Roof Wedge Stability: A Simple Analytical Model and Numerical Validation Using Deformable Blocks

Details

• Personal Author:
  MacLaughlin, Mary M.
• Description:
  Wedge-shaped roof falls are an extremely common mode of failure of underground openings in jointed rock. Although a number of sophisticated analytical solutions have been developed to determine the stability of roof wedges, a simple approach may also be used to provide an estimate of wedge stability. The simple two-dimensional model assumes the wedge is symmetric in shape and the resultant force on the sides of the wedge is horizontal. It may be used to determine stability of a wedge given dip angles of the joints forming the sides of the wedge and the friction angle, assumed to be the same on both surfaces. It may also be used to calculate the friction angle for stability given the dip angles of the joint sets. Numerical analyses previously conducted using the distinct element Inethod (Itasca's UDEC software) show excellent agreement with the simple analytical solution, for one specific set of conditions and a limited sensitivity analysis with rigid blocks. The results of a more in-depth sensitivity analysis with deformable blocks, presented here, show that the numerical results are quite insensitive to substantial variations in the Young's modulus and Poisson's ratio of the rock, orientation and stiffness of the joints, and ill situ stresses. [Description provided by NIOSH]
• Subjects:
  Chemistry Coal Hazardous Substances Hazardous Waste Mining Occupational Health Safety
• Keywords:
  Analytical-chemistry Analytical-models Analytical-processes Coal-mining Coal-processing Computer-models Computer-software Ground-control Ground-stability Longwall-mining Mine-shafts Mining-industry Models Room-and-pillar-mining Underground-mining

  More +
• Series:
  Mining Publications
• ISBN:
  0772767084
• Publisher:
  University of Toronto Press
• Document Type:
  Text
• Genre:
  Proceedings
• Place as Subject:
  Montana ; OSHA Region 10 ; OSHA Region 8 ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  SRL - Spokane Research Laboratory
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  1
• NIOSHTIC Number:
  nn:20030552
• Citation:
  NARMS-TAC 2002, "Mining and Tunnelling Innovation and Opportunity," Proceedings of the 5th American Rock Mechanics Symposium and the 17th Tunnelling Association of Canada Conference, July 7-10, 2002, Toronto, Ontario, Canada. Hammah R, Bawden W, Curran J, Telesnicki M, eds., Toronto, Ontario, Canada: University of Toronto Press, 2002 Jul; 1:663-669
• Editor(s):
  Hammah R; Bawden W; Curran J; Telesnicki M
• Federal Fiscal Year:
  2002
• Peer Reviewed:
  False
• Source Full Name:
  NARMS-TAC 2002, "Mining and Tunnelling Innovation and Opportunity," Proceedings of the 5th American Rock Mechanics Symposium and the 17th Tunnelling Association of Canada Conference, July 7-10, 2002, Toronto, Ontario, Canada
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:fc1531d24410c320afbb1f6c57d41ad8706b97b3708c5d5b210147635571ceff7a50ff33ada17a6740ee7eca6ec5fe19efff3f9ccfc156c27e0aed9ad84fe5ee
• Download URL:
  https://stacks.cdc.gov/view/cdc/226594/cdc_226594_DS1.pdf
• File Type:
  [PDF - 2.90 MB ]