Durability Methods Development. Volume 4. Initial Quality Representation

Abstract

The initial fatigue quality of the durability critical parts of an aircraft structure is one of the key input parameters for the durability analysis to be performed in the present investigation. We considered that either the EIFS (Equivalent Initial Flaw Size) or TTCI (Time-To-Crack-Initiation) represents such an initial quality that controls the durability of aircraft. A statistical characterization of the EIFS data is attempted by fitting various probability distribution functions thereto. The EIFS data considered consist of three samples of size 37, 37 and 38. These data sets are examined to see if they fit; (a) the distributions of the Johnson family including the log-normal distribution; (b) the Weibull distribution; (c) the distributions of the Pearson family; (d) the asymptotic distributions of largest values; and (e) the TTCI compatible distributions. It is found that, with respect to the data examined, the Weibull compatible, log-normal compatible, and second asymptotic distributions provide the best fit.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1979
Accession Number
ADA114263

Entities

People

  • M. Shinozuka

Organizations

  • General Dynamics

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Force
  • Air Force Facilities
  • Aircrafts
  • Crack Propagation
  • Cracks
  • Data Analysis
  • Data Sets
  • Distribution Functions
  • Dynamics
  • Goodness Of Fit Tests
  • Normal Distribution
  • Probability Distribution Functions
  • Probability Distributions
  • Random Variables
  • Standards
  • Statistical Analysis
  • United States

Fields of Study

  • Mathematics

Readers

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