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Failure behavior of composite laminates under four-point bending

Sonmez, Fazil O.; Koc, Murat; Sonmez, Fazil O; Ersoy, Nuri; Cinar, Kenan


Fazil O. Sonmez

Murat Koc

Fazil O Sonmez

Nuri Ersoy
Senior Lecturer in Mechanical Engineering

Kenan Cinar


In this study, failure behavior of fiber-reinforced composites under four-point bending is investigated. First, the tests are modeled analytically using the classical lamination theory (CLT). The maximum allowable moment resultants of [ 12]Toffaxis laminate as well as balanced and symmetric angle-ply [ 3/ 3]s composite laminates as a function of fiber orientation angle, , are obtained using Tsai-Wu, maximum stress, maximum strain, Hashin, Tsai-Hill, Hoffman, quadric surfaces, modified quadric surfaces, and Norris failure criteria. Second, the same tests are simulated using the finite element method (FEM). Thermal residual stresses are calculated and accounted for in the failure analysis. An analysis is conducted for optimal positioning of the supports so as to ensure that intralaminar failure modes dominate interlaminar (delamination) failure mode. A test setup is then constructed accordingly and experiments are conducted. The correlation of the predicted failure loads and the experimental results is discussed. The quadric surfaces criterion is found to correlate better with the experimental results among the chosen failure criteria for the selected configurations.


Koc, M., Sonmez, F. O., Ersoy, N., & Cinar, K. (2016). Failure behavior of composite laminates under four-point bending. Journal of Composite Materials, 50(26), 3679-3697.

Journal Article Type Article
Acceptance Date Jan 1, 2016
Online Publication Date Jan 6, 2016
Publication Date Nov 1, 2016
Journal Journal of Composite Materials
Print ISSN 0021-9983
Publisher SAGE Publications
Peer Reviewed Peer Reviewed
Volume 50
Issue 26
Pages 3679-3697
Keywords laminated composites, failure criteria, residual stresses, out-of-plane loading, four-point bending, classical lamination theory, finite element modeling
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Additional Information Additional Information : Copyright(c)2016 Reprinted by permission of SAGE publications.


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