Numerical investigations of corner singularities in cracked bodies

0092920 - ÚFM 2008 RIV CH eng J - Journal Article
Hutař, Pavel - Náhlík, Luboš - Knésl, Zdeněk
Numerical investigations of corner singularities in cracked bodies.
[Numerické stanovení rohové singularity v tělese s trhlinou.]
Key Engineering Materials. Roč. 348-349, - (2007), s. 377-380. ISSN 1013-9826.
[International Conference on Fracture and Damage Mechanics /6./. Funchal, Madeira, 17.07.2007-19.07.2007]
R&D Projects: GA ČR GP106/06/P239
Institutional research plan: CEZ:AV0Z20410507
Keywords : corner singularity * free surface * general singular stress concentrator * fatigue crack
Subject RIV: JL - Materials Fatigue, Friction Mechanics
Impact factor: 0.224, year: 2005

The influence of corner singularity on the distribution of the stresses around the crack front for a three-dimensional structure is described in this paper. The distribution of stress singularity through the thickness of the middle tension specimen provides us an indication of crack behaviour close to a free surface. An estimation of the region where the change of singularity exponent plays an important role in fatigue crack propagation rate was carried out. A decrease in fatigue crack propagation rate close to the free surface was found. The lower fatigue crack propagation rate in the boundary layer in comparison with the interior of the specimen leads to a change of intersecting angle between crack and free surface and depends on Poisson’s ratio.

V článku je popsán vliv rohové singularity na rozložení napětí v okolí vrcholu trhliny pro třídimenzionální konstrukci.Je sledováno rozložení rohové singularity po tloušťce vzorku. Byl proveden odhad oblasti, ve které dochází k významné změně exponentu singularity. Vlivem změny singularity po tloušťce dochází u volného povrchu k poklesu rychlosti šíření únavové trhliny.
Permanent Link: http://hdl.handle.net/11104/0153112