Crack propagation direction in a mixed mode geometry estimated via multi-parameter fracture criteria

Crack propagation direction in a mixed mode geometry estimated via multi-parameter fracture criteria

WoS Article

A numerical parametric study on the crack growth direction under mixed mode conditions (I + II) is introduced. An eccentric asymmetric four-point bending of a single edge notched beam specimen is considered as an example, since various levels of mode mixity can be thus obtained. The crack growth direction is estimated using the maximum tangential stress (MTS) criterion, the strain energy density (SED) criterion and the crack tip displacement (CTD) criterion. Multi-parameter fracture mechanics based on description of the stress and deformation fields in the cracked body by means of their approximation using several initial terms of the Williams power series is employed. It was found out that whereas the use of the CTD and SED criteria should be accurate enough even in their classical (or two-parameter) form for most geometries, the generalized form of the MTS criterion with at least four terms of the series should be applied. Thus it is able to describe the typical dependence of the initial kink angle on the distance from the crack tip where the criterion is applied.

A numerical parametric study on the crack growth direction under mixed mode conditions (I + II) is introduced. An eccentric asymmetric four-point bending of a single edge notched beam specimen is considered as an example, since various levels of mode mixity can be thus obtained. The crack growth direction is estimated using the maximum tangential stress (MTS) criterion, the strain energy density (SED) criterion and the crack tip displacement (CTD) criterion. Multi-parameter fracture mechanics based on description of the stress and deformation fields in the cracked body by means of their approximation using several initial terms of the Williams power series is employed. It was found out that whereas the use of the CTD and SED criteria should be accurate enough even in their classical (or two-parameter) form for most geometries, the generalized form of the MTS criterion with at least four terms of the series should be applied. Thus it is able to describe the typical dependence of the initial kink angle on the distance from the crack tip where the criterion is applied.

Near-crack-tip fields, mixed mode, crack propagation direction, Williams expansion, multi-parameter fracture criteria, finite element analysis

Near-crack-tip fields, mixed mode, crack propagation direction, Williams expansion, multi-parameter fracture criteria, finite element analysis

MALÍKOVÁ, L.; VESELÝ, V.; SEITL, S.

2017

18.01.2016

0142-1123

International Journal of Fatigue

2016

89

United Kingdom of Great Britain and Northern Ireland

99

107

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