Development of a GUI-based Educational Tool for the Comparison of Pillar Design Models in Underground Mining

Abstract. The room-and-pillar method is one of the most widely used underground mining methods owing to its simplicity, safety, and low cost. Pillar design is fundamental to ensure operational stability and increase ore recovery. In recent decades, various empirical formulas have been developed to estimate pillar strength under different geometric and geomechanical conditions, each considering specific conditions of application and presenting a series of limitations. This study presents a Python-based educational software tool with a graphical user interface (GUI), designed to support the teaching and preliminary analysis of empirical pillar-design models in underground mining. The tool integrates tributary area theory, equivalent width calculation, pillar strength estimation, safety factor, and extraction ratio assessment within an interactive environment. Several empirical and semi-empirical models, including Lunder-Pakalnis, Hedley-Grant, Salamon-Munro, Krauland-Soder, Sjoberg, Laubscher, Hoek-Brown, González, USBM, Bieniawski and user-defined equations, are implemented to allow systematic comparison under identical input conditions. In addition, the software provides graphical visualization, automatic critical model identification, and parametric analyses of the safety factor as a function of We/h, including the associated extraction ratio to reach a target safety factor. A case study is presented to demonstrate how the tool helps students and instructors explore the variability, applicability, and limitations of empirical design equations. The results show that the software can simplify the conceptual understanding of pillar stability, model selection, and the trade-off between safety and extraction in room-and-pillar mining. The tool is intended for educational and preliminary engineering purposes and can be used in courses related to underground mining, rock mechanics, and mine design.