Estimation of failure load of adhesively bonded composite joints with embedded crack in adherends: bond EM

Estimation of failure load of adhesively bonded composite joints with embedded crack in adherends: bond EM

James Polagangu, Byji Varughese

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Abstract. The authors developed Bond Energy Method (Bond EM), a novel quasi-numerical-analytical failure estimation method based on the energy conservation principle. This method previously estimated the ultimate failure load of adhesively bonded composite (ABC) repaired joints of third-party experiments without crack. In this present study, authors used the same method to estimate the ultimate failure load of third-party ABC joint test specimens with an embedded crack in the adherends. The adhesive layer and adherends are modeled using one and two-dimensional finite elements in such a way that one plus two is three to capture three-dimensional stresses. The crack in adherend is modeled by adding a Teflon layer of 0.02 mm between its composite stacking sequence. Static stress analysis is carried out to obtain the precise force and stress values in the adhesive layer and adherends per unit load (1000 N). These values are appropriately substituted in mathematical equations of Bond EM and estimated the ultimate failure load of L. Tong’s test specimens. The difference in mathematical estimation is found in the range of (+4.29, +18.15)% for higher side estimation; (-4.80, -34.50)% for lower side estimation. The study compared the estimated failure load by Bond EM with that of other popular third-party methods, and Bond EM is found superior to all other methods considered in this study.

Keywords
Composite Structures, Failure Load, Bonded Joints, Delamination, Crack, Bond Energy Method

Published online 8/10/2023, 12 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: James Polagangu, Byji Varughese, Estimation of failure load of adhesively bonded composite joints with embedded crack in adherends: bond EM, Materials Research Proceedings, Vol. 31, pp 324-335, 2023

DOI: https://doi.org/10.21741/9781644902592-34

The article was published as article 34 of the book Advanced Topics in Mechanics of Materials, Structures and Construction

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

References
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