Results 1 - 10 of 48

• Stability Mapping to Examine Ground Failure Risk: A Field Study at a Limestone Mine
  7/1/2009 - Conference papers
  This paper presents a description of geologic settings, mining conditions, rockmass characterization with geotechnical risk assessment, analysis, mapping, and control techniques used at an underground stone mine in Central Pennsylvania.
• Performance Characteristics for Welded Wire Screen Used for Surface Control in Underground Coal Mines
  2/1/2009 - Conference papers
  The load-deformation characteristics and the load capacity of welded wire screen (roof screen) used to control ground fall were evaluated in the laboratory in a specially built test frame.
• Development and Application of the Coal Mine Roof Rating (CMRR)
  5/1/2007 - Conference papers
  This paper discusses the sources used in developing the CMRR, describes the CMRR data collection and calculation procedures, and briefly presents a number of practical mining applications in which the CMRR has played a prominent role.
• Analysis of Roof Bolt Systems
  8/1/2001 - Conference papers
  A statistical study of roof bolt performance was conducted in 37 U.S. mines. Analysis of the results led to guidelines for making preliminary estimates for bolt length, capacity, and pattern to improve roof stability in difficult conditions.
• Mistakes, Misconceptions, and Key Points Regarding Secondary Roof Support Systems
  8/1/2001 - Conference papers
  This paper discusses misconceptions about how roof supports perform and factors that impact their performance. The paper is limited to a discussion of secondary roof support systems and powered roof supports such as longwall shields.
• Advance and Relieve Mining: A Method to Mitigate the Effects of High Horizontal Stress on the Mine Roof
  2/1/2001 - Conference papers
  Evaluation of the "Advance and Relieve" mining method is described to determine effectiveness for conditions where high horizontal stresses caused long running roof falls resulting in hazardous conditions and the premature abandonment of panels.
• Optimizing Secondary Roof Support with the NIOSH Support Technology Optimization Program (STOP)
  8/1/2000 - Conference papers
  The 1990s saw an unprecedented increase in technologies for more effective, easier to install roof support in underground mines. To facilitate application and improve mine safety, NIOSH developed the Support Technology Optimization Program (STOP).
• Report on Early Strength Performance of Modern Day Weak Rock Mass Shotcrete Mixes
  2/1/2010 - Conference papers
  NIOSH is investigating the use of shotcrete in weak rock mass mines with the objective of reducing fatalities and injuries resulting from rock fall accidents.
• Current Trends in Reducing Ground Fall Accidents in US Coal Mines
  2/1/2009 - Conference papers
  Each of the electronic versions of the MSHA fatality reports since 1995 was analyzed in detail, categorized by the type of the ground fall hazard. The remainder of the paper is devoted to evaluating each of the five largest categories.
• Dynamic Failure in Deep Coal: Recent Trends and a Path Forward
  7/1/2008 - Conference papers
  The centerpiece of this project is development of a Dynamic Failure Control Program to monitor evolution of dynamic failure hazards with changing geologic conditions to assure that control and protective measures are appropriately deployed.