Analysis of the Influence of Mechanical Couplings in Laminate Beams on the Adherence of the Assumed Boundary Conditions in the DCB Test Configuration

Analysis of the Influence of Mechanical Couplings in Laminate Beams on the Adherence of the Assumed Boundary Conditions in the DCB Test Configuration

Jakub Paśnik, Sylwester Samborski, Jakub Rzeczkowski, Katarzyna Słomka

Abstract. This paper shows numerical analyses of delamination in coupled laminates using finite element method. With increasingly wide spreading use of laminate composites a research development of those materials goes on. It is a common knowledge that the main form of damage in composites is delamination that is a loss of cohesion between neighboring layers. The main aim of the conducted research is to obtain the strain energy release rate (SERR) distributions along initial delamination front and verifying compliance of experimental and numerical analyses. Some analyses were performed using numerical models based on the double cantilever beam (DCB) test configuration, because it allowed to determine the values of SERR in mode I, GI. The analyses were carried out using the Abaqus/CAE finite element software environment. Models of the specimens to be tested experimentally were elaborated in accordance with the DCB test configuration for which the boundary conditions and the load were specified. To model delamination process in composite beams the virtual crack closure technique (VCCT) was used [1]. In addition, numerical analyses of the boundary conditions and the laminate stacking sequence effect on the SERR distribution were done [1]. What is more, experimental analyses of crack shape were carried out. The results were obtained for two kinds of coupled layups: bending – extension and bending – twisting, as well as for uncoupled specimens and were compared mutually: the coupled and the uncoupled layups. The results of tests showed significant influence of boundary conditions and laminate stacking sequence both on the GI distribution along delamination front and on the crack front shape. It was noted that couplings have considerable impact on both numerical analyses’ results and can induce unwanted deformations of the test specimens during physical experiments. Moreover, crack shapes in numerical models and in experimental specimens were compared.

Keywords
Composite Laminate, Finite Element, Delamination, Double – Cantilever Beam, VCCT

Published online 5/25/2019, 7 pages
Copyright © 2019 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Jakub Paśnik, Sylwester Samborski, Jakub Rzeczkowski, Katarzyna Słomka, Analysis of the Influence of Mechanical Couplings in Laminate Beams on the Adherence of the Assumed Boundary Conditions in the DCB Test Configuration, Materials Research Proceedings, Vol. 12, pp 45-51, 2019

DOI: https://doi.org/10.21741/9781644900215-6

The article was published as article 6 of the book Experimental Mechanics of Solids

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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