The Paton Welding Journal, 2025, №01

2025 №01 (02)

DOI of Article 10.37434/tpwj2025.01.03

2025 №01 (04)

---

The Paton Welding Journal, 2025, #1, 15-20 pages

Peculiarities of calculation of stress concentration factors in thin-sheet butt welded joints with the consideration of initial angular deformation

A.V. Moltasov, P.M. Tkach, M.M. Dyman, V.G. Kot, I.G. Tkach

E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine. E-mail: moltasov@gmail.com

Abstract
The paper is devoted to studying the influence of initial angular deformation caused by uneven transverse sagging of the butt weld during cooling on the stress concentration factors (SCF) in the transition zones from the face reinforcement and the weld root to the base metal (BM). An analysis of the existing formulas was carried out to determine the factor that considers the influence of initial angular deformation on the SCF on the fusion line of the weld with the BM. An analysis of the available formulas was carried out to determine the factor that takes into account the effect of initial angular deformation on the SCF on the fusion line of the weld with the BM. As a result, it was found that these formulas were developed for joints with a butt weld symmetrical relative to the median plane of the plates being welded and cannot be used for calculations near the weld root. A theoretical justification is given that initial angular deformation should lead to a decrease in stresses on the root side of the joint. New analytical formulas for the determination of the SCF on the fusion line of the weld root with the BM are proposed, considering initial angular deformation. A specific example was used to show that the presence of initial angular deformation really results in a decrease in stresses on the root side of the joint. The results of analytical calculations were confirmed by numerical calculations using the finite element method.
Keywords: butt welded joint, angular deformation, stress concentration, tension, bending, weld root

Received: 25.09.2024
Received in revised form: 22.10.2024
Accepted: 22.01.2025

References

1. Vershinsky, S.V., Vinokurov, V.A., Kurkin, S.A. et al. (1975) Design of welded structures in mechanical engineering. Ed. by S.A. Kurkin. Moscow, Mashinostroenie [in Russian].
2. Zhu, J., Barsoum, I., Barsoum, Z., Khurshid, M. (2022) Evaluation of local stress-based fatigue strength assessment methods for cover plates and T-joints subjected to axial and bending loading. Fatigue and Fracture of Engineering Materials and Structures, 9 (45), 2531-2548. https://doi.org/10.1111/ffe.13764
3. Remes, H., Romanoff, J., Lillemäe, I. et al. (2017) Factors affecting the fatigue strength of thin-plates in large structures. Inter. J. Fatigue, 101, 397-407. https://doi.org/10.1016/j.ijfatigue.2016.11.019
4. Trufiakov, V.I., Dvoretsky, V.I., Mikheev, P.P. et al. (1990) Strength of welded joints under variable loads. Ed. by V.I. Trufiakov. Kyiv, Naukova Dumka [in Russian].
5. Makarov, I.I. (1977) Method of calculating the coefficient of stress concentration in butt-welded joints. Welding Production, 4(24), 6-8.
6. Colchen, D. (1999) Actual effect of weld defects on the fatigue behavior of aluminium butt welds. Welding in the World, 6(43), 25-32.
7. Hobbacher, A.F. (2016) Recommendations for fatigue design of welded joints and components. 2nd Ed., Berlin, Springer. https://doi.org/10.1007/978-3-319-23757-2
8. Lillemäe, I., Lammi, H., Molter, L., Remes, H. (2012) Fatigue strength of welded butt joints in thin and slender specimens. Inter. J. Fatigue, 44, 98-106. https://doi.org/10.1016/j.ijfatigue.2012.05.009
9. Mancini, F., Remes, H., Romanoff, J., Reinaldo Gonc alves, B. (2020) Stress magnification factor for angular misalignment between plates with welding-induced curvature. Welding in the World, 4(64), 729-751. https://doi.org/10.1007/s40194-020-00866-7
10. Knysh, V.V., Klochkov, I.N., Pashulya, M.P., Motrunich, S.I. (2014) Increase of fatigue resistance of sheet welded joints of aluminum alloys using high-frequency peening. The Paton Welding J., 5, 21-27. https://doi.org/10.15407/tpwj2014.05.04
11. Knysh, V.V., Solovei, S.A. (2017) Improving the durability of welded joints with fatigue damage: Monography. Kyiv, Politekhnika [in Russian].
12. Lukianenko, A., Labur, T.M., Pokliatskyi, A.G. et al. (2019) Investigation of fatigue strength and norms of emission of harmful substances in the air during MIG and TIG welding of 1460 aluminum-lithium alloy. FME Transact., 3(47), 608-612. https://doi.org/10.5937/fmet1903608L
13. Motrunich, S., Klochkov, I., Pokliatsky, A. (2020) High cycle fatigue behaviour of thin sheet joints of aluminium-lithium alloys under constant and variable amplitude loading. Welding in the World, 12(64), 1971-1979. https://doi.org/10.1007/s40194-020-00976-2
14. Moltasov, A., Tkach, P., Ustynenko, O., Protasov, R. (2022) Effect of load eccentricity on stress condition of butt welded joint with asymmetrical reinforcement. Strojnicky Casopis, 1(72), 99-108. https://doi.org/10.2478/scjme-2022-0010
15. Goyal, R., El-Zein, M., Glinka, G. (2016) A robust stress analysis method for fatigue life prediction of welded structures. Welding in the World, 2(60), 299-314. https://doi.org/10.1007/s40194-016-0295-y
16. Moltasov, A.V. (2019) Stressed state of a butt-welded joint with regard for displacements of the centers of inertia. Mater. Sci., 3(55), 358-366. https://doi.org/10.1007/s11003-019-00310-2
17. Baumgartner, J., Bruder, T. (2013) An efficient meshing approach for the calculation of notch stresses. Welding in the World, 57(1), 137-145. https://doi.org/10.1007/s40194-012-0005-3
18. Molski, K.L., Tarasiuk, P. (2020) Stress concentration factors for butt-welded plates subjected to tensile, bending and shearing loads. Materials, 13(8), 1798. https://doi.org/10.3390/ma13081798

---

Suggested Citation

A.V. Moltasov, P.M. Tkach, M.M. Dyman, V.G. Kot, I.G. Tkach (2025) Peculiarities of calculation of stress concentration factors in thin-sheet butt welded joints with the consideration of initial angular deformation. The Paton Welding J., 01, 15-20.

---