Development of a Field Method to Evaluate Mechanical Properties of Roof Strata

Details

• Personal Author:
  Cotten SA ; Farrand JA ; Giraldo LB ; Hill JL
• Description:
  During conventional drilling in underground mining, several variables including thrust, rotational velocity, torque, and penetration rate must be simultaneously monitored in order to detect and interpret lithologic changes. This paper presents the development of a new approach to sense and characterize lithologic changes derived from the use of the Helical Drag Bit (HDB). Because of its particular geometry, the HDB can assess lithologic changes based only on measuring one drilling parameter. A theoretical relationship that correlates material unconfined compressive strength with the force of cutting is presented. Results of laboratory experiments in sedimentary rocks of various strengths confirm a torque-unconfined compressive strength relationship for the rock types drilled with the HDB. Recent underground tests have subsequently demonstrated that the geometry of the HDB can be optimized to obtain repeatable results. This method has the potential to quickly and simply detect and interpret lithologic changes within a borehole. Preliminary results indicate that a log of rock strength is possible. [Description provided by NIOSH]
• Subjects:
  Coal Coal Mining Construction Industry Construction Materials Mining Occupational Health Safety
• Keywords:
  Coal Mining Construction Materials Ground Control Ground Stability Mine Shafts Mining Industry Rock Drillers Rock Mechanics Roof Support Systems Underground Mining
• ISBN:
  9781604234541
• Publisher:
  American Rock Mechanics Association (ARMA)
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Proceedings
• Place as Subject:
  OSHA Region 3 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-9
• NIOSHTIC Number:
  nn:20053064
• Citation:
  Alaska Rocks 2005, Proceedings of the 40th U.S. Rock Mechanics Symposium, Anchorage, Alaska, June 25-29, 2005. Alexandria, VA: American Rock Mechanics Association (ARMA), Paper No. ARMA/USRMS 05-795, 2005 Jun; :1-9
• Editor(s):
  Chen G; Huang S; Zhou W; Tinucci J
• Federal Fiscal Year:
  2005
• Performing Organization:
  Raytheon Utd, Inc.
• Peer Reviewed:
  False
• Start Date:
  20020930
• Source Full Name:
  Alaska Rocks 2005, Proceedings of the 40th U.S. Rock Mechanics Symposium, Anchorage, Alaska, June 25-29, 2005
• End Date:
  20060929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:bf0a6683d0cca587825c565dc761113c2971714ad0c756bc35afe7dcbf2c3fab78bc96e14b1ed7eb038cc1d7994fbc15df64ac94b6cd802a81764ed976919dc9
• Download URL:
  https://stacks.cdc.gov/view/cdc/215912/cdc_215912_DS1.pdf
• File Type:
  [PDF - 1.94 MB ]