PSI - Issue 57

J. Berthellemy / Structural Integrity Procedia 00 (2023) 000 – 000 Available online at www.sciendirect.com

Available online at www.sciendirect.com $ ) $- /

Available online at www.sciencedirect.com $ ) $- / Structural Integrity Procedia 00 (2023) 000 – 000

www.elsevier.com/loc ate/procedia www.elsevier.com/loc ate/procedia

ScienceDirect

Procedia Structural Integrity 57 (2024) 872–903 Structural Integrity Procedia 00 (2023) 000 – 000

© 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 Finally, the effects of corrosion, in particular the case of the weathering steels when used in the transition zones will be discussed in detail using models using the “Effective Notch Stress Method” based on tests carried out on samples for the Academy of Sciences of the Czech Republic by Ludwig Kunz. Of course, the aging of weathering steels in case of birds droppings is not considered in this study. Even without birds droppings, the fatigue resistance of some weathering steels details has to be reduced considering the Clause 7.1(5) of the French National Annex to EC3 1-9 when compared to the categories given by the tables of the Eurocodes for painted details. Finally, the effects of corrosion, in particular the case of the weathering steels when used in the transition zones will be discussed in detail using models using the “Effective Notch Stress Method” based on tests carried out on samples for the Academy of Sciences of the Czech Republic by Ludwig Kunz. Of course, the aging of weathering steels in case of birds droppings is not considered in this study. Even without birds droppings, the fatigue resistance of some weathering steels details has to be reduced considering the Clause 7.1(5) of the French National Annex to EC3 1-9 when compared to the categories given by the tables of the Eurocodes for painted details. Keywords: bridges; fatigue, weathering steels; cope holes; transition zones. Fatigue Design 2023 (FatDes 2023) Considerations regarding the fatigue design of the steel bridges Jacques BERTHELLEMY 1 Steel Bridges Engineering Expert at Cerema, France Chairman of TC50 European Committee (Lighting columns) Abstract The fatigue damage of steel bridges is prone to occur under a large amount of heavy traffic and be a worldwide problem leading to serious disasters. This communication will discuss the importance of the correct evaluation of the fatigue category of resistance for the safety and durability of bridges. Although much attention is usually rightly paid by engineers to the effects of traffic, on the other hand the effect of stress concentrations which modify the category of detail of the tables of the Eurocode is still very poorly known. We will deal with multiple examples to illustrate the question: the replacement of the cylinder head of the François I bridge in Le Havre at the very beginning of the 80s is an excellent example of an approach to the calculation of stress concentration factors by finite elements, which made it possible to solve the fatigue problems of this movable bridge. On the other hand, the cracking of the bridges of Chamousset where a then forbidden constructive arrangement was nevertheless built shows that the question is not a view of the mind: If the problem had not been identified and the bridge put under annual surveillance for the hot spots concerned, the two bridges could have collapsed. Today, Clause 7.1(5) of the French National Annex to EC3 1-9 has put manufacturers under the obligation to take into account stress concentration factors since 2011. Several features will be reviewed, such as for example the thickness transition zones with and without cope hole, the anchorages of hangers, the studs under tension and bending, the bottom cuts of the vertical stiffeners that actually do not help regarding fatigue, and the interruptions of guide rails. Fatigue Design 2023 (FatDes 2023) Considerations regarding the fatigue design of the steel bridges Jacques BERTHELLEMY 1 Steel Bridges Engineering Expert at Cerema, France Chairman of TC50 European Committee (Lighting columns) Abstract The fatigue damage of steel bridges is prone to occur under a large amount of heavy traffic and be a worldwide problem leading to serious disasters. This communication will discuss the importance of the correct evaluation of the fatigue category of resistance for the safety and durability of bridges. Although much attention is usually rightly paid by engineers to the effects of traffic, on the other hand the effect of stress concentrations which modify the category of detail of the tables of the Eurocode is still very poorly known. We will deal with multiple examples to illustrate the question: the replacement of the cylinder head of the François I bridge in Le Havre at the very beginning of the 80s is an excellent example of an approach to the calculation of stress concentration factors by finite elements, which made it possible to solve the fatigue problems of this movable bridge. On the other hand, the cracking of the bridges of Chamousset where a then forbidden constructive arrangement was nevertheless built shows that the question is not a view of the mind: If the problem had not been identified and the bridge put under annual surveillance for the hot spots concerned, the two bridges could have collapsed. Today, Clause 7.1(5) of the French National Annex to EC3 1-9 has put manufacturers under the obligation to take into account stress concentration factors since 2011. Several features will be reviewed, such as for example the thickness transition zones with and without cope hole, the anchorages of hangers, the studs under tension and bending, the bottom cuts of the vertical stiffeners that actually do not help regarding fatigue, and the interruptions of guide rails.

Keywords: bridges; fatigue, weathering steels; cope holes; transition zones. 1-Contact: Jacques.Berthellemy@sfr.fr

1-Contact: Jacques.Berthellemy@sfr.fr

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.2024.03.093