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The Unpredictable Life Cycle of a Coal Pillar

Public Domain
File Language:
English


Details

  • Personal Author:
  • Corporate Authors:
    National Institute for Occupational Safety and Health. Pittsburgh Research Laboratory
  • Description:
    A unique circumstance created by monitoring a pre-driven longwall recovery room permitted measuring the stresses of a coal pillar throughout its entire life cycle in less than a week. A fender pillar, created in approximately the middle of a longwall panel at a depth of 650 ft, transformed from a solid barrier pillar - to a yielding pillar - to a residual pillar as 3 ft slices were methodically removed with the longwall shearer. The complete transformation, or life cycle, took place in less than 12 hours. The stresses were quickly transferred from the pillar onto the standing pumpable concrete supports and into the outby pillars. Roof to floor closure measurements, combined with the timing of the pillar behavior, provides a detailed look at the uncontrollable convergence of underground mine openings. Pillars remain the most important form of primary support and understanding these life cycles is vital for safe and efficient mine design, in both room and pillar and longwall panel extractions.
  • Subjects:
  • Source:
    Proceedings of the 26th International Conference on Ground Control in Mining, July 31 - August 2, 2007, Morgantown, West Virginia. Peng SS, Mark C, Finfinger GL, Tadolini SC, Khair AW, Heasley KA, Luo Y, eds., Morgantown, WV: West Virginia University, 2007 Jul; :90-96
  • Document Type:
    Text
  • Genre:
    Conference Publications
  • CIO:
    National Institute for Occupational Safety and Health (NIOSH)
  • NIOSHTIC Number:
    nn:20032433
  • Collection(s):
  • Main Document Checksum:
    urn:sha-512:c16970f8f2022cc03e9c346a990c4608a3761cfee2ebae2f8c650b2119e13afc8abd31e69eec27f6e08ef4c981a95bf6ce3fc9bee2914e425c7fb9212f135fff
  • Download URL:
  • File Type:
    Filetype[PDF - 1.14 MB ]
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