Substituição parcial e total do agregado miúdo por resíduo de scheelita na produção de pavers.

Abstract

Civil construction offers numerous environmental impacts, mainly due to the unbridled extraction of natural resources. Thus, finding materials that at first do not have an adequate final destination, such as mining waste, to replace all or part of the inputs used in the production of concrete, would be a viable solution from the environmental point of view, since it would directly solve problems such as reducing the removal of raw materials in the environment and the final destination of waste residues generated by mining activities. Among the minerals extracted in Brazil, scheelita stands out for moving a large part of the economy, mainly in the state of Rio Grande do Norte, and for generating a large monthly volume of waste, added to its beneficiation process. Thus, this work aims to evaluate the partial and total replacement of the conventional fine aggregate used for the production of concrete pieces, sand, by scheelite residue, in the proportions of 10%, 25%, 50% and 100%, analyzing its technical feasibility through tests used in the standard of concrete parts for paving, ABNT NBR 9781/2013. For the submission of tests, all concrete pieces underwent a curing process for 28 days. From the results found, it was observed that in the dimensional evaluation test, all pavers were within the requirements by rule. Regarding the water absorption test, only as compositions of 25% and 50% of scheelite not known in accordance with the limits stipulated by norm. For the characteristic compressive strength test, no composition was able to achieve the minimum strength of 35 Mpa required by the standard for traffic level. However, all similar compositions have similar results, with emphasis on a composition of 10% scheelite that presented the best results in all tests. Therefore, it appears that the use of scheelite in the production of pavers is a promising solution, considering that its use provides savings, reduces the extraction of sand in the environment and offers a final destination of this waste, promoting sustainability and a good relationship between civil construction and the environment.