Mining Publication: Pillar Strength in Underground Stone Mines in the United States
Original creation date: January 2011
Stone mines in the Eastern and Midwestern United States make use of the room-and-pillar method of mining to extract relatively flat-laying sedimentary formations. A survey of pillar performance was carried out to identify potential modes of instability. Pillars were found to have been successful in providing support to the overburden, but a small number of individual failed pillars were observed. Failure of the pillars was observed to be related to spalling of the hard brittle rocks, shearing along pre-existing angular discontinuities or progressive extrusion of soft infill materials on bedding planes. A method of estimating the pillar strength and selecting a safety factor for design was developed based on observations of stable and failed pillars, supplemented by numerical models. The developed pillar strength equation can be used to design stable stone mine pillars provided the rock conditions are similar to those included in the study.
Authors: GS Esterhuizen, DR Dolinar, JL Ellenberger
Peer Reviewed Journal Article - January 2011
NIOSHTIC2 Number: 20038279
Int J Rock Mech Min Sci 2011 Jan; 48(1):42-50
See Also
- Analysis of Pillar Design Practices and Techniques for U.S. Limestone Mines
- Effect of the Dip and Excavation Orientation on Roof Stability in Moderately Dipping Stone Mine Workings
- Field Observations and Numerical Studies of Horizontal Stress Effects on Roof Stability in U.S. Limestone Mines
- Pillar and Roof Span Design in Stone Mines
- Pillar Design
- Pillar Design Issues for Underground Stone Mines
- Pillar Stability Issues Based on a Survey of Pillar Performance in Underground Limestone Mines
- Pillar Strength and Design Methodology for Stone Mines
- Rock Falls
- Roof Span Design for Underground Stone Mines
- Roof Stability Issues in Underground Limestone Mines in the United States
- Toward Pillar Design To Prevent Collapse of Room-and-Pillar Mines
- Content source: National Institute for Occupational Safety and Health, Mining Program