PSI - Issue 75

Martin Edgren et al. / Procedia Structural Integrity 75 (2025) 555–563 Martin Edgren et Al. / Structural Integrity Procedia (2025)

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• The investigated notched prefatigued HFMI treated specimens show significant improvement regarding life extension. Three out of four specimens went to run-out and the fourth specimen showed a fatigue life well above the IIW proposed S-N curve for HFMI treated specimen of detail No 525. • Furthermore, the weld quality varied across the short weld length and varied between the specimens. However, the HFMI treatment was successful for all four specimens indicating the robustness of the treatment method being successful for varying weld qualities, in some cases even below the recommended B90 according to IIW. Acknowledgements The authors would like to acknowledge the partners of the LifeExt2 Implementation project (Prolonging the Life of Existing Steel Bridges) and express their gratitude to the funding agency, VINNOVA (Grant Number 2021-01045). 8. Declaration P. Shams-Hakimi, F. Carlsson, M. Al-Emrani, and H. Al- Karawi, ‘Assessment of in -service stresses in steel bridges for high- frequency mechanical impact applications’, Eng Struct , vol. 241, p. 112498, Aug. 2021, doi: 10.1016/J.ENGSTRUCT.2021.112498. [2] H. Al- Karawi, ‘Corrosion Effect on the Efficiency of High -Frequency Mechanical Impact Treatment in Enhancing Fatigue Strength of Welded Steel Structures’, J Mater Eng Perform , vol. 31, no. 11, pp. 9151 – 9158, Nov. 2022, doi: 10.1007/s11665-022-06918-x. [3] R. Aldén, Z. Barsoum, T. Vouristo, and M. Al- Emrani, ‘Robustness of the HFMI techniques and the effect of weld quality on the fatigue life improvement of welded joints’, Welding in the World , vol. 64, no. 11, pp. 1947 – 1956, Nov. 2020, doi: 10.1007/s40194-020-00974-4. [4] ‘ISO 5817:2023 - Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) — Quality levels for imperfections’. Accessed: Apr. 15, 2025. [Online]. Available: https://www.iso.org/standard/80209.html [5] Marquis G.B. and Barsoum Z., IIW Recommendations on high frequency mechanical impact (HFMI) treatment for improving the fatigue strength of welded joints, ISBN 978-981-10-2504-4 . Springer, 2016. [6] Edgren M., Barsoum Z., Åkerlind K., and Al- Emrani M., ‘Evaluation of HFMI as a Life Extension Technique for Welded Bridge Details’, Procedia Structural Integrity , vol. 19, pp. 73 – 80, 2019. [7] Y. Banno, K. Kinoshita, and Z. Barsoum, ‘Numerical investigation of crack opening -closing behavior on pre- fatigued welded joints repaired by HFMI’, Welding in the World , vol. 66, no. 4, pp. 767 – 781,Apr. 2022, doi: 10.1007/s40194-022-01263-y. [8] Y. Banno, K. Kinoshita, and Z. Barsoum, ‘Life extension analysis considering crack opening -closing behavior in HFMI- treated welds’, Welding in the World , vol. 68, no. 2, pp. 333 – 345, Feb. 2024, doi: 10.1007/s40194-023-01583-7. [9] M. Leitner, S. Gerstbrein, M. J. Ottersböck, and M. Stoschka, ‘Fatigue Strength of HFMI -treated High strength Steel Joints under Constant and Variable Amplitude Block Loading’, Procedia Eng , vol. 101, no. C, pp. 251 – 258, Jan. 2015, doi: 10.1016/J.PROENG.2015.02.036. [10] P. J. Haagensen and S. J. Maddox, IIW Recommendations On Methods for Improving the Fatigue Strength of Welded Joints: IIW-2142-110 . Elsevier Ltd, 2013. Accessed: Apr. 15, 2025. [Online]. Available: http://www.sciencedirect.com:5070/book/9781782420644/iiw-recommendations-on-methods-for improving-the-fatigue-strength-of-welded-joints [11] H. Al-Karawi, R. U. F. von Bock und Polach, and M. Al- Emrani, ‘Fatigue crack repair in welded structures via tungsten inert gas remelting and high frequency mechanical impact’, J Constr Steel Res , vol. 172, Sep. 2020, doi: 10.1016/j.jcsr.2020.106200. [12] G. B. Marquis, Z. Barsoum, and M. Leitner, ‘New developments and guideline updates for HFMI treatment Conflict of interest. The author declares no competing interests. 9. References [1]