Distributed dislocation approach for cracks in couple-stress elasticity: Shear modes

Gourgiotis, PA; Georgiadis, HG

dc.contributor.author	Gourgiotis, PA	en
dc.contributor.author	Georgiadis, HG	en
dc.date.accessioned	2014-03-01T01:26:10Z
dc.date.available	2014-03-01T01:26:10Z
dc.date.issued	2007	en
dc.identifier.issn	0376-9429	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/17949
dc.subject	Couple-stress elasticity	en
dc.subject	Cracks	en
dc.subject	Distributed dislocations	en
dc.subject	Integral equations	en
dc.subject.classification	Mechanics	en
dc.subject.other	Couple-stress elasticity	en
dc.subject.other	Distributed dislocation	en
dc.subject.other	Crack tips	en
dc.subject.other	Cracks	en
dc.subject.other	Fracture mechanics	en
dc.subject.other	Integral equations	en
dc.subject.other	Microstructure	en
dc.subject.other	Numerical methods	en
dc.subject.other	Stresses	en
dc.subject.other	Elasticity	en
dc.title	Distributed dislocation approach for cracks in couple-stress elasticity: Shear modes	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/s10704-007-9139-5	en
heal.identifier.secondary	http://dx.doi.org/10.1007/s10704-007-9139-5	en
heal.language	English	en
heal.publicationDate	2007	en
heal.abstract	The distributed dislocation technique proved to be in the past an effective approach in studying crack problems within classical elasticity. The present work aims at extending this technique in studying crack problems within couple-stress elasticity, i.e. within a theory accounting for effects of microstructure. As a first step, the technique is introduced to study finite-length cracks under remotely applied shear loadings (mode II and mode III cases). The mode II and mode III cracks are modeled by a continuous distribution of glide and screw dislocations, respectively, that create both standard stresses and couple stresses in the body. In particular, it is shown that the mode II case is governed by a singular integral equation with a more complicated kernel than that in classical elasticity. The numerical solution of this equation shows that a cracked material governed by couple-stress elasticity behaves in a more rigid way (having increased stiffness) as compared to a material governed by classical elasticity. Also, the stress level at the crack-tip region is appreciably higher than the one predicted by classical elasticity. Finally, in the mode III case the corresponding governing integral equation is hypersingular with a cubic singularity. A new mechanical quadrature is introduced here for the numerical solution of this equation. The results in the mode III case for the crack-face displacement and the near-tip stress show significant departure from the predictions of classical fracture mechanics. © Springer Science+Business Media B.V. 2007.	en
heal.publisher	SPRINGER	en
heal.journalName	International Journal of Fracture	en
dc.identifier.doi	10.1007/s10704-007-9139-5	en
dc.identifier.isi	ISI:000254871000009	en
dc.identifier.volume	147	en
dc.identifier.issue	1-4	en
dc.identifier.spage	83	en
dc.identifier.epage	102	en