Mining Product: Pillar and Roof Span Design Guidelines for Underground Stone Mines
Original creation date: May 2011
Underground stone mines in the United States use the room-and-pillar method of mining in generally flat-lying bedded formations. Pillar and roof span stability are two essential prerequisites for safe working conditions in room-and-pillar mines. Unstable pillars can result in rock sloughing from the pillar and can lead to the collapse of the roof if one or more pillars should fail. In addition, the roof span between pillars must be stable to provide safe access to the working areas. Falls of ground from the roof and pillar ribs account for about 15% of all lost working days in underground stone mines [MSHA 2009]. In the past, pillar and roof span dimensions were largely based on experience at nearby mines, developed through trial and error or designed on a case-by-case basis by rock engineering specialists. This document presents the results of research conducted by the National Institute for Occupational Safety and Health (NIOSH) in cooperation with participating underground stone mines to develop generally applicable guidelines for designing stable pillars and roof spans in stone mines.
Authors: GS Esterhuizen, DR Dolinar, JL Ellenberger, LJ Prosser
Information Circular - May 2011
NIOSHTIC2 Number: 20039529
Pittsburgh, PA: U. S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2011-171, IC 9526, 2011 May; :1-64
See Also
- A Computer Software Program that Estimates Air Quantity Requirements in Large Opening Stone Mines
- Controlling Roof Beam Failures From High Horizontal Stresses in Underground Stone Mines
- Effect of the Dip and Excavation Orientation on Roof Stability in Moderately Dipping Stone Mine Workings
- Effects of Weak Bands on Pillar Stability in Stone Mines: Field Observations and Numerical Model Assessment
- Investigation of Pillar-Roof Contact Failure in Northern Appalachian Stone Mine Workings
- Pillar Design
- Pillar Stability Issues Based on a Survey of Pillar Performance in Underground Limestone Mines
- Pillar Strength and Design Methodology for Stone Mines
- Preventing Injuries Caused by Unrecognized Stone Mine Roof Beam Failures With a Pro-Active Roof Control Plan
- Roof Span Design for Underground Stone Mines
- Roof Stability Issues in Underground Limestone Mines in the United States
- Content source: National Institute for Occupational Safety and Health, Mining Program