Accession Number : ADA294648

Title :   Life Prediction Methodology for Composite Laminates. Part 2. Spectrum Fatigue.

Descriptive Note : Interim rept. 15 Jan 93-30 Dec 94,

Corporate Author : WRIGHT LAB WRIGHT-PATTERSON AFB OH

Personal Author(s) : Schaff, Jeffery R. ; Davidson, Barry D.

PDF Url : ADA294648

Report Date : DEC 1994

Pagination or Media Count : 36

Abstract : A previously developed model for predicting the life of composite structures under constant amplitude and two-stress level fatigue loadings is extended and applied to structures subjected to randomly-ordered loading spectra. The model is phenomenological and a limited amount of experimental data is required for its characterization. For uniaxially loaded laminates, this consists of static tension and compression strength distributions, S-N curves based on constant amplitude fatigue life distributions for two-to-three stress ratios, and a limited amount of two-stress level fatigue test results. The model is verified by comparing predicted fatigue life distributions to experimentally observed fatigue life data for a variety of laminates and load spectrums. Good correlation between theory and experiment is obtained for all loadings and laminates studied. (MM)

Descriptors :   *COMPOSITE MATERIALS, *LAMINATES, *FATIGUE(MECHANICS), LOAD DISTRIBUTION, LIFE EXPECTANCY(SERVICE LIFE), FATIGUE LIFE, STRESS ANALYSIS, COMPOSITE STRUCTURES, STRENGTH(MECHANICS), SPECTRA, TENSION, AMPLITUDE, COMPRESSIVE STRENGTH, COMPRESSIVE PROPERTIES.

Subject Categories : Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE