A influência das estruturas de descontinuidades na lavra de rochas ornamentais e na avaliação de seu IAEG: uma análise de casos

Abstract

Ornamental rocks constitute a very important input for civil construction, being widely used as covering, decorative or structural functions, becoming a material widely produced in Brazil. Due to its high production, the broad recovery of this mineral asset is of great interest to the miner. It is essential, therefore, to know the causes that cause this material to have low recovery. One of these causes is the presence of discontinuities in the rock such as fractures, joints and foliation planes. These geological structures are involved from the previous research stage in defining the Economic-Geological Attractiveness Index (IAEG) to the mining stage, as the presence of these structures can lead to consequences such as the resizing of blocks to smaller dimensions, which reduces the mining profitability, as larger block sizes are more interesting for the market. The purpose of this research is to succinctly define the most common types of discontinuities in rock masses and their mode of formation, in addition to evaluating their influence on the planning and extraction of ornamental rocks. Furthermore, the aim of the second part of this work is to present cases in which geological structures interfered in some way in ornamental rock quarries, indicating their influence on the IAEG in each case and on the cutting of blocks in the mine. The analysis of information to fulfill these objectives was carried out through a narrative bibliographic review, seeking information in academic works on rock masses related to the mining of ornamental rocks, subsequently applying the IAEG index. With this, it was possible to conclude that although the presence of discontinuities in ornamental rocks sometimes harms their mining, depending on the characteristics of the rock and its processing location, these can compensate for the presence of fracturing.