Double-Linear Cumulative-Damage Reliability Method

Abstract

Fatigue reliability calculations during iterations of the design process have been demonstrated as practical using new analytical and numerical methods based on analytical cumulative-damage reliability tools (alpha-functions). Effects of fatigue strength and usage distribution may be studied in the presence of load variation. However, to date, the development of the alpha-functions has been centered on use of the Palmgren-Miner cycle-ratio summation rule for cumulative damage, also known as the Linear Damage Rule (LDR). This paper extends the alpha-function toolbox for use in determining reliability based on the Manson-Halford Double Linear Damage Rule (DLDR). Examples demonstrate use of the method and charts are provided to illustrate the sensitivity of the cumulative-damage reliability problem to load and strength variations. For a given reliability, probabilistic DLDR methods demonstrate significant reductions in life when compared to LDR methods. The importance of understanding and applying the appropriate LDR, DLDR, or other material characterization is apparent.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 2011
Accession Number
ADA545867

Entities

People

  • Robert E. Benton Jr.

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Abstracts
  • Amplitude
  • Army Aviation
  • Coefficients
  • Composite Materials
  • Engineering
  • Fatigue Life
  • Helicopters
  • Materials
  • Notation
  • Probability
  • Probability Density Functions
  • Random Variables
  • Sensitivity
  • Standards
  • Test And Evaluation
  • Virginia

Fields of Study

  • Engineering

Readers

  • Software Engineering.
  • Structural Health Monitoring of Composite Structures.