The variation of the dynamic modulus on crack propagation modes

Papadopoulos, GA; Theocaris, PS

dc.contributor.author	Papadopoulos, GA	en
dc.contributor.author	Theocaris, PS	en
dc.date.accessioned	2014-03-01T01:07:01Z
dc.date.available	2014-03-01T01:07:01Z
dc.date.issued	1987	en
dc.identifier.issn	0376-9429	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/9745
dc.subject	Crack Propagation	en
dc.subject	Dynamical Processes	en
dc.subject	Elastic Modulus	en
dc.subject	Stress Field	en
dc.subject	Strain Energy Density	en
dc.subject.classification	Mechanics	en
dc.subject.other	DYNAMICS	en
dc.subject.other	FAILURE ANALYSIS	en
dc.subject.other	STRESSES - Strain	en
dc.subject.other	CRACK BIFURCATION PHENOMENA	en
dc.subject.other	CRACK PROPAGATION DYNAMICS	en
dc.subject.other	CRACK TIP STRESSES	en
dc.subject.other	STRESS INTENSITY FACTORS	en
dc.subject.other	MATERIALS	en
dc.title	The variation of the dynamic modulus on crack propagation modes	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/BF00015589	en
heal.identifier.secondary	http://dx.doi.org/10.1007/BF00015589	en
heal.language	English	en
heal.publicationDate	1987	en
heal.abstract	The variation of the elastic modulus due to the dynamic propagation of a crack and its influence on the instability of this dynamic process was studied, based on the theory of the T-criterion of failure of the material. Conditions for an eventual bifurcation of the moving crack were established according to this criterion. Furthermore, a comparison was undertaken between the results derived from the T-criterion and an improving modification of the S-criterion, called S2-criterion, which was based on the two-term expressions of the elastic stress field around the crack. While in the T-criterion the dilatational strain energy density, Tv, was calculated on the respective Mises elastic plastic boundary where the distortional component of strain energy density was constant, in the S2-criterion the core region was defined by the respective initial curve of the dynamic caustic. It was shown that the changes of the dynamic modulus and Poisson's ratio, depending on the relative crack velocity, were the main factors creating these instability- and bifurcation-phenomena of the moving cracks. Nomograms of the critical relative velocities of bifurcation versus the dynamic modulus and Poisson's ratio were plotted and compared satisfactorily with experimental data. It was indicated that, while the T-criterion gave satisfactory results all over the range of velocities and moduli, the S2-criterion gave comparable results only for brittle or semi-brittle cases. © 1987 Martinus Nijhoff Publishers.	en
heal.publisher	Martinus Nijhoff, The Hague/Kluwer Academic Publishers	en
heal.journalName	International Journal of Fracture	en
dc.identifier.doi	10.1007/BF00015589	en
dc.identifier.isi	ISI:A1987L227400004	en
dc.identifier.volume	35	en
dc.identifier.issue	3	en
dc.identifier.spage	195	en
dc.identifier.epage	219	en