Report of Investigations 9040: Direct Measurement of Longwall Strata Behavior: A Case Study

Details

• Journal Article:
  Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 9040
• Personal Author:
  Hill, John L. III ; Listak, Jeffrey M. ; Zelanko, Joseph C.
• Description:
  The Bureau of Mines has conducted a rock mechanics study to monitor deformation of near-seam strata above a longwall panel in the Pittsburgh coalbed. The primary goal was to determine the height of caving immediately behind advancing longwall face supports. This study, although site specific, provides information on the caving mechanism associated with longwall extractions so that strata behavior and its interaction with longwall face supports can be better understood. Two holes were drilled, approximately 550 ft apart along the centerline of a longwall panel, from the surface to the coalbed approximately 650 ft below. Various downhole geotechnical instruments were used to monitor strata deformation. In addition, surface elevation surveys were conducted to differentiate between surface and subsurface activity. This report discusses the caving characteristics of the strata as the longwall panel approached and passed beneath the boreholes. Physical property data are also presented to demonstrate the relationship between caving behavior and local geology. Data show that immediate caving of strata above the longwall face occurred at a height less than 23.5 Ft and that strata behavior above longwall extractions is highly dependent upon lithology, with major disturbances occurring at weak lithologic zones. [Description provided by NIOSH]
• Subjects:
  Mining Occupational Health Safety
• Keywords:
  Strata; Longwall-mining; Mining-research; Lithology; Rock-mechanics; Mineral-industries
• Source:
  Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 9040, 1986 Jan; :1-19
• Series:
  NIOSH Numbered Publications   ; Mining Publications  
• Subseries:
  Report of Investigations
• Document Type:
  Text
• Genre:
  Report
• Place as Subject:
  OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  PRC - Pittsburgh Research Center
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  24 pdf pages
• NIOSHTIC Number:
  nn:10005313
• NTIS Accession Number:
  PB87-167466
• Federal Fiscal Year:
  1986
• Peer Reviewed:
  False
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:e538b63f550e45ba545c83cb439fd36cb0fd4eeba7ee8a2ea2c97f067ecfd2075cf75c641d3e52a8d7f8fb2b04aba383a9315665cfc85f24a4cb2c47b6df37d2
• Download URL:
  https://stacks.cdc.gov/view/cdc/10415/cdc_10415_DS1.pdf
• File Type:
  [PDF - 9.22 MB ]