This paper concerns fatigue studies of polypropylene/glass-®bre thermoplastic composites produced from a bi-directional woven cloth of co-mingled E-glass ®bres and polypropylene ®bres with a ®bre volume fraction Vf of 0.338. The e€ect of lay-up design and load conditions on fatigue performance were investigated. The S-N curves, the rise in the temperature of the specimens, and the loss of sti€n...

This paper describes a finite element based method for simulating the effects of material removal, associated with fretting wear, on fretting fatigue parameters in a spline coupling. An incremental wear simulation technique is implemented with a single tooth finite element model of the coupling for symmetric loading, assuming equal wear on all teeth, using a comparatively coarse mesh model, for...

Guided wave structural health monitoring (SHM) is being considered to assess the integrity of plate-like structures for many applications. Prior research has investigated how guided wave propagation is affected by applied loads, which induce anisotropic changes in both dimensions and phase velocity. In addition, it is well-known that applied tensile loads open fatigue cracks and thus enhance th...

An integrated fatigue damage diagnosis and prognosis framework is proposed in this paper. The proposed methodology integrates a Lamb wave-based damage detection technique and a Bayesian updating method for remaining useful life (RUL) prediction. First, a piezoelectric sensor network is used to detect the fatigue crack size near the rivet holes in fuselage lap joints. Advanced signal processing ...

Fatigue-driven damage propagation is one of the most unpredictable failure mechanisms for a large variety of mechanical and structural systems subjected to cyclic and/or random operational loads during their service life. Therefore, monitoring the critical components of these systems, assessing their structural integrity, recursively predicting their remaining fatigue life (RFL), and providing ...

Considerable data implicate oxidative damage in influenza pathogenesis. We examined temporal changes in oxidative damage using accurate biomarkers in an adult cohort with acute influenza infection and their relationships with clinical parameters. Clinical information and blood samples were collected during their acute illness and 3 months later. A fatigue questionnaire was administered 3 months...

In this study, a novel structural fatigue prognosis method is developed to provide prompt, informed fatigue damage predictions of the structures based on strain gauge measurements at remote locations. The method is based on the structural responses reconstruction at the hot spots and a mechanism-based fatigue crack growth formulation. The structural responses measured from usage monitoring syst...

There have been numerous efforts to understand and control the resistance of materials to fracture by repeated or cyclic stresses. The micromechanical behaviours, particularly the distributions of stresses on the scale of grain size during or after mechanical or electrical fatigue, are crucial to a full understanding of the damage mechanisms in these materials. Whether a large microstress devel...