PSI - Issue 68

ScienceDirect Structural Integrity Procedia 00 (2025) 000–000 Structural Integrity Procedia 00 (2025) 000–000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 68 (2025) 146–152

European Conference on Fracture 2024 Delamination analysis of a fixed-ended multilayered beam under twisted support Victor Rizov* Department of Technical Mechanics, University of Architecture, Civil Engineering and Geodesy, 1 Chr. Smirnensky blvd., 1046 – Sofia, Bulgaria Abstract This paper studies peculiarities of the delamination behaviour of a fixed-ended multilayered load-caring beam structure under twisted support. The layers of the beam are of different materials and have different thickness. Besides, the layers are inhomogeneous along the beam length. The cross-section of the beam is a rectangle. Both ends of the beam under consideration are fixed, i.e. the beam represents statically undetermined structure. No external loading is applied on the beam. However, the left-hand support of the beam is twisted. This induces stresses and strains in the statically undetermined beam which leads to delamination that is subject of analysis in the present paper. The strain energy release rate for the delamination is derived. For this purpose, the strain energy in the beam generated by the twisted support is determined and then differentiated with respect to the delamination area. The compliance of the beam under twisted support is analyzed to perform a verification of the solution of the strain energy release rate. A parametric investigation is carried-out in order to clarify the effects of a variety of factors like magnitude of the angle of support twist, beam geometry, configuration of layers, distribution of properties of layers along the beam length, etc. on delamination behaviour. © 2025 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 ECF24 organizers Keywords: Multilayered structure; delamintion; twisted support; fixed-ended beam; inhomogenity 1. Introduction Multilayered materials find wide application in many engineering structures, mechanisms and devices. The importance of these materials for the up-to-date engineering is confirmed also by the fact that many scientists have turned their attention to different aspects of the mechanical behaviour of multilayered structural components European Conference on Fracture 2024 Delamination analysis of a fixed-ended multilayered beam under twisted support Victor Rizov* Department of Technical Mechanics, University of Architecture, Civil Engineering and Geodesy, 1 Chr. Smirnensky blvd., 1046 – Sofia, Bulgaria Abstract This paper studies peculiarities of the delamination behaviour of a fixed-ended multilayered load-caring beam structure under twisted support. The layers of the beam are of different materials and have different thickness. Besides, the layers are inhomogeneous along the beam length. The cross-section of the beam is a rectangle. Both ends of the beam under consideration are fixed, i.e. the beam represents statically undetermined structure. No external loading is applied on the beam. However, the left-hand support of the beam is twisted. This induces stresses and strains in the statically undetermined beam which leads to delamination that is subject of analysis in the present paper. The strain energy release rate for the delamination is derived. For this purpose, the strain energy in the beam generated by the twisted support is determined and then differentiated with respect to the delamination area. The compliance of the beam under twisted support is analyzed to perform a verification of the solution of the strain energy release rate. A parametric investigation is carried-out in order to clarify the effects of a variety of factors like magnitude of the angle of support twist, beam geometry, configuration of layers, distribution of properties of layers along the beam length, etc. on delamination behaviour. © 2025 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 ECF24 organizers Keywords: Multilayered structure; delamintion; twisted support; fixed-ended beam; inhomogenity 1. Introduction Multilayered materials find wide application in many engineering structures, mechanisms and devices. The importance of these materials for the up-to-date engineering is confirmed also by the fact that many scientists have turned their attention to different aspects of the mechanical behaviour of multilayered structural components © 2025 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 ECF24 organizers

* Corresponding author. Tel.: (+399-2) 063 52 45/664; fax: (+359-) 86 56 863. E-mail address: v_rizov_fhe@uacg.bg * Corresponding author. Tel.: (+399-2) 063 52 45/664; fax: (+359-) 86 56 863. E-mail address: v_rizov_fhe@uacg.bg

2452-3216 © 2025 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 ECF24 organizers 2452-3216 © 2025 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 ECF24 organizers

2452-3216 © 2025 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 ECF24 organizers 10.1016/j.prostr.2025.06.035