A SUGGESTED EXPLANATION FOR THE ANGLE OF LATERAL BREAKOUT WITH PENCIL POINT PICKS

The mode of action of pencil-point picks has long been a matter of debate, and has seemed less tractable to simple theoretical analysis than that of wedge-shaped picks. The breakage pattern produced by pencil-point picks cutting in rock has been observed experimentally. An explanation is given in terms of tensile failure in the rock. A theory is proposed which predicts accurately the characteristic angles of the broken material. The theory encourages the view that a common basis exists for the explanation of the action of both pencil-point and wedge-shaped picks. (Author/TRRL)

• Corporate Authors:

  Mining Research and Development Establishment

  Ashby Road, Stanhope Bretby
  Burton-on-Trent,   England 
• Authors:
  • Evans, I
  • HURT, K G
• Publication Date: 1979-9

Media Info

• Features: Figures; Photos; References;
• Pagination: 7 p.
• Serial:
  • MRDE Laboratory Note
  • Publisher: Mining Research and Development Establishment

Subject/Index Terms

• TRT Terms: Angularity; Failure; Forecasting; Fracture mechanics; Mathematical models; Rock excavation; Rocks; Tensile strength; Tension; Tools
• Uncontrolled Terms: Angles; Breaking up
• Old TRIS Terms: Angles (Geometry)
• ITRD Terms: 6427: Angle; 3604: Breaking up; 3674: Equipment; 5520: Failure; 132: Forecast; 6473: Mathematical model; 4154: Rock; 5502: Tension
• Subject Areas: Construction; Geotechnology; Highways; I50: Construction and Supervision of Construction;

Filing Info

• Accession Number: 00324333
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Report/Paper Numbers: Monograph
• Files: ITRD, TRIS
• Created Date: Sep 16 1981 12:00AM