Correlations of rock mass classifications applied to ferruginous caves
AUTOR(ES)
Oliveira, Paula Leal; Lima, Hernani Mota de
FONTE
REM, Int. Eng. J.
DATA DE PUBLICAÇÃO
2020-06
RESUMO
Abstract For the Brazilian iron ore mines, the presence of caves presents a challenge, since most of them are located within the ore deposit. The National Environment Commission (CONAMA 347 Resolution/2004) establishes that the speleological heritage, as well as its area of influence, cannot sustain irreversible environmental impacts. The physical integrity of caves adjacent to mining operations is an issue of pivotal importance to be scrutinised in studies towards the delimitation of the cave’s protection radius. This article presents the study of various models of correlation between the RMR and Q systems used for the stability assessment of natural iron ore caves. In order to study a correlation between the RMR and Q systems, the most popular rock mass classifications, and their application as a validation tool, a selection of measurements of Q and RMR, organized in a database from seven natural caves of ferruginous lithology, are submitted to a study and statistical analysis. An empirical equation was obtained from the data, using a simple linear regression. The result of the regression was compared with selected correlation equations and the best fit for the data was chosen. The best fit was the Rutledge & Pearson correlation equation, which presented the best combination of R² and S, after the equation created on basis of the real values for RMR, though the other equations have results similar to it. As the results were quite similar, the recommendation still is that correlations should be used with caution, and associated to other methods and field analysis.
Documentos Relacionados
- Applicability of geomechanical classifications for estimation of strength properties in Brazilian rock masses
- Estimating the rock mass deformation modulus: A comparative study of empirical methods based on 48 rock mass scenarios
- Analytical solution of circular tunnel in elastic-viscoplastic rock mass
- Mass Balance Applied to Brazilian Conventional Broiler Houses during One Production Cycle
- Electrospray ionization mass spectrometry applied to study the radical acetylation of amino acids, peptides and proteins