TY - EJOU
AU - Saito, Kei
AU - Hirashima, Tei
AU - Ma, Ninshu
AU - Murakawa, Hidekazu
TI - Characteristic Tensor for Evaluation of Singular Stress Field Under Mixed-Mode Loadings
T2 - Computer Modeling in Engineering \& Sciences
PY - 2020
VL - 122
IS - 2
SN - 1526-1506
AB - A characteristic tensor is defined using stress tensor averaged in a small
circular domain at the crack tip and multiplied by the root of domain radius. It possesses
the original stress tensor characteristics and has a simple relationship with conventional
fracture-mechanics parameters. Therefore, it can be used to estimate stress intensity
factors (SIFs) for cracks of arbitrary shape subjected to multiaxial stress loads. A
characteristic tensor can also be used to estimate SIFs for kinked cracks. This study
examines the relation between a characteristic tensor and SIFs to demonstrate the
correlation between the characteristic tensor and fracture-mechanics parameters.
Consequently, a single straight crack and a kinked crack of finite length existing in a twodimensional, infinite isotropic elastic body in a plane stress state, were considered to
investigate the properties of the characteristic tensor under mixed-mode loadings. To
demonstrate the practical utility of the characteristic tensor, the stress distribution
obtained through finite element analysis (FEA) was used to estimate mixed-mode SIFs,
and the values of estimated SIFs were compared with those obtained using an analytical
solution. Results demonstrate that SIFs estimated under mixed-mode loadings exhibit a
good agreement with the analytical values. This indicates that the proposed characteristictensor-based approach is effective in extracting features of singular stress fields at crack
tips, and can be employed to estimate values of fracture-mechanics parameters, such as
SIFs. Owing to its simplicity, the proposed approach can be easily incorporated in
commercial FE codes for practical applications to simulate the crack-growth problem
under both static and dynamic loading scenarios. The excellent applicability of the
characteristic tensor greatly contributes to efficiency of the design process in industries.
KW - Characteristic tensor
KW - stress-intensity factor
KW - mixed-mode loading
KW - kinked crack
DO - 10.32604/cmes.2020.08847