A recently introduced method of crack representation as a distribution of three-dimensional Volterra dislocations is used in conjunction with two-dimensional dislocation dynamics simulations to study the brittle to ductile transition behavior of Ferritic Steels. The crack-tip plasticity zone is represented as an array of discrete dislocations emitted from crack-tip sources. The dislocations shi...

This paper is devoted to prove the existence of strong solutions for a brittle fracture model of quasi-static crack propagation in the two dimensional antiplane setting. As usual, the time continuous evolution is obtained as the limit of a discrete in time evolution by letting the time step tend to zero. The analysis rests on a density lower bound estimate for quasi-minimizers of Mumford-Shah t...

A method for the identification of multiple cracks based on Discrete Wavelet Transform is presented. The analysis is provided on beams made of polymeric laminate. The estimation of the crack locations is based on the evaluation of natural modal shapes of pre-cracked beams. The modal shapes were estimated experimentally using laser Doppler vibrometry. The dynamic response of multi-cracked beams ...

Dynamic crack growth along a bimaterial interface under impact shear loading is analyzed numerically. The material on each side of the bond line is characterized by an isotropic hyperelastic constitutive relation. A cohesive surface constitutive relation is also speci®ed that relates the tractions and displacement jumps across the bond line and that allows for the creation of new free surface. ...

We consider a brittle fracture taking account of selfequilibrated distributed stresses existing at microlevel in the absence of external forces. To determine how the latter can affect the crack equilibrium and growth, a model of a structured linearly elastic body is introduced, consisting of two equal symmetrically arranged layers (or half-planes) connected by an interface as a prospective crac...

We consider a brittle fracture taking account of self-equilibrated distributed stresses existing at microlevel in the absence of external forces. To determine how the latter can affect the crack equilibrium and growth, a model of a structured linearly elastic body is introduced, consisting of two equal symmetrically arranged layers (or half-planes) connected by an interface as a prospective cra...

that varies with distance, r, from the crack tip as r 1 2 . In this paper, a traction free plane stress wedge with a discrete cohesive zone along the intended crack-path is studied. Of interest is the in uence of the cohesive zone on the crack tip stress eld. Further, the in uence of the cohesive zone on the strain energy release rate is also investigated. Two example problems are studied; a do...

A numerical implementation of the eXtended Finite Element Method (X-FEM) to analyze crack propagation in a structure under dynamic loading is presented in this paper. The arbitrary crack is treated by the X-FEM method without re-meshing but using an enrichment of the classical displacement-based finite element approximation in the framework of the partition of unity method. Several algorithms h...