Results 81 - 90 of 99

• Technology News 448 - Improving the Performance of Longwall Gob Gas Ventholes
  3/1/1995 - Technology News
  The absence of fundamental scientific and engineering principles in the design and placement of gob gas ventholes can cause difficulties for mine operators when gas emissions increase because of a change in mine design or because variable geologic condi...
• Modeling the Effects of Longwall Mining on the Ground Water System
  1/1/1995 - Reports of Investigations
  A hydrologic-subsidence investigation was performed to evaluate the effects of longwall mining on the local groundwater regime through field monitoring and numerical modeling.
• Timing and Duration of Subsidence Due to Longwall Mining
  1/1/1995 - Reports of Investigations
  Subsidence data gathered by the U.S. Bureau of Mines over a series of longwall panels in the Pittsburgh Coalbed were studied to obtain insight as to the role of time in the subsidence process. These results were then compared to data from three other si...
• Technology News 430 - Translucent Face Partition Reduces Longwall Worker's Dust Exposure
  3/1/1994 - Technology News
  The USBM's current approach to air splitting consists of using a polyester mesh partition to overcome the visibility problems of a solid barrier.
• Longwall Retreat of Gate Road Pillars
  1/1/1993 - Reports of Investigations
  This report investigates the removal of gate road chain pillars in conjunction with longwall retreat mining. The objective was to determine how the pillars, supplemental support, and entries were affected by the longwall abutment pressure.
• Behavior of Simulated Longwall Gob Material
  1/1/1993 - Reports of Investigations
  This report presents results of a U.S. Bureau of Mines study of longwall gob material. The objective of this work was to determine material stiffness properties of the gob for use in numerical models or rock mass response to longwall mining.
• Analysis and Design Considerations for Superimposed Longwall Gate Roads
  1/1/1992 - Information Circulars
  A U.S. Bureau of Mines investigation of longwall panel layouts to maximize coal recovery and minimize interactive problems in multiple-seam operations.
• Rock Mechanics Investigations at the Lucky Friday Mine (In Three Parts): 1. Instrumentation of an Experimental Underhand Longwall Stope
  1/1/1992 - Reports of Investigations
  Researchers monitored rock mass response to mining of an experimental underhand longwall stope in Hecla Mining Company's Lucky Friday Mine, Mullan, Idaho. This is part 1 of 3.
• Relationship of Coal Seam Parameters and Airborne Respirable Dust at Longwalls
  1/1/1992 - Reports of Investigations
  The U.S. Bureau of Mines investigated the relationship of bituminous coal seam parameters and the amount of respirable dust generated at longwalls.
• Examination of Design and Operation Practices for Longwall Shields
  1/1/1992 - Information Circulars
  This report examines shield design, operation practices, and the consequences for using high-capacity shield support systems. An optimization goal is to minimize support loading by using an active shield setting force compatible with strata behavior.