A hybrid empirical-numerical framework for pillar stability and reinforcement in deep underground marble mines: a case study

This study developed a hybrid empirical-numerical framework to enhance pillar stability and reinforcement in deep underground marble mines, addressing the challenges posed by increasing depths where traditional methods falter. The purpose was to create a reliable, efficient tool for assessing and optimizing pillar stability, ensuring safety at depths up to ۳۰ meters. The methodology integrated empirical calculations, using the Obert and Duvall (۱۹۶۷) method, with FLAC۳D numerical simulations, employing a depth-dependent weighting system (α) to balance simplicity and precision. Data from seven pillars (P۱–P۷) was preprocessed, analyzed, and optimized through width adjustments (e.g., P۱ from ۳۰ m to ۶۰ m) and rock bolt reinforcement (۱.۸ m spacing). Findings revealed a decline in hybrid Factor of Safety (FOShybrid) from ۳.۵۹ at ۵.۵ m to ۱.۲۳ at ۳۰ m pre-optimization, rising to ۲.۱۸ post-optimization, meeting the safety threshold ۲.۰. Validation against empirical (e.g., ۳.۶۱۶ at ۵.۵ m) and numerical (e.g., ۱.۹۵ for P۶ at ۲۱.۵ m) FOS values, with R۲ > ۰.۹۵ And CV < ۱۵%, confirmed the framework’s accuracy. This hybrid approach significantly improved safety and efficiency, offering a scalable solution for deep mining. Future research could extend it to other rock types or incorporate real-time monitoring, enhancing its adaptability and impact.

کلیدواژه ها:

Pillar stability ، deep underground mining ، hybrid framework ، Empirical Analysis ، Numerical simulation ، reinforcement optimizations