Two-parameter failure criterion for elastoplastic bodies with mode I cracks

Abstract

The generalized Dugdale crack model is used to formulate two-parameter failure criteria for the cases of quasibrittle state and developed plastic zones at a mode I crack tip. The failure criteria relate the fracture strength characteristics and the stress mode at the crack tip through the plastic constraint factor. The critical state of bodies with cracks under uni-and biaxial loading is analyzed in the cases of plane stress and plane strain using the Tresca and von Mises yield criteria. A small-scale yield criterion, which is an analytic relation between the critical stress intensity factor and T-stresses, is established

Plane-strain state of an elastoplastic body with a crack under mixed-mode loading

“…Comparing the parameters of the model under plane stress and plane strain makes it possible to reveal typical behavior for both small-scale and developed yielding at the crack tip. The obtained results underlie two-parameter fracture criteria for bodies with mode I cracks [11] invariant to the degree of triaxiality of the stress state at their front. The triaxiality of the stress state in the plastic zone was also taken into account in spatial problems for circular and elliptic cracks [3,4,12].…”

On loss of stability of a strip with two parallel macro-cracks under finite precritical deformation

“…One of the major fracture mechanisms for materials compressed along cracks is loss of stability of the equilibrium form around the cracks [7,9,[13][14][15]18]. The relevant studies, which employed the three-dimensional linearized theory of stability of deformable bodies (TLTSDB), assumed that the material occupied an infinite or semi-infinite region (see [11, 13, 14, 17, etc.] for a review of these studies).…”

Influence of tension along a crack on the plastic zone in an anisotropic body

“…A relevant boundary-value problem is solved numerically to study the behavior of the main plastic zone at the crack tip, a new plastic zone above the crack, and an additional plastic zone on the lateral surface, which merge to form a single plastic zone Keywords: anisotropic body, crack, plastic zone, merging of two plastic zones Introduction. Various crack models are widely used in elastoplastic fracture mechanics [5,[8][9][10][11][12][13][14][15]. These models can be justified only if the size and shape of plastic zones near cracks are known.…”