INHIBITION OF MICROBIAL SULFATE REDUCTION BY MOLYBDATE

Predicting and analyzing the stability of underground stopes is critical for ensuring worker safety, reducing dilution, and maintaining operational efficiency in mining. Traditional stability graphs are widely used but often criticized for oversimplifying the stability phenomenon and relying on subjective classifications. Additionally, the imbalanced nature of stope stability datasets poses challenges for traditional machine learning and statistical models, which often bias predictions toward the majority class. This study proposes a novel methodology for developing site-specific stability graphs using probabilistic modeling and machine learning techniques, addressing the limitations of traditional graphs and the challenges of imbalanced datasets. The approach includes rebalancing of the dataset using the Synthetic Minority Over-Sampling Technique (SMOTE) and feature selection using permutation importance to identify key features that impact instability, using those to construct a bi-dimensional stability graph that provides both improved performance and interpretability. The results indicate that the proposed graph outperforms traditional stability graphs, particularly in identifying unstable stopes, even under highly imbalanced data conditions, highlighting the importance of operational and geometric variables in stope stability, providing actionable insights for mine planners. Conclusively, this study demonstrates the potential for integrating modern probabilistic techniques into mining geotechnics, paving the way for more accurate and adaptive stability assessment tools. Future work includes extending the methodology to multi-mine datasets and exploring dynamic stability graph frameworks.

O monitoramento de escavação é uma forma concisa de avaliar o desempenho operacional do desenvolvimento de uma galeria através do acompanhamento dos índices de overbreak, underbreak e a qualidade da escavação. Ao iniciar o desenvolvimento das galerias subterrâneas os fatores não controláveis intrínsecos ao maciço rochoso devem ser avaliados de modo que as falhas operacionais peculiares ao processo sejam minimizadas, principalmente, na execução das atividades de marcação topográfica das frentes e perfuração horizontal. Para garantir melhor controle, tornar mais confiáveis às medições dos índices, realizou-se uma retroánalise dos levantamentos das escavações da Mineração Caraíba S/A, determinando os índices de overbreak e underbreak, a qualidade das escavações e correlações entre a razão de carregamento e os indícios foram investigados.