A Multiaxial Fatigue Analysis of Fretting Contact Taking Into Account the Size Effect

2008 ◽  
pp. 167-167-16 ◽  
Author(s):  
S Fouvry ◽  
P Kapsa ◽  
L Vincent
Keyword(s):  
Size Effect ◽  
Fatigue Analysis ◽  
Multiaxial Fatigue

Multiaxial fatigue analysis of orthotropic materials

2010 ◽  
Vol 107 (9) ◽  
pp. 369-375 ◽  
Author(s):  
C. Gaier ◽  
B. Unger ◽  
H. Dannbauer
Keyword(s):  
Fatigue Analysis ◽  
Multiaxial Fatigue ◽  
Orthotropic Materials

Spectral Fatigue Analysis of Plate Surface Hot-Spots: A Practical Solution to the Stress Direction Issue

2020 ◽  
Author(s):  
Fabien Bigot ◽  
Stéphanie Mougin
Keyword(s):  
Finite Element ◽  
Spectral Analysis ◽  
Fatigue Strength ◽  
Plane Stress ◽  
Hot Spots ◽  
Fatigue Analysis ◽  
Multiaxial Fatigue ◽  
The Other ◽  
Plate Surface ◽  
Practical Solution

Abstract Spectral Fatigue Analysis using coupled hydrodynamics and finite element models has now become a common practice for the fatigue strength assessment of offshore units, with established procedures given in Classification Rules. However, users are facing a practical issue that is almost never mentioned in the procedures. Indeed, many fatigue hot-spots are located on a plate surface, as opposed to plate edges. For such hot-spots, the finite element model results are the three components of the plane-stress stress tensor. Therefore, the outcome of the Spectral Fatigue Analysis is a set of three transfer functions (RAOs). On the other hand, our industry’s practice regarding the fatigue strength model is still the proven « design S-N curve » approach in combination with the Palmgren-Miner’s damage summation. As a consequence, today the engineer is left with no clear instruction about the proper way how to close this gap between the three stress RAOs on the one hand, and the single stress S-N curve on the other hand. If any advice is given, it is most often to consider the principal stresses, tentatively extending to spectral analysis the classification rule load cases approach. However, principal stress determination is a non-linear procedure that is not compatible with spectral analysis in frequency domain. Turning the spectral results into time domain to overcome this limitation is extremely costly and is not straightforward. Of course, a rational solution to this issue would be the adoption of a multiaxial fatigue damage criteria in lieu of the uniaxial S-N curve. But until such a multiaxial fatigue criteria is widely accepted in our industry, users have to square the circle, and force their stress tensor RAOs into the existing rule criteria. In this paper, a practical solution to reconcile plane stress results and conventional S-N curve criterion in spectral fatigue is proposed: the “facet approach “.

On the Evaluation of the Stress State in Rail Head for Assessing Fatigue Resistance

2014 ◽  
Vol 891-892 ◽  
pp. 1157-1162 ◽  
Author(s):  
Chung Lun Pun ◽  
Qian Hua Kan ◽  
Peter J. Mutton ◽  
Guo Zheng Kang ◽  
Wen Yi Yan
Keyword(s):  
Stress State ◽  
Fatigue Resistance ◽  
Fatigue Analysis ◽  
Multiaxial Fatigue ◽  
Rolling Contact ◽  
Single Parameter ◽  
Von Mises Stress ◽  
Stress Range ◽  
Rail Head ◽  
Von Mises

To search for a single parameter to evaluate the stress state in rail head during wheel/rail rolling contact situations, the stress-based and the strain based phenomenological approaches for multiaxial fatigue analysis can be considered as the candidates. Following the stress-based approach, the maximum von Mises stress range can be applied as a single parameter to evaluate the stress state in the rail head. However, the von Mises stress range only relies on the stress field in the rail head for the fatigue analysis, which is not sufficient for assessing the fatigue resistance of the rail steel. The Smith-Watson-Topper (SWT) method, the strain-based phenomenological approach for multiaxial fatigue analysis which considers stress, elastic strain and plastic strain components, is then adopted to study rolling contact fatigue in the rail head. Combining with the three-dimensional finite element modelling of a steady-state wheel/rail rolling contact, the numerical procedure to calculate the SWT parameter in the rail head is presented. The capability of the SWT method to predict the initiation of fatigue cracks in the rail head is confirmed in a case study. Consequently, the maximum SWT parameter is proposed as a single parameter to effectively evaluate the stress state in the rail head.

Multiaxial fatigue analysis on reeled deepwater steel catenary risers with girth weld defects

2014 ◽  
Vol 28 (6) ◽  
pp. 857-868
Author(s):  
He-zhen Yang ◽  
Jin-hong Ding ◽  
Qing-quan Li ◽  
Hua-jun Li
Keyword(s):  
Fatigue Analysis ◽  
Multiaxial Fatigue ◽  
Weld Defects ◽  
Steel Catenary Risers

Multiaxial fatigue analysis of complex welded joints in notch stress approach

2018 ◽  
Vol 204 ◽  
pp. 344-360 ◽  
Author(s):  
Wei Shen ◽  
Renjun Yan ◽  
Feng He ◽  
Shaomin Wang
Keyword(s):  
Welded Joints ◽  
Fatigue Analysis ◽  
Multiaxial Fatigue ◽  
Notch Stress
Sign in / Sign up

Export Citation Format

Share Document