PSI - Issue 51

S.A. Elahi et al. / Procedia Structural Integrity 51 (2023) 30–36 S.A. Elahi et al./ Structural Integrity Procedia 00 (2022) 000–000

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required to have a propagating crack emanating from the pit bottom. The pit shape is assumed to be semi-elliptical and the pit dimensions (pit depth and pit width) serve as input parameters to the model. Consequently, to be able to estimate the fatigue strength degradation over time, the corrosion pit configuration evolution is assessed using field data reported in the literature. According to the simulation results for 7.5 years of exposure of S355 steel to the North Sea environment, the normalized fatigue strength degradation rate is predicted to be almost 0.27 per year in the first year which decreases to around 0.02 per year in the last year. Acknowledgements W. De Waele would like to acknowledge the financial support of the Belgian Federal Government through the Energy Transition Fund (ETF). N. Larrosa would like to acknowledge the funding provided by the UK Engineering and Physical Sciences Research Council under grant no. EP/S012362/1. References Anandavijayan, S., Mehmanparast, A., Braithwaite, J., Brennan, F., Chahardehi, A., 2021. Material pre-straining effects on fatigue behaviour of S355 structural steel. Journal of Constructional Steel Research, 183, 106707. Balbín, J. A., Chaves, V., Larrosa, N. O., 2021. Pit to crack transition and corrosion fatigue lifetime reduction estimations by means of a short crack microstructural model. Corrosion Science, 180(December 2020), 109171. Blekkenhorst, F., Ferrari, G. M., Van Der Wekken, C. J., Ijsseling, F. P., 1986. Development of high strength low alloy steels for marine applications : Part 1 : Results of long term exposure tests on commercially available and experimental steels. Biritish Corrosion Journal, 21(3), 163–176. Borko, K., Hadzima, B., Pastorek, F., 2018. The Corrosion Properties of S355J2 Steel Welded Joint in Chlorides Environment. Periodica Polytechnica Transportation Engineering, 47(4), 342–347. Chaves, V., Navarro, A., 2009. Application of a microstructural model for predicting notch fatigue limits under mode I loading. International Journal of Fatigue, 31(5), 943–951. Christ, H. J., Fritzen, C. P., Köster, P., 2014. Micromechanical modeling of short fatigue cracks. Current Opinion in Solid State and Materials Science, 18(4), 205–211. Dzioba, I., Lipiec, S., 2016. Microstructure , strength properties and fracture toughness of S355JR steel. AIP Conference Proceedings, 1780, 0500(2016). Fatoba, O., Akid, R., 2022. On the behaviour of small fatigue cracks emanating from corrosion pits: Part I – The influence of mechanical factors. Theoretical and Applied Fracture Mechanics, 117(July 2021), 103154. Hansson, P., Melin, S., Persson, C., 2008. Computationally efficient modelling of short fatigue crack growth using dislocation formulations. 75, 3189–3205. Haute, C. Vanden, Thibaux, P., 2022. Quantification of pitting and stress concentration factors on steel coupons exposed to seawater in the north sea. Proceedings of the ASME 2022, 41st International Conference on Ocean, Offshore and Arctic Engineering OMAE2022, 1–7. Hills, D. A., Kelly, P. A., Dai, D. N., Korsunsky, A. M., 1996. Solution of Crack Problems: The Distributed Dislocation Technique. Springer Science+Business Media, B.V. Kitagawa, H., Takahashi, S., 1976. Applicability of fracture mechanics to very small cracks or cracks in the early stage. Proceeding of the Second International Conference on Mechanical Behavior of Materials, 627–631. Lehto, P., Romanoff, J., Remes, H., Sarikka, T., 2016. Characterisation of local grain size variation of welded structural steel. Weld World, 60, 673–688. Navarro, A., De los Rios, E. R., 1988a. An alternative model of the blocking of dislocations at grain boundaries. Philosophical Magazine A, 57(1), 37–42. Navarro, A., De los Rios, E. R., 1988b. Short and long fatigue crack growth: A unified model. Philosophical Magazine A, 57(1), 15–36. Navarro, A., De los Rios, E. R., 1992. Fatigue Crack Growth Modelling by Successive Blocking of Dislocations. Mathematical and Physical Sciences, 375–390. Vallellano, C., Navarro, A., Domínguez, J., 2000. Fatigue crack growth threshold conditions at notches. Part I : theory. Fatigue & Fracture of Engineering Materials & Structures, 23(2), 113–121.