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Predicting impact damage of composite stiffened panels

Published online by Cambridge University Press:  04 July 2016

G. A. O. Davies
Affiliation:
Department of Aeronautics, Imperial College, London, UK
X. Zhang
Affiliation:
College of Aeronautics, Cranfield University, Bedford, UK

Abstract

This paper addresses the problem of the complex nature of low velocity impact damage in fabricated structures made of laminated carbon-epoxy composites. The structures chosen are stiffened compression panels since these are the most vulnerable to delamination and debonding. Four ‘top-hat’ stiffened panels were tested and predicted using a dynamic finite element code. The panels all had considerable postbuckling strength so the impact sites were carefully chosen to inflict maximum loss of strength. It was shown that the threshold energy for onset of delamination can be predicted using a dynamic finite element code. The amount of delamination or debonding is also predicted using a crude strength-based criterion, which seems to work only because the maximum impact force is a transient phenomenon of short duration.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2000 

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