Skip to Main content Skip to Navigation
Theses

Caractérisation expérimentale et modélisation du comportement en fatigue à grand nombre de cycles des structures soudées : application aux engins de manutention

Abstract : The structure of the handling equipment manufactured by Manitou encompassestwo welded assemblies, the chassis and the boom. These two structures are submitted tovariable and complex loading during the service life of the machines (10000 hours). Therefore,the fatigue design, of the welded structures, is a major challenge for Manitou. The mainobjective of this work consists of setting up a numerical sizing approach adapted to thestructures considered. First fatigue tests are conducted on different elementary weldedstructures, typical of the chassis and the boom, in order to assess the fatigue resistance ofthe welded structures manufactured by Manitou. Considering the material fatigue as a localphenomenon and the size of the chassis and the boom, a multiscale numerical approach ispresented. This approach makes it possible to access the mechanical fields at the weld toesand the weld root from a global shell element model. Then a fatigue criterion calculatedfrom local mechanical fields is identified, considering experimental fatigue test results. Thecriterion is then used to discuss the influence of the local geometry, the material behaviourand the residual stress field on the fatigue resistance of the welded structure. In particular, theinfluence of the local plasticity on the effect of the applied stress ratio is studied. Eventually,the proposed model is used to evaluate the stiffness behaviour and the fatigue resistanceof a more complex welded structure. Comparison with experimental results gives promising results.
Complete list of metadata

https://pastel.archives-ouvertes.fr/tel-03678238
Contributor : ABES STAR :  Contact
Submitted on : Wednesday, May 25, 2022 - 11:33:12 AM
Last modification on : Friday, May 27, 2022 - 3:23:41 AM

File

heyraud.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-03678238, version 1

Citation

Hugo Heyraud. Caractérisation expérimentale et modélisation du comportement en fatigue à grand nombre de cycles des structures soudées : application aux engins de manutention. Mécanique des matériaux [physics.class-ph]. HESAM Université, 2021. Français. ⟨NNT : 2021HESAE029⟩. ⟨tel-03678238⟩

Share

Metrics

Record views

52

Files downloads

23