Roof Collapse Modeling with FLAC3D

Details

• Personal Author:
  Esterhuizen, Gabriel S. ; Tulu IB
• Description:
  Recently, a numerical model based approach for support analysis has been developed at the National Institute for Occupational Safety and Health (NIOSH). In this approach calibrated models are used to determine a stability factor for a supported entry. The stability factor is determined using the strength reduction method (SRM). The success of the SRM depends on the ability to accurately identify a collapsing or stable roof condition in the models. A collapse condition can be identified by considering the mechanical ratio and the velocity/acceleration of the roof grid points. It is found that during collapse, grid points of the zones within the collapsing roof move at least 50 to 100 times faster than in the remainder of the model. However, the default local damping scheme in FLAC3D attempts to arrest the collapsing roof, which may result in an incorrect assessment of roof stability. In order to solve this problem, combined damping is used. In addition, unloading of the model to simulate the excavation is controlled strictly with a relaxation algorithm to provide efficient energy dissipation. [Description provided by NIOSH]
• Subjects:
  Coal Coal Mining Communication Disaster Planning Electrical Equipment And Supplies Emergencies Mining Occupational Health Safety
• Keywords:
  Acceleration Analytical-processes Coal-mining Coal Mines Environmental-control Environmental-stress Environmental Monitoring Excavations Geology Ground-control Ground-stability Ground Monitoring Kinetics Longwall Mining Mathematical Models Mining-industry Rock-mechanics Roof Falls Roofing Roof Supports Roof Support Systems Strata Control Structural-analysis Underground-mining

  More +
• Series:
  Mining Publications
• ISBN:
  9781510828025
• Publisher:
  American Rock Mechanics Association (ARMA)
• Document Type:
  Text
• Genre:
  Proceedings
• Place as Subject:
  OSHA Region 3 ; OSHA Region 6 ; Pennsylvania ; Texas
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PMRD - Pittsburgh Mining Research Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  2
• NIOSHTIC Number:
  nn:20049287
• Citation:
  50th US Rock Mechanics/Geomechanics Symposium, June 26-29, 2016, Houston, Texas. Alexandria, VA: American Rock Mechanics Association (ARMA), 2016 Jun; 2:1391-1395
• Federal Fiscal Year:
  2016
• Peer Reviewed:
  False
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:e80535e6534fbb49fade1b7b359631cc2e04aeedaa5c7cdc7c81a4bff92582ec7d5447f872ff66f4b56dd7d4d3451bdab13d2914142c23e9e6e4b2d85354671a
• Download URL:
  https://stacks.cdc.gov/view/cdc/228365/cdc_228365_DS1.pdf
• File Type:
  [PDF - 143.47 KB ]