CRACKS in ductile single crystals are analyzed here for geometries and orientations such that twodimensional states of anti-plane shear constitute possible deformation fields. The crystals are modelled as ideally plastic and yield according to critical resolved shear stresses on their slip systems. Restrictions on the asymptotic forms of stress and deformation fields at crack tips are establish...

the problem of several finite moving cracks in a functionally graded material is solved by dislocation technique under the condition of anti-plane deformation. by using the fourier transform the stress fields are obtained for a functionallygraded strip containing a screw dislocation. the stress components reveal the familiar cauchy singularity at thelocation of dislocation. the solution is empl...

A model is provided for crack problem in a functionally graded semi-infinite plate under an anti-plane load. The characteristic of material behavior is assumed to change in a linear manner along the plate length. Also the embedded crack is placed in the direction of the material change. The problem is solved using two separate techniques. Primary, by applying Laplace and Fourier transformation,...

The problem of several finite moving cracks in a functionally graded material is solved by dislocation technique under the condition of anti-plane deformation. By using the Fourier transform the stress fields are obtained for a functionally graded strip containing a screw dislocation. The stress components reveal the familiar Cauchy singularity at the location of dislocation. The solution is em...

Abstract-Transonic interfacial crack growth in bimaterial systems is analysed, and the asymptotic field around the moving crack tip is obtained by the straightforward approach of analytic continuation. The power of singularity is less than l/2 for anti-plane shear deformation. For in-plane deformation, the power of singularity can be real or complex, depending on the speed of the crack tip. Acr...

Closed-form solutions for the transient dynamic problems of a suddenly applied anti-plane concentrated force and concentrated impulse near a crack are obtained. The various wave signals comprising the solutions are identified, and their behavior noted. The concentrated force solution is then employed as a Green's function to solve the important problem of arbitrary screw dislocation motion near...

We calculate elastic moduli and viscosities for media containing strongly interacting in-plane shear cracks. The cracks are randomly oriented or aligned, with equal length or a logarithmic size distribution. Our results from both a boundary element and a finite-element method suggest that the average moduli are best approximated by a differential, self-consistent model (DEM). Thus crack-tocrack...

This paper presents the fracture analyses conducted on the FAA/NASA stiffened and unstiffened panels using the STAGS (STructural Analysis of General Shells) code with the critical crack-tip-opening angle (CTOA) fracture criterion. The STAGS code with the “plane-strain” core option was used in all analyses. Previous analyses of wide, flat panels have shown that the high-constraint conditions aro...

An elastic-plastic analysis is performed for two problems relevant to fracture mechanics: a semi­ infinite body with an edge crack in a far out-of-plane shearing field and an infinite plate under plane stress conditions containing a finite line crack in a remote tensile field. Amplitudes of the dominant singularity in the plastic region at the crack tip, the plastic stress and strain intensity ...