PSI - Issue 57

ScienceDirect Structural Integrity Procedia 00 (2022) 000 – 000 Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia

Procedia Structural Integrity 57 (2024) 428–436

© 2024 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 scientific committee of the Fatigue Design 2023 organizers © 2023 The Authors. Published by ELSEVIER B.V. 20 This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) 21 Peer-review under responsibility of the scientific committee of the Fatigue Design 2023 organizers 22 Keywords: Probabilistic fatigue modelling, Welded joints, Weld quality 23 24 The local weld joint geometry is a highly influencing factor for the fatigue strength of weld toe fatigue failures. 25 The stochastic nature of the welding process and its configurations are part of the uncertainty that drives the variation 26 in the local geometry, with local stress raising effect at the weld toe due to sharp transitions or unfavourable undercuts. 27 A deeper understanding of how the variation in the local weld geometry drives fatigue failure would make it possible 28 to optimise welding processes to achieve better fatigue strength beyond the discreet quality levels in current quality 29 standards. 30 Fatigue Design 2023 (FatDes 2023) 1 Effect of measured local weld geometry and its variability on the 2 local weld stress 3 Gustav Hultgren a* , Zuheir Barsoum a 4 a KTH Royal Institute of Technology, Department of Engineering Mechanics 5 Teknikringen 8, 100 44 Stockholm, Sweden 6 7 The local weld geometry and its variability can significantly affect the fatigue strength of structures, especially for 8 non-load-carrying welds. Standardised definitions, such as sharp transition radii or undercuts, govern stress-raising 9 effects at the weld toe. High-resolution digital tools can nowadays accurately determine these parameters, allowing 10 for studying the impact of geometry variability on fatigue strength. However, real welds rarely exhibit idealised 11 transitions as multiple radii, undercuts, and ripple lines introduce uncertainty in geometry estimations. Numerical 12 simulations of the actual weld geometry, with all its variations, in combination with probabilistic evaluations, have 13 shown great potential for studying the influence of competing notches in the weld. This study compares probabilistic 14 evaluations of 3D scanned welds with analytical relations for stress concentration factors. Results reveal no clear trend 15 between the analytical expressions and the ratio of simulated sectional stress to nominal stress. This highlights the 16 challenge of directly applying existing analytical equations to idealised measurement data from real welds in their as- 17 welded condition for fatigue strength estimations. Abstract 18 19 1. Introduction

* Corresponding author. Tel.: +46-70-190 97 92 E-mail address: gustavhu@kth.se

2452-3216 © 2024 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 scientific committee of the Fatigue Design 2023 organizers 10.1016/j.prostr.2024.03.046 2452-3216 © 2023 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 scientific committee of the Fatigue Design 2023 organizers