Results 1 - 9 of 9

• Geophysical Methods to Detect Stress in Underground Mines
  3/1/2004 - Reports of Investigations
  Highly stressed rock in stopes continues to be a primary safety risk for miners in underground mines because this condition can result in failures of ground that lead to both injuries and death.
• Field Test with Strain-Gauged Friction Bolts at the Gold Hunter Mine, Mullan, Idaho, USA
  8/1/2003 - Conference papers
  To measure the loading behavior of friction bolts, NIOSH researchers installed strain gauges on the interior of friction bolts and developed a miniature data acquisition system (MIDAS) that fits inside the hollow portion of the friction bolt.
• 60 Years of Rockbursting in the Coeur D'Alene District of Northern Idaho, USA: Lessons Learned and Remaining Issues
  2/1/2002 - Conference papers
  Sixty years of rockbursting in the Coeur d'Alene district has taught painful lessons and led to practical advances in controlling rockburst hazards. This paper summarizes those lessons, concentrating on practical measures to reduce hazards.
• Geomechanics of Reinforced Cemented Backfill in an Underhand Stope at the Lucky Friday Mine, Mullan, Idaho
  7/1/2001 - Reports of Investigations
  Because backfill has occasionally collapsed into an active working area, posing a hazard to miners, engineers installed instruments in a cemented, backfilled, stope-ramp intersection at Hecla's Lucky Friday Mine.
• New Tricks for an Old Elephant: Revising Concepts of Coeur d'Alene Geology
  1/1/1998 - Peer reviewed journal articles
  The Coeur d'Alene Mining District of northern Idaho is remarkable for its number of large ore bodies and for the amount of its historical production of lead, zinc and silver. Since veins were first discovered in 1884, more than 127 Mt (140 million st) o...
• Investigation of a Rock-Burst Site, Sunshine Mine, Kellogg, Idaho
  1/1/1997 - Conference papers
  Rock masses in deep-level mines are subject to high stresses, which can result in unexpected failure of rock into mined-out openings. Personnel from two research centers of the former U.S. Bureau of Mines, Spokane and Twin Cities, investigated a rock b...
• In Situ Stress at the Lucky Friday Mine (In Four Parts): 3. Reanalysis of Overcore Measurements from the Star Mine
  7/1/1995 - Reports of Investigations
  U.S. Bureau of Mines researchers reviewed an in situ stress estimate developed from measurements of overcore strain taken at test sites on the 7300 and 7500 levels of the Star Mine near Mullan, ID. Although the field measurements of overcoring strain we...
• In Situ Stress at the Lucky Friday Mine (In Four Parts): 4. Characterization of Mine In Situ Stress Field
  7/1/1995 - Reports of Investigations
  Researchers at the U.S. Bureau of Mines collected and analyzed overcore measurements and other indicators of in situ stress characteristics at the Lucky Friday Mine, Mullan, ID. An analysis of these data revealed that significant local variations in in ...
• In Situ Stress at the Lucky Friday Mine (In Four Parts): 2. Analysis of Overcore Measurement From 5300 Level
  7/1/1995 - Reports of Investigations
  The U.S. Bureau of Mines conducted an overcore stress measurement on the 5300 level of the Lucky Friday Mine, Mullan, ID, to investigate the stress regime around an experimental stope in a rock-burst-prone mine. The result indicated a stress field with ...