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Title: Functionally graded stitched laminates: illustration on the example of a double cantilever beam
Author (s): Birman, Victor
Byrd, Larry W.
Department/Lab Affiliations: Center for Infrastructure Engineering Studies
Engineering Education Center at St. Louis
Keywords: Beams
cantilevers
laminates
Issue Date: 2006
Publisher: American Society of Civil Engineers
Citation: Birman, V. and L.W. Byrd, “Functionally Graded Stitched Laminates: Illustration on the Example of a Double Cantilever Beam,” ASCE Journal of Aerospace Engineering, Vol. 19, 2006, pp. 217-226.
Abstract: Although stitched laminates have been shown effective in preventing delamination failure, the presence of stitches results in a degraded in-plane strength and stiffness in such structures. The solution suggested in the paper is based on using stitches only in a part of the structure where they serve as arrestors of delamination cracks, while the part subject to considerable in-plane loading could remain unstitched. This approach, that could be called "functionally graded stitching," is considered on the example of a double cantilever beam (DCB) with a preexisting delamination crack that has penetrated into the stitched region of the beam. As is shown in the paper, the distribution of stitches in a functionally graded DCB (and in any other laminated structure) should be chosen to prevent three major failure modes. These modes include the failure of the stitches, bending failure of the unstitched delaminated section of the structure, and continuous crack propagation through the stitched region. The results obtained in the paper for the static problem clearly illustrate the feasibility of using functionally graded stitched laminates retaining in-plane strength and stiffness, while providing barriers to delamination cracks in less loaded regions of the structure. Additionally, the approach to the solution of the dynamic problem presented in the paper may be applied to the analysis of fatigue delamination cracks in partially stitched structures.
Type: Article - Journal
text
In Title: Journal of Aerospace Engineering
Copyright Notice: This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.
Pre-print: archiving status unclear; Post-print: author can archive with restrictions;Restriction: 90 days after publication; Conditions: Publisher's version/PDF cannot be used;Internet site or institutional repository;Must link to publisher version at ASCE Civil Engineering Database(http://cedb.asce.org);Publisher copyright and source must be acknowledged;
FULL COPYRIGHT INFORMATION:
http://pubs.asce.org/authors/journal/Posting+Papers+on+the+Internet.htm
Publisher URL:
http://dx.doi.org/10.1061/(ASCE)0893-1321(2006)19:4(217)
Link to this page:
http://scholarsmine.mst.edu/post_prints/FunctionallyGradedStitchedLaminatesIllustration_09007dcc8057d66a.html



titleFunctionally graded stitched laminates: illustration on the example of a double cantilever beam
contributor.authorBirman, Victor
contributor.authorByrd, Larry W.
contributor.deptlabCenter for Infrastructure Engineering Studies
contributor.deptlabEngineering Education Center at St. Louis
contributor.sponsorAir Force Office of Scientific Research
subjectBeams
subjectcantilevers
subjectlaminates
date.issued2006
publisherAmerican Society of Civil Engineers
identifier.citationBirman, V. and L.W. Byrd, “Functionally Graded Stitched Laminates: Illustration on the Example of a Double Cantilever Beam,” ASCE Journal of Aerospace Engineering, Vol. 19, 2006, pp. 217-226.
identifier.pub.URI
http://dx.doi.org/10.1061/(ASCE)0893-1321(2006)19:4(217)
description.abstractAlthough stitched laminates have been shown effective in preventing delamination failure, the presence of stitches results in a degraded in-plane strength and stiffness in such structures. The solution suggested in the paper is based on using stitches only in a part of the structure where they serve as arrestors of delamination cracks, while the part subject to considerable in-plane loading could remain unstitched. This approach, that could be called "functionally graded stitching," is considered on the example of a double cantilever beam (DCB) with a preexisting delamination crack that has penetrated into the stitched region of the beam. As is shown in the paper, the distribution of stitches in a functionally graded DCB (and in any other laminated structure) should be chosen to prevent three major failure modes. These modes include the failure of the stitches, bending failure of the unstitched delaminated section of the structure, and continuous crack propagation through the stitched region. The results obtained in the paper for the static problem clearly illustrate the feasibility of using functionally graded stitched laminates retaining in-plane strength and stiffness, while providing barriers to delamination cracks in less loaded regions of the structure. Additionally, the approach to the solution of the dynamic problem presented in the paper may be applied to the analysis of fatigue delamination cracks in partially stitched structures.
typeArticle - Journal
type.DCMITypetext
type.statusPostprint
rightsThis material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.
rightsPre-print: archiving status unclear; Post-print: author can archive with restrictions;Restriction: 90 days after publication; Conditions: Publisher's version/PDF cannot be used;Internet site or institutional repository;Must link to publisher version at ASCE Civil Engineering Database(http://cedb.asce.org);Publisher copyright and source must be acknowledged;
rights.URI
http://pubs.asce.org/authors/journal/Posting+Papers+on+the+Internet.htm
relation.isPartOfJournal of Aerospace Engineering
date.available2008-10-01T18:34:05Z
identifier.persist.URI
http://scholarsmine.mst.edu/post_prints/FunctionallyGradedStitchedLaminatesIllustration_09007dcc8057d66a.html