The Forgotten Denominator, Pillar Loading

Details

• Personal Author:
  Heasley, Keith A.
• Description:
  In the last few decades, a considerable amount of effort was directed at accurately determining the coal/pillar strength to use for safety designing coal mines. The outcome of this early work was the well known Obert-Duvall, Holland-Gaddy, Bieniawski, and Salamon-Munro equations for coal pillar strength. All of these equations were developed for, and were calibrated with, pillars in a large room-and-pillar area such that the loading could be determined using the "tributary-area" theory. In order to account for the abutment loads associated with full-extraction mining, the empirical methods have typically adopted a simple conceptualization of the abutment load through the use of an "abutment angle." Short of a complete numerical or analytical analysis of the coal seam and surrounding strata, very little work has been directed toward refining the empirical analysis of pillar loading. It appears that the vast majority of the research has been directed at determining the pillar strength, the numerator of the safety factor equation, when the denominator of the safety factor equation, the pillar loading, plays an equally important role in pillar design. This paper will address the deficit of pillar loading research by exploring the accuracy of the empirical abutment load calculations using insight provided by an elastic overburden model, a laminated overburden model and field observations. Ultimately, it is determined that a constant abutment angle probably over-predicts the abutment load as the mining depth increases. [Description provided by NIOSH]
• Subjects:
  Dust Engineering Environmental Pollution Lung Diseases Minerals Mining Occupational Exposure Occupational Health Respiratory System Respiratory Tract Diseases Safety Silicon Dioxide Workplace

  More +
• Keywords:
  Coal-mining Geology Mining-industry Rock-mechanics Room-and-pillar-mining Underground-mining
• Series:
  Mining Publications
• ISBN:
  9789058091550
• Publisher:
  A.A. Balkema
• Document Type:
  Text
• Genre:
  Proceedings
• Place as Subject:
  OSHA Region 1 ; OSHA Region 10 ; OSHA Region 3 ; Pennsylvania ; Vermont ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PRL - Pittsburgh Research Laboratory
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  457-464
• NIOSHTIC Number:
  nn:20023676
• Citation:
  Pacific rocks 2000: rock around the rim. Proceedings of the Fourth North American Rock Mechanics Symposium, NARMS 2000, July 31-August 3, 2000, Seattle, Washington. Girard JM, Leibman M, Breeds C, Doe T, eds. Brookfield, VT: A.A. Balkema, 2000 Jul; :457-464
• Editor(s):
  Girard JM; Leibman M; Breeds C; Doe T
• Federal Fiscal Year:
  2000
• Peer Reviewed:
  False
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:39ae67eaee2d928f7e81e092c2f64ff23ede95e55090fcff00e33115f4989d43ad3652663fa22d5287f80571664c250e53b9cec7d8efae550e03afc739b2dbd8
• Download URL:
  https://stacks.cdc.gov/view/cdc/220718/cdc_220718_DS1.pdf
• File Type:
  [PDF - 993.60 KB ]