact caused by the unconscious consumption of raw materials. Among the most depleted natural resources are river sands that have been replaced by sands from rock crushing. The use of this type of sand with appropriate procedures can be a viable alternative to replace natural sand in the production of coating mortar. In bibliographic references, information is found involving analyzes on the use of limestone and basaltic rock crushing sand and few involving granite rock areas of sand, a residue produced on a large scale in the southern region of Rio Grande do Sul, especially in extraction regions granite as Capão do Leão city. Considering these facts, in the present work the use of crushing sand of granitic origin was substituted in partial (50%) and total (100%) replacement of the natural sand of a mortar coating, produced with the 1: 1: 6 line (cement, lime, and sand, respectively). The analysis sought to verify the influence of the characteristics of granitic sand grains on the properties of coating mortars. The sands used were analyzed for granulometry, specific mass, unit mass, mineralogy, absorption, and shape of the grain. And, in mortars with natural sand and granite sand, the consistency index was analyzed in the fresh state and the hardened state, capillary absorption, resistance to axial compression, and tensile strength in flexion at three points. The results showed that the mortars with granitic sand presented greater absorption by capillarity and, also, higher values of mechanical resistance when compared with the mortar of natural sand, indicating that the angular shape of the granitic grain interfered in the analyzed properties.