Erosion

Erosion

Author: William Fred Adler

Publisher: ASTM International

Published: 1979

Total Pages: 668

ISBN-13: 9780803103344

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Rockburst Evolutionary Process and Energy Dissipation Characteristics

Rockburst Evolutionary Process and Energy Dissipation Characteristics

Author: Dazhao Song

Publisher: Springer

Published: 2019-04-27

Total Pages: 257

ISBN-13: 9811362793

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This book investigates the evolution process of rockburst based on the energy dissipation theory and proposes appropriate active prevention and control technologies. It discusses the electromagnetic radiation (EMR) generated by coal rock fractures as a measurement of the amount of dissipated energy, and the use of EMR to experimentally observe the time domain characteristics of energy dissipation during coal rock failure processes. It then proposes the concept of the rockburst activity domain system (RADS), establishes a dynamic pressure model of rockburst, and describes the energy criterion for rockburst instability. Lastly, it presents two waterjet cutting-based cases of pressure relief and rockburst prevention. The book serves as a reference resource for mine safety workers, engineering technicians, scientists, graduate students and undergraduates engaged in research on dynamic hazards such as rockburst..


Water-jet-assisted Cutting

Water-jet-assisted Cutting

Author:

Publisher:

Published: 1985

Total Pages: 96

ISBN-13:

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Greater mining productivity requires a more efficient cutting process. The cutting force available from today?s mining machines has been optimized with respect to machine size and weight. Researchers have shown that when employing water-jet-assisted cutting, bit forces and drum torques can be reduced significantly, which may allow mining machines to become lighter and more efficient. The Bureau of Mines has initiated a program to develop a water- jet-assisted rotary cutting system using the conventional bit assisted by a directed water jet operating at moderate pressures (3,000 to 10,000 psi). This water-jet-assisted cutting system has the potential to improve cutting efficiency without increasing machine horsepower or water usage (beyond what is presently used for dust control) or requiring fundamental changes in mining practice. IR addition to improvements in productivity, other anticipated benefits of water-jet cutting include reduced generation of respirable dust, elimination of frictional ignitions, increased bit life, reduced fines, and fewer machine vibrations. The papers presented at this open industry meeting discuss the development of water-jet-assisted cutting technology and future application of this technology to a variety of mining techniques including roof drilling and longwall mining.