Fatigue analysis of a plastic component in the window regulator system via considering the variation of fatigue characteristics

Spectral fatigue analysis is performed on the trimaran cross-deck structural detail. A global finite element (FE) model with local fine meshes at hot spot locations is built for the calculation of structural response. Three-dimensional linear potential flow theory and global FE analysis are used for wave load and stress transfer function calculations. Then, the hot spots’ fatigue damage is calculated, considering various factors influencing spectral analysis, which includes cycle counting correction factors, wave scatter diagram, and the distribution coefficient of wave headings. A full-scale model fatigue test is used to investigate the fatigue behavior of the cross-deck structural detail. Using the fatigue test data, the curve characteristic of the cross-deck structural detail is produced. Finally, the trimaran cross-deck structural detail’s fatigue characteristics are summarized and the effects of the factors influencing spectral fatigue analysis are reported.

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Lumbar Muscle Fatigue Analysis Using Sorensen Test with Different Upper Body Offload Conditions

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/1541931218621201 ◽

2018 ◽

Vol 62 (1) ◽

pp. 879-881

Author(s):

Rong Huangfu ◽

Sean Gallagher ◽

Phillip Whitley ◽

Richard Sesek ◽

Mark Schall ◽

...

Keyword(s):

Muscle Fatigue ◽

Surface Emg ◽

Fatigue Analysis ◽

Trunk Muscles ◽

Upper Body ◽

Median Frequency ◽

Lumbar Region ◽

Isometric Endurance ◽

Lumbar Muscle ◽

Fatigue Characteristics

The Sorensen test has been widely used in assessing the isometric endurance of trunk muscles. In this study, a modified Sorensen test was performed using four different upper body offload conditions (0%, 25% 50% and 75%) and surface EMG (sEMG) was used to determine fatigue characteristics in lumbar muscles. Results showed that the offloading of the upper body has a statistically significant impact on the slope of the EMG median frequency, which is representative of lumbar muscle fatigue responses. The first 25% offloading significantly decreased the fatigue response in the lumbar region. In addition, the 25% offload condition was significantly different from the 75% offload condition. However, the slopes of 25% and 50% offload conditions are not statistically different from each other and same for 50% and 75% offload conditions.

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SCF and Fatigue Analysis of Sphere-Nozzle Intersections With LTA

Volume 3: Design and Analysis ◽

10.1115/pvp2008-61176 ◽

2008 ◽

Cited By ~ 2

Author(s):

M. Qadir ◽

D. Redekop

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Fatigue Analysis ◽

Seismic Action ◽

Element Analysis ◽

Linear Elastic ◽

Uniform Wall ◽

Different Depths ◽

Fatigue Characteristics ◽

Ring Elements

A linear elastic finite element analysis (FEA) is carried out to determine the stress concentration factor (SCF) of a pressurized sphere-nozzle intersection. Nine-noded axi-symmetric 2D (ring) elements are used, and vessels without and with inner-wall local thinned areas (LTA) are considered. The SCF values obtained for vessels with uniform wall thickness are compared with previously published experimental and analytical results, and also with results from standard formulas given in the literature. An evaluation is made of the effect on the SCF of three types of inner-wall LTA; thinning in the nozzle, in the sphere, and in both components. As well, an evaluation is made of the effect on the SCF of growth of the LTA away from the intersection. A detailed parametric study is then carried out to determine the SCF for vessels with different depths of LTA. An elastic-plastic fatigue analysis for simulated seismic action is next carried out for some sample intersections, without and with LTA. The results provided are intended to contribute to the information available on the stress and fatigue characteristics of sphere-nozzle intersections with LTA.

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