Archived
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Author ORCID Identifier
Date Available
4-14-2026
Year of Publication
2026
Document Type
Master's Thesis
Degree Name
Master of Science in Mining Engineering (MSMIE)
College
Engineering
Department/School/Program
Mining Engineering
Faculty
Zach Agioutantis
Faculty
Steven Schafrik
Abstract
The objective of this thesis is to strengthen the relationship between empirically based stone pillar design methods and two numerical modeling techniques by calibrating boundary element and finite element models to the S‑Pillar empirical criteria and observed pillar behavior in underground stone mines. The first component of the research investigates the displacement‑discontinuity boundary element method implemented in LaModel, quantifying the influence of the lamination thickness and element size on stone pillar safety factor predictions. Results showed that optimal thickness depends on overburden modulus, while larger element sizes introduce significant SF differences from S-Pillar values once the grid size exceeds 5 ft. The second component focuses on finite element modeling of brittle stone pillars in RS2 using a Hoek–Brown based material model following the Damage Initiation Spalling Limit approach. Peak strength errors were kept below 8% across the modeled width‑to‑height range, and the simulated failure patterns were consistent with field observations. The work provides quantitative guidance on lamination thickness and element size selection for LaModel stone pillar analyses and proposes calibrated Hoek–Brown parameter sets for RS2 that allow practitioners to perform continuum finite element analyses aligned with both the S‑Pillar empirical database and current understanding of brittle spalling behavior.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2026.46
Archival?
Archival
Funding Information
This work was supported by the Alpha Foundation for the Improvement of Mine Safety and Health, through Grant No. AFCTG22r2-160 in 2025 & 2026.
Recommended Citation
Diddle, Benjamin, "LINKING S‑PILLAR EMPIRICAL CRITERIA WITH BOUNDARY AND FINITE ELEMENT MODELS FOR UNDERGROUND STONE PILLAR ANALYSIS" (2026). Theses and Dissertations--Mining Engineering. 95.
https://uknowledge.uky.edu/mng_etds/95
