Integrating Empirical and Numerical Models to Develop Stability Tools for Crown Pillars in Sublevel Open Stoping
Source abstract
Abstract
The design of near-surface crown pillars involves the interaction between excavation geometry, rock mass quality, and the in situ stress state. This study proposes a formulation that integrates numerical modeling and empirical criteria to construct a unified framework for stability interpretation. The Modeled Span index is introduced as a hybrid measure that incorporates geometric relationships and the pre-mining stress state, which, when compared with rock mass quality, allows the definition of a probabilistic stability boundary. The results show that the design tool enables the establishment of a consistent classification within the domain represented by the dataset. The Modeled Span chart complements traditional stability assessment approaches and is intended for application in conceptual and prefeasibility studies of crown pillars in Sublevel Open Stoping mining.
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Research context
OpenAlex topics: Mining Techniques and Economics · Rock Mechanics and Modeling · Tailings Management and Properties
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Affiliations
Department of Mining Engineering, Faculty of Engineering, University of Atacama, Copiapo 1531772, Chile
Department of Mining Engineering, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago 8370448, Chile
Advanced Mining Technology Center (AMTC), University of Chile, Santiago 8370448, Chile
Funding
Advanced Mining Technology Center
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