Cemented Paste Backfill Geomechanics at the Lucky Friday Mine

Details

• Personal Author:
  Abraham H ; Board M ; Raffaldi MJ ; Seymour, Joseph B. ; Zahl, Eric G.
• Description:
  Underhand cut-and-fill mining has allowed for safe extraction of ore in many mines operating in weak rock or highly stressed, rockburst prone ground conditions. However, design of safe backfill undercuts poses unique geotechnical challenges that must be addressed by these operations. Hecla Mining Company and the Spokane Mining Research Division of the National Institute for Occupational Safety and Health have worked collaboratively for several years to better understand the geomechanics of cemented paste backfill (CPB) and thereby improve safety in underhand stopes. This work has included a series of laboratory strength studies and an extensive in situ backfill instrumentation program to monitor long term stope closure and resulting stress in the backfill. The fill must be strong enough to resist flexural failures, but the large stope closures (5 to 10 cm) that occur during undercutting also require the fill to have significant residual strength in order to remain stable after the elastic strain limit has been exceeded. This paper provides an overview of underhand-cut-and-fill mining with CPB as practiced at the Lucky Friday Mine, the collaborative research that has been undertaken with emphasis on the instrumentation and monitoring program, and technical insight that has been gained through this work. [Description provided by NIOSH]
• Subjects:
  Occupational Health Safety
• Keywords:
  Cements Failure Analysis Geologic Structures Geotechnical Engineering Ground Monitoring Horizontal Stress Rock Bursts Rock Mechanics Sensors Stope Mining Structural Analysis

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• Series:
  Mining Publications
• Publisher:
  American Rock Mechanics Association (ARMA)
• Document Type:
  Text
• Genre:
  Proceedings
• Place as Subject:
  Idaho ; OSHA Region 10 ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  SMRD - Spokane Mining Research Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• NIOSHTIC Number:
  nn:20053001
• Citation:
  52nd US Rock Mechanics/Geomechanics Symposium, June 17-20, 2018, Seattle, Washington. Alexandria, VA: American Rock Mechanics Association (ARMA), 2018 Jun; :ARMA 18-815
• Contact Point Address:
  M.J. Raffaldi, National Institute for Occupational Safety and Health, Spokane, WA, USA
• Federal Fiscal Year:
  2018
• NORA Priority Area:
  Mining
• Peer Reviewed:
  False
• Source Full Name:
  52nd US Rock Mechanics/Geomechanics Symposium, June 17-20, 2018, Seattle, Washington
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:0e4f8976072b4eca326ca9526b71a3b7c0f15ba991d542b53a3392d9fcf6f5a8f3aec05f7e650a10e3cba7d247494e4efcde88f4ed4374b412063017b43ed42a
• Download URL:
  https://stacks.cdc.gov/view/cdc/227722/cdc_227722_DS1.pdf
• File Type:
  [PDF - 1.60 MB ]