TY - JOUR

T1 - Elasto-plastic fracture criterion for structural components with sharp V-shaped notches

AU - Kurguzov, V. D.

AU - Shutov, A. V.

N1 - Funding Information: This work was supported by the Russian Science Foundation (Grant No. 19-19-00126). Publisher Copyright: © 2021, The Author(s), under exclusive licence to Springer Nature B.V. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/4

Y1 - 2021/4

N2 - Mode I fracture of plate specimens with sharp V-shaped notches is studied analytically and numerically. Within computations, elastic-perfectly plastic constitutive behaviour is assumed. The crack initiation from the tip of the V-shaped notch is described with the help of a modified Leonov–Panasyuk–Dugdale model using an additional parameter, namely, the diameter of the plasticity zone. Under small-scale yielding conditions in the presence of a singularity of the stress field in the vicinity of the V-shaped notch tip, a coupled fracture criterion is proposed. A strain-based fracture criterion is formulated at the real notch tip, and a force-based criterion operating with averaged normal stresses is considered at the fictitious crack tip. The diagrams of quasi-brittle fracture of specimens from structured material are constructed. The propagation of the plastic zone in the notched plates under quasi-static loading is simulated numerically. The plastic zone size in the vicinity of the V-shaped notch tip is assessed; in the limiting case, the V-notch degenerates into an edge crack. The generalized stress intensity factor for a crack growing from a sharp V-shaped notch is obtained by the finite element method. It is shown that under small-scale yielding, the analytical predictions of the critical load agree with the numerical results for a wide range of opening angles.

AB - Mode I fracture of plate specimens with sharp V-shaped notches is studied analytically and numerically. Within computations, elastic-perfectly plastic constitutive behaviour is assumed. The crack initiation from the tip of the V-shaped notch is described with the help of a modified Leonov–Panasyuk–Dugdale model using an additional parameter, namely, the diameter of the plasticity zone. Under small-scale yielding conditions in the presence of a singularity of the stress field in the vicinity of the V-shaped notch tip, a coupled fracture criterion is proposed. A strain-based fracture criterion is formulated at the real notch tip, and a force-based criterion operating with averaged normal stresses is considered at the fictitious crack tip. The diagrams of quasi-brittle fracture of specimens from structured material are constructed. The propagation of the plastic zone in the notched plates under quasi-static loading is simulated numerically. The plastic zone size in the vicinity of the V-shaped notch tip is assessed; in the limiting case, the V-notch degenerates into an edge crack. The generalized stress intensity factor for a crack growing from a sharp V-shaped notch is obtained by the finite element method. It is shown that under small-scale yielding, the analytical predictions of the critical load agree with the numerical results for a wide range of opening angles.

KW - Coupled criteria

KW - Crack initiation

KW - Critical load

KW - Fracture

KW - Pre-fracture zone

KW - V-shaped notch

UR - http://www.scopus.com/inward/record.url?scp=85103273246&partnerID=8YFLogxK

U2 - 10.1007/s10704-021-00530-1

DO - 10.1007/s10704-021-00530-1

M3 - Article

AN - SCOPUS:85103273246

VL - 228

SP - 179

EP - 197

JO - International Journal of Fracture

JF - International Journal of Fracture

SN - 0376-9429

IS - 2

ER -