PSI - Issue 68

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

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 68 (2025) 272–278

European Conference on Fracture 2024 The Effect of Alternating Wet-Dry Conditions in the Fatigue Life of S355G10+M Steel under Corrosion-Fatigue Testing M. Álvarez a, *, A. Vergara a , M. Escalero a , M. Olave a a Mechanical Reliability Department (Mechatronic Area), Ikerlan Technology Research Center, J.M. Arizmendiarrieta Ibilbidea 2, 20500 Arrasate-Mondragón, Spain Abstract In addition to corrosion, offshore wind turbines are subjected to a spectrum of structural loads that lead to dynamic stresses that increase corrosion pit growth kinetics. Alternation of wet and dry stages is a very important factor to be considered, due to significant pitting corrosion rate increment. In this work, the effect of wet-dry conditions in the remaining life of structural steel S355G10+M was investigated. Combined corrosion-fatigue tests were performed in samples of S355G10+M steel with an artificially generated corrosion pit, under simulated wet-dry conditions at different axial load levels. Experimental results were compared with existing fatigue data in air of S355 steels and design curves for free corrosion in seawater. Additionally, these results were contrasted with S-N curves for corrosive environment obtained from theoretical models available in the literature. This approach enabled the evaluation of fatigue life from a phenomenological perspective. © 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) © 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

Peer-review under responsibility of ECF24 organizers Keywords: corrosion-fatigue; pitting; wet-dry; S355 steel; offshore

1. Introduction Corrosion-fatigue (CF) represents a very aggressive and complex failure mechanism in offshore structures, turning monopile foundation into a life-limiting component for an offshore wind turbine (OWT). Although corrosion protection methods are implemented in the external surface of offshore monopiles exposed to the tidal zone, they have

* Corresponding author. Tel.: +34 943 712400 E-mail address: maalvarez@ikerlan.es

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.2025.06.053