PSI - Issue 82

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2026) 000–000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 82 (2026) 239–245

© 2026 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 ICSID organizers Abstract This paper concerns the modelling of lightweight composite sandwich pipes consisting of fibre-reinforced inner and outer skins with homogeneous or graded-density core under combined mechanical and thermal loads. A finite element model capable of thermomechanical stress analysis is developed and validated against the three-dimensional elasticity solution. As an example analysis, stress states are determined for pipes comprising carbon/epoxy skins with homogeneous epoxy, homogeneous polyvinyl chloride (PVC) or graded PVC core under loads relevant to offshore piping applications. A graded core is shown to offer a compromise in terms of pipe weight and stresses in the fibre layers. © 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. 8th International Conference on Structural Integrity and Durability (ICSID2025) Modelling of composite sandwich pipe subjected to combined mechanical and thermal loading Igor Guz a, *, James Hastie b , Maria Kashtalyan b a Heriot-Watt University, School of Engineering & Physical Sciences, Edinburgh, Scotland, U.K. b University of Aberdeen, School of Engineering, Centre for Micro- and Nanomechanics (CEMINACS), Aberdeen, Scotland, U.K..

Keywords: Composite pipe modelling; thermoelastic analysis; functionally graded material

1. Introduction Fibre-reinforced plastic (FRP) sandwich pipes, consisting of inner and outer filament-wound (FW) skins bonded to a polymeric core, are an attractive alternative to traditional metallic pipes for high specific strengths and stiffnesses, superior thermal insulation and enhanced corrosion resistance. When in operation, oil and gas pipelines are exposed to surface pressures in combination with thermal loads that may include large through-thickness thermal

* Corresponding author. Tel.: +0131 4513474. E-mail address: i.guz@hw.ac.uk

2452-3216 © 2026 The Authors. Copy from the contract: 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 ICSID organizers

2452-3216 © 2026 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 ICSID organizers 10.1016/j.prostr.2026.04.037