THE EFFECT OF PERIODIC-RANDOM LOADING ON FATIGUE CRACK GROWTH

A theory of fatigue crack growth based on the concept of damage accumulation is presented which takes some account of the effect of periodic-random loading. The Dugdale model of plasticity is used to calculate the distribution of the energy dissipated during stress cycling in the plastic zones of a crack embedded in a material sample of infinite extent. The author shows how to calculate the damage accumulated by decomposing the random group of stress levels into significant complete stress cycles of various amplitudes. A simple short numerical algorithm is presented which performs this decomposition. A crack-growth law is derived having a very simple form which automatically incorporates the condition for catastrophic failure.

• Corporate Authors:

  National Physical Laboratory, England

  Queens Road
  Teddington, Middlesex,   England 
• Authors:
  • McCartney, L N
• Publication Date: 1975-7-8

Media Info

• Features: Appendices; Figures; References;
• Pagination: 31 p.

Subject/Index Terms

• TRT Terms: Algorithms; Cracking; Deformation curve; Fatigue cracking; Steel; Stochastic processes; Structural analysis
• Uncontrolled Terms: Fatigue analysis
• Subject Areas: Data and Information Technology; Railroads;

Filing Info

• Accession Number: 00172927
• Record Type: Publication
• Report/Paper Numbers: N B-630 Prepub Rpt
• Files: TRIS
• Created Date: Mar 29 1978 12:00AM