SOME EXPERIMENTS ON SHELLING CRACKS IN RAILROAD RAIL (NO. 1) TWO DIMENSIONAL PHOTOELASTIC EXPERIMENTS ON A MODEL HAVING A FINE EDGE CRACK UNDER CONTACT LOAD

The shelling cracks grown in the head of rails are said to be fatigue cracks which are produced by excessive rolling pressure of wheels passing over them. The detailed mechanism of failure, however, has not yet been made clear. To find whether the growth of cracks be due to repeated shearing stress or mainly to repeated tensile stress is necesary both for clarifying the mechanism of shelling and for selecting the rail material. Two dimensional photoelastic investigations were carried out on half planes having a fine edge crack to which a contact load was applied and the fringe patterns at the end of the cracks were observed. When a semicircular model is pressed to a model which has an edge crack inclined at an angel of 30 degree to the contact surface, there grows a tangential force along the fracture surface when the contact load comes above the crack. When the contact load has an inclination toward the crack the tangential force along the fracture surface has a tendency to increase. When a semicircular model is pressed vertically to a model which has a vertical edge crack and the contact load comes adjacent to one side of the crack, there acts the largest tangential force along the fracture surface and the shearing stresses concentrate at the end of the crack, but the tensile stress does not appear. It is supposed from the above facts that the direction of a shelling crack in rail developing under contact loading will be affected by the shearing stresses solely or at least predominantly.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/3127232
• Corporate Authors:

  JAPANESE NATIONAL RAILWAYS

  TOKYO,   Japan 
• Authors:
  • Enomoto, N
  • TANAKA, N
• Publication Date: 1962-9

Media Info

• Features: Figures; References;
• Pagination: p. 34-37
• Serial:
  • Railway Technical Research Institute, Quarterly Reports
  • Volume: 3 N3
  • Publisher: Railway Technical Research Institute/Tetsudo Gijutsu Kenkyujo
  • ISSN: 0033-9008
  • Serial URL: http://www.rtri.or.jp/eng/

Subject/Index Terms

• TRT Terms: Defects; Photoelasticity; Railroad rails; Shear properties; Shelling (Metals); Stresses; Technology; Tension
• Uncontrolled Terms: Contact stress; Tensile stress
• Geographic Terms: Japan
• Old TRIS Terms: Photoelastic analysis; Rail stress; Shelling; Shelling (Rails)
• Subject Areas: Materials; Railroads;

Filing Info

• Accession Number: 00039983
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 8 1994 12:00AM