J.W. Cardinal, D.H. Wieland, M.F. Kanninen

To evaluate and extend the remaining life of aging aircraft fatigue critical areas (FCLs) subject to variable amplitude loadings, fracture mechanics models are routinely utilized to perform fatigue crack growth calculations. These calculations, commonly referred to as durability and damage tolerance analyses (DADTA), require a large amount of input data encompassing the characterization of the spectrum; the development of a fracture mechanics model to compute the applied stress intensity factor as a function of crack length; the strength and fracture properties of the material; the fatigue crack growth properties of the material; and the assumptions used to model the geometry and material properties. The modeling approaches used, along with their inherent engineering judgements, can only be validated using laboratory coupon spectrum fatigue tests and full-scale durability and damage tolerance tests. This poster presentation will focus on unique aspects of recent DADTA correlations with test results for typical aging aircraft FCLs performed at SwRI. Predictions of crack growth models and the determination of crack growth retardation parameters were validated against coupon spectrum test results and crack growth measurements made during full-scale damage tolerance tests. These include cracks growing out of and towards coldworked holes, shorter than expected crack propagation lives for a crack growing from the edge of an attachment lug towards the lug hole, correlations (and differences) between full-scale and laboratory coupon test results, determination of continuing damage sites, and fracture mechanics modeling issues for unique FCL geometries. Lessons learned at SwRI regarding the correlation of fracture mechanics analysis and testing will be summarized.

5th International Conference on Structural Airworthiness of New and Aging Aircraft, Hamburg, 1993

Conference Abstract

englisch

21,0 x 29,7 cm, 2 Seiten

DGLR-Bericht, 1993, 1993-02, 5th International Conference on Structural Airworthiness of New and Aging Aircraft - Proceedings; S.219-220; 1993; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

structural fatigue

Bestellbar

1993