Fatigue crack propagation in 3Y-TZP was investigated using controlled surface flaws. A unique growth law strongly dependent on the maximum stress intensity factor and quadratically dependent on the amplitude of the range of stress intensity factor was established. This growth law was found to apply for both surface flaws and internal flaws and could be used to predict fatigue lifetime. The pres...

In the present work, failure of a snow slab is analyzed by accounting Normal mode criteria. The analysis has been extended to include residual stress into the model (in addition to body forces). Intensity of crack energy release rate, and displacement components have been derived and their values have been estimated. The obtained results have been compared with the existing snow slab failure mo...

The accuracy of the Extended Finite Element Method (XFEM) in solving problems of straining plate with central crack is analyzed. Numerical solutions for displacements and stresses are compared with analytical solutions, while numerical solutions for stress intensity factor are compared with empirical solutions. The impact of the mesh density and near tip (NT) enrichment function are investigate...

This paper presents a finite element formulation of elasticity to model elastic fracture in composites with long aligned fibers. We have employed a B-bar type approach which is applicable to compressible as well as nearly incompressible material systems. An energy approach is undertaken to evaluate the stress intensity factor at the crack tip. The effects of strong intact bridging fibers, fiber...

In this paper, the solution of a moving Volterra-type screw dislocation in an orthotropic layer, bonded between two piezoelectric layers is obtained using complex Fourier transform. The dislocation solution is then employed as strain nuclei to derive singular integral equations for a medium weakened by multiple moving cracks. These equations, which are classified as, Cauchy singular equations, ...

It is natural to see the edge of nugget in spot weld joint as a sharp notch or crack. In this sense, driving force for fatigue crack growth can be estimated using fracture parameter such range stress intensity factor ΔK. research, Equivalent Stress Intensity Factor Range ΔKeq defined through integration field employed parameter. The primary advantage its simplicity computation. known that stren...

Background and Purpose—Lay people often mention stress as one of the most important risk factors for stroke. Stress might trigger a cerebrovascular event directly or could be associated with higher levels of blood pressure or an unfavorable lifestyle. To examine these possibilities, we analyzed the association between self-reported stress frequency and intensity and risk of stroke. Methods—Data...