Stress Redistribution in a Longwall Yield Pillar – a Comparison Between Active Seismic Tomography and Theory [2022-08]

Details

• Personal Author:
  Coons DJ ; McCarter MK ; Pariseau, W. G. ; Wempen JM ; Westman EC
• Description:
  Safe, efficient underground mining is dependent upon proper pillar sizing. Pillar sizing is typically based on a combination of observation of prior behavior, point measurements, theory and numerical modeling. The actual stress redistribution within a pillar, while assumed for many years, has rarely been imaged. Such imaging can help confirm whether or not theoretical and numerical modeling methods agree with actual conditions within a pillar. This research presents a case study from a longwall mine in the western United States. A two-entry, gate-road yield pillar in the headgate of the mine was instrumented with seismometers and convergence monitoring stations, and was monitored over a period of about six months as the longwall face approached the pillar. In this paper, the stress distribution imaged using seismic tomography is compared to the stress distribution expected from theoretical models, geotechnical measurements and numerical models. The tomography results generally agree with those proposed by theory, convergence measurements and numerical modeling results. The agreement of the methods provides validation for the theorized stress redistribution, and this study provides further evidence that tomography can indicate the redistribution of induced stress within a mined rockmass and is another tool available to ensure that mining is conducted safely and efficiently. [Description provided by NIOSH]
• Subjects:
  Coal Mining Occupational Health Safety
• Keywords:
  Author Keywords: Longwall Mining Ground Control Longwall Mining Models Pillar Mechanics Room And Pillar Mining Seismic Tomography Underground Mines
• ISSN:
  0026-5187
• Document Type:
  Text
• Funding:
  Contract
• Genre:
  Abstract or Summary
• Place as Subject:
  OSHA Region 3 ; OSHA Region 8 ; Utah ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  48-50
• Volume:
  74
• Issue:
  8
• NIOSHTIC Number:
  nn:20066050
• Citation:
  Min Eng 2022 Aug; 74(8):48-50
• Email:
  ewestman@vt.edu
• Federal Fiscal Year:
  2022
• Performing Organization:
  University of Utah
• Peer Reviewed:
  True
• Source Full Name:
  Mining Engineering
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:ce5a7366ff11d38ec1649659775a24bb8b46b14ffc220b16ab311f8e6bad3a88394e01a3c78b9a14a1bac3028d64736cd6e27247db314a8a65a0051d5c029d60
• Download URL:
  https://stacks.cdc.gov/view/cdc/209131/cdc_209131_DS1.pdf
• File Type:
  [PDF - 274.52 KB ]