Results 31 - 40 of 52

• Multiple Seam Mining Interactions: Case Histories from the Harris No. 1 Mine
  8/1/2005 - Conference papers
  Results show that the remnant upper seam structure's size can influence multiple seam interaction. Specifically, smaller critically loaded upper seam pillars appear more likely to cause lower seam ground control problems than wider pillars.
• Investigation of Pillar-Roof Contact Failure in Northern Appalachian Stone Mine Workings
  8/1/2004 - Conference papers
  Underground limestone mine roofs in Northern Appalachia can be subject to high horizontal stresses. A case study is presented showing that induced stress changes in the immediate roof are less likely if the pillars contain weak bedding planes.
• Reducing the Risk of Ground Falls During Pillar Recovery
  12/1/2003 - Conference papers
  Pillar recovery has been associated with nearly one third of roof fall fatalities in underground coal mines during the past decade. This paper discusses design methods and technologies that have been transferred and implemented in mining.
• Deep Cover Pillar Extraction in the U.S. Coalfields
  8/1/2002 - Conference papers
  A study is described with the objective of evaluating the various methods and strategies by which panels, production pillars and barrier pillars are developed and extracted under deep cover, and to develop appropriate design guidelines.
• Evaluation of Pillar Recovery in Southern West Virginia
  8/1/2002 - Conference papers
  Studies have identified a number of factors for evaluating a pillar extraction plan. This paper discusses each of the factors, presents relevant accident statistics, and shows how the risk factors can be combined to estimate the overall hazard.
• Sizing of Final Stumps for Safer Pillar Extraction
  8/1/2001 - Conference papers
  The risk of major pillar falls can often be reduced by leaving final stumps, large enough to protect the intersection but small enough to not inhibit gob caving. Analyses were conducted to assess factors on the size variation of remnant stumps.
• The Forgotten Denominator: Pillar Loading
  8/1/2000 - Conference papers
  This paper addresses a deficit in pillar loading research by exploring the accuracy of empirical abutment load calculations using insight provided by an elastic overburden model, a laminated overburden model and field observations.
• Analysis of Pillar Design Practices and Techniques for U.S. Limestone Mines
  12/1/1999 - Peer reviewed journal articles
  As underground stone mining expands to deeper cover and more efficient methods are used, effective stone pillar design methods become more important. In this paper, 72 stone mine pillar designs are examined for factors affecting stability.
• Comparison of Seismic Tomography, Strain Relief, and Ultrasonic Velocity Measurements to Evaluate Stress in an Underground Pillar
  3/1/1999 - Conference papers
  An investigation of an underground pillar at a mine in Lead, SD. Using the results, researchers hypothesize that pillar rocks have the ability to withstand stress an order of magnitude greater than they currently sustain.
• Pillar Design Issues for Underground Stone Mines
  1/1/1999 - Conference papers
  This paper examines current design practices for stone mines and discusses issues for safe mine layouts so that a rational first approach towards balancing the demands for increased production can be weighed against increased risk to worker safety.