In this study, a new adhesive contact model is built upon boundary element method (BEM) developed by Pohrt and Popov (2015). The strain energy release rate (SERR) on the edge of bonding interface evaluated using Virtual Crack Closure Technique (VCCT) which shown to have better accuracy weaker mesh-size dependency than closed-form SERR formula derived Popov. A composite delamination criterion pr...

A B S T R A C T Pump shafts used for power generation are susceptible to fatigue cracking while often in near-continuous operation. Technology based on torsional vibration is under development for condition-based assessment of shaft health. The focus of this paper is on the relationship between a crack, which propagated due to bending loads, and the torsional stiffness of the shaft. An analytic...

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There have been few studies to date describing fatigue-crack propagation thresholds under mixed-mode loading conditions in the presence of cracks, that are small as compared to the characteristic microstructural dimensions. To address this need, the variation in mixed-mode, high-cycle fatigue-crack growth thresholds with crack size is reported for a Ti-6Al-4V turbine blade alloy with a fine-gra...