EAPROVEITAMENTO DE ESTÉRIL DE MINERAÇÃO COMO AGREGADO GRAÚDO PARA FABRICAÇÃO DE CONCRETO.

Since mid-2014, the Brazilian construction sector has been facing a severe economic recession. However, the demand for raw materials for concrete production remains high, especially for aggregates. This is because approximately 70-80% of the concrete volume is made up of gravel and sand. It is estimated that 740 million tons of gravel and sand were consumed in Brazil by civil construction in 2014. However, in 2015 this same consumption was reduced to 519 million tons. The adoption of innovative raw materials with high quality, low price, and lower environmental impacts in its production chain is of paramount importance for increasing the sustainability in the construction sector. The aim of this work was to characterize physically and chemically waste rocks from mines located on the southeastern part of the Goiás state in order to use them as coarse aggregates for concrete. The technical standard NBR 7211/2009, published by the Brazilian Association of Technical Standards (ABNT) was used. Four samples of 100 kg were collected from different lithologies and classified by dry screening to obtain four different gravel types (0, 1, 2, and 3). Specific mass, compacted unit mass, water absorption, clay and friable material content, mechanical strength, fine material content, particle size distribution, and shape index were determined. All samples passed the tests and, therefore, the waste rocks has features that allow them to be used as coarse aggregates in civil construction. [ABSTRACT FROM AUTHOR]