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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ScienceDirect

Procedia Structural Integrity 41 (2022) 103–114

2nd Mediterranean Conference on Fracture and Structural Integrity Viscoelastic inhomogeneous beam subjected to mechanical loading and periodically varying temperature: a longitudinal fracture analysis

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 This paper deals with analysis of longitudinal fracture of inhomogeneous beam structure that exhibits viscoelastic behaviour under mechanical loading and periodically varying temperature. The analysis is performed assuming that a longitudinal crack is located arbitrarily along the beam thickness. The mechanical loading representing a bending moment applied at the free end of the upper crack arm varies continuously with time. A solution of the strain energy release rate that takes into account the viscoelastic behaviour of the beam is derived. When deriving the solution, the viscoelastic behaviour and the varying tempera ture are treated by applying a time-dependent modulus that is obtained by using the constitutive law of a viscoelastic model having three components (a spring and two dashpots) under smoothly varying stress with time. The material properties of the viscoelastic model which are involved in the expression for the time-dependent modulus vary continuously along the length and thickness of the beam due to material inhomogeneity. The solution of the strain energy release rate is verified by analyzing the strain energy in the beam structure. The effects of the varying temperature, the loading conditions and the inhomogeneity on the strain energy release rate are investigated. © 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: Inhomogeneous beam structure; Viscoelastic behavior; Longitudinal fracture; Temperature; Mechanical loading This

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

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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. i li

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.2022.05.013