PSI - Issue 41

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2022) 000 – 000

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Procedia Structural Integrity 41 (2022) 115–124

2nd Mediterranean Conference on Fracture and Structural Integrity Statically undetermined multilayered beam of non-linear viscoelastic behaviour: a delamination study

Victor Rizov* Department of Technical Mechanics, University of Architecture, Civil Engineering and Geodesy, 1 Chr. Smirnensky blvd., 1046 – Sofia, Bulgaria

© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the MedFract2Guest Editors. Abstract Delamination of a twice statically undetermined multilayered beam structure which has non-linear viscoelastic behaviour is studied analytically. The beam is made of layers whose time-dependent behaviour is treated by a non-linear viscoelastic mechanical model having equal number of springs and dashpots. The strain energy release rate is derived by analyzing the balance of the energy. The curvatures and the coordinates of neutral axes of the beam portions needed for obtaining of the strain energy release rate are found by resolving the static indeterminacy. The delamination is studied also by the method of J -integral to verify the strain energy release rate. In order to evaluate the effect of the static indeterminacy, an analysis of the strain energy release rate is carried-out also assuming that the beam under consideration is statically determinate structure. © 2022 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the MedFract2Guest Editors. Keywords: Time-dependent behaviour; Multilayered beam; Non-linear viscoelastic material; Statically undetermined structure; Delamination 1. Introduction Multilayered structural materials have been widely used in various applications in modern engineering. These materials represent systems of layers of different material properties and thicknesses. The concept of multilayered materials provides a mean of developing of highly efficient mechanical systems with excellent functional and structural performance in many engineering applications (Finot and Suresh (1996), Freund (1995), Kim et al. This is an open access article under th (htt n

* Corresponding author. Tel.: + (359-2) 963 52 45 / 664; fax: + (359-2) 86 56 863 E-mail address: v_rizov_fhe@uacg.bg

2452-3216 © 2022 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license ( https://creativecommons.org/licenses/by-nc-nd/4.0 ) Peer-review under responsibility of the MedFract2Guest Editors.

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the MedFract2Guest Editors. 10.1016/j.prostr.2022.05.014