Results 131 - 140 of 348

• A First Step in Developing Roof Support Design Criteria Based on Ground Reaction Data for Pittsburgh Seam Longwall Tailgate Support
  7/1/2008 - Conference papers
  In this NIOSH study to optimize standing roof support design, ground response curves were developed for longwall tailgate conditions from numerical models of Pittsburgh Coal Seam geology.
• Catastrophic Failures of Underground Evaporite Mines
  7/1/2008 - Conference papers
  This paper examines catastrophic failures of evaporite mines (including salt, potash and trona) that show that violent failure does, in fact, occur and attempts to identify common factors and characterize the mechanism of failure.
• Field Observations and Numerical Studies of Horizontal Stress Effects on Roof Stability in U.S. Limestone Mines
  6/1/2008 - Peer reviewed journal articles
  This paper describes a modeling approach that can be used as a tool to evaluate potential roof failure and optimize the stability of room and pillar layouts.
• Comparison of the Transverse Load Capacities of Various Block Ventilation Stoppings under Arch Loading Conditions
  6/1/2008 - Conference papers
  This paper compares the transverse load capabilities of several block materials and wall dimensions commonly used in stopping constructions based upon simulated three-hinge, rigid-arch loading tests of half-wall constructions.
• Guidelines for Permitting, Construction, and Monitoring of Retention Bulkheads in Underground Coal Mines
  6/1/2008 - Information Circulars, Safety guidelines, tips, and checklists
  The guidelines in this report are to be used as a tool to identify areas or conditions that could impact the long-term stability of an underground fluid retention system and to give direction in addressing these situations.
• Three-Dimensional Time-Lapse Velocity Tomography of an Underground Longwall Panel
  6/1/2008 - Peer reviewed journal articles
  This paper describes the 3D velocity tomograms that were generated to image the stress redistribution around an underground coal longwall panel to produce a better understanding of the mechanisms that lead to ground failure, especially rockbursts.
• Improving the Performance of Fan-Powered Dust Collectors in Stone-Cutting Applications
  6/1/2008 - Conference papers
  The objective of the research was to cost-effectively increase the air cleaning volume and improve dust capture efficiency of an off-the-shelf dust collector with a larger motor and blower.
• Rock Mass Behavior and Support Response in a Longwall Panel Pre-Driven Recovery Room
  3/1/2008 - Conference papers
  Some surprising results were revealed in this study designed and implemented by NIOSH to evaluate the effectiveness of pre-driven longwall recovery rooms supported with pumpable concrete roof supports.
• Using Mine Planning and Other Techniques to Improve Ventilation in Large-Opening Mines
  2/1/2008 - Conference papers
  This paper describes NIOSH research demonstrating that the ventilation of large-opening mines improves significantly by including ventilation requirements in the mine planning process and implementing some practical techniques during mining.
• Methods for Determining Roof Fall Risk in Underground Mines
  11/1/2007 - Peer reviewed journal articles
  This paper discusses a method to determine the roof fall risk using a qualitative risk analysis technique.