Overview
![](/assets/images/picto-drapeau-france-3a76576a5d60a512053b4612ab58dae5.png)
ABSTRACT
A structure is made up of constructive details: it can fail when at least one of the constructive details reaches one of the ultimate limit states.
One of these limit states is the fatigue limit state. This state reflects progressive cracking due to repeated loading over a very large number of cycles over time. Once a certain threshold of cracking has been reached, there is a risk of failure.
The use of different parts of Eurocode 1 for fatigue loads, and other parts of Eurocode 3 for the actual verification, makes the understanding of the verification process quite complex. The purpose of this article is therefore to gather all the information on this subject.
Read this article from a comprehensive knowledge base, updated and supplemented with articles reviewed by scientific committees.
Read the articleAUTHOR
-
Mladen LUKIĆ: Chairman of CECM TC6 "Fatigue and fracture" – Convenor of CEN/TC250/SC3 WG9 "EN 1993-1-9 - Research Project Manager CTICM (Saint-Aubin, France)
INTRODUCTION
Crack initiation necessarily starts from a defect. In the case of a smooth-appearing detail, the crack may originate from microscopic defects at the grain scale, or from edge defects due to flame cutting, drilling, etc., or it may originate from the surface.
In the case of structural details with welds, it's more likely to be a defect in the weld bead that initiates a crack (solid or gaseous inclusion, retassure, crack, etc.). These defects, combined with the notches caused by the more or less abrupt change in geometry due to the weld bead, are more significant than those in parts without welds.
Fatigue verification, which is used to prevent cracking, can be decisive in the case of bridges, runways, very slender structures exposed to wind, or hydraulic structures. Fatigue testing is not required for ordinary buildings subject to actions such as wind or snow, which are considered to be quasi-static.
To carry out a fatigue check, reference is generally made to standard NF EN 1993-1-9, "Design of steel structures – Part 1-9: Fatigue". However, other Eurocodes provide additional information on fatigue testing for structures that may be susceptible to fatigue, such as bridges, towers, masts, chimneys or runways.
The calculation of crack propagation is dealt with, but without much precision, in NF EN 1993-1-10, or rather in its reference document.
Having to refer to different parts of Eurocode 1 for fatigue loads, and to different parts of Eurocode 3 for the verification itself, makes understanding the verification process rather complex. That's why it's a good idea to bring together all the information on this subject in a single document.
This is the purpose of this article, which summarizes the principles of fatigue testing of structures susceptible to this phenomenon.
The term "fatigue limit state" has not been formalized in the Eurocodes. However, other documents may refer to it.
Exclusive to subscribers. 97% yet to be discovered!
You do not have access to this resource.
Click here to request your free trial access!
Already subscribed? Log in!
![](/assets/images/logo-eti-286623ed91fa802ce039246e516e5852.png)
The Ultimate Scientific and Technical Reference
KEYWORDS
steel | fatigue | metallic construction | cracking | standards | fracture mechanics | surface damage | Eurocodes
This article is included in
Public works and infrastructure
This offer includes:
Knowledge Base
Updated and enriched with articles validated by our scientific committees
Services
A set of exclusive tools to complement the resources
Practical Path
Operational and didactic, to guarantee the acquisition of transversal skills
Doc & Quiz
Interactive articles with quizzes, for constructive reading
Steel construction
Bibliography
Standards and norms
- Structural Eurocodes – Bases de calcul des structures, AFNOR - AFNOR NF EN 1990 (P06-100-1) - Mars 2003
- Execution of steel and aluminum structures – Part 2: technical requirements for the execution of steel structures, AFNOR - AFNOR NF EN 1090-2+A1 (P22-101-2) - octobre 2011
- Eurocode 1 "Actions on structures – Part 1-4: General actions – Wind actions, AFNOR - AFNOR NF EN 1991-1-4 (P06-114-1) - novembre 2005 ...
Websites
CEREMA – Centre d'études et d'expertise sur les risques, la mobilité et l'aménagement (Center for studies and expertise on risks, mobility and development)
IFSTTAR – Institut français des sciences et techniques des transports de l'aménagement et des réseaux
Exclusive to subscribers. 97% yet to be discovered!
You do not have access to this resource.
Click here to request your free trial access!
Already subscribed? Log in!
![](/assets/images/logo-eti-286623ed91fa802ce039246e516e5852.png)
The Ultimate Scientific and Technical Reference