Representations of Stress Intensity Factors by Path-Independent Integrals

1989 ◽  
Vol 56 (4) ◽  
pp. 780-785 ◽  
Author(s):  
Kuang-Chong Wu
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Body Force ◽  
Anisotropic Body ◽  
Crack Tip ◽  
Intensity Factors ◽  
Elastic Materials ◽  
Linear Elastic ◽  
Finite Crack

Stress intensity factors are represented by path independent integrals for linear elastic materials. Two types of representation are given. The first type of integrals are expressed by integration over contours surrounding a crack tip. Those of the second type are integrated over contours enclosing a finite crack. The path independent integrals are applied to determine the stress intensity factors due to a body force and a dislocation for a finite crack in an infinite anisotropic body.

Computation of Thermal Stress Intensity Factors for Bimaterial Interface Cracks Using Domain Integral Method

2009 ◽  
Vol 76 (4) ◽  
Author(s):  
Ratnesh Khandelwal ◽  
J. M. Chandra Kishen
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Thermal Loading ◽  
Thermal Stresses ◽  
Body Force ◽  
Bimaterial Interface ◽  
Intensity Factors ◽  
Linear Elastic ◽  
Domain Integral ◽  
Bimaterial Interface Crack

The concept of domain integral used extensively for J integral has been applied in this work for the formulation of J2 integral for linear elastic bimaterial body containing a crack at the interface and subjected to thermal loading. It is shown that, in the presence of thermal stresses, the Jk domain integral over a closed path, which does not enclose singularities, is a function of temperature and body force. A method is proposed to compute the stress intensity factors for bimaterial interface crack subjected to thermal loading by combining this domain integral with the Jk integral. The proposed method is validated by solving standard problems with known solutions.

Linear-Elastic and Elastoplastic Mode II and III Crack Tip Stress-Strain Fields in Cylindrical Specimens with Circumferential Crack

2009 ◽  
Vol 417-418 ◽  
pp. 321-324 ◽  
Author(s):  
Jana Horníková ◽  
Pavel Šandera ◽  
Jaroslav Pokluda
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Crack Front ◽  
Crack Tip ◽  
Mode Ii ◽  
Pure Mode ◽  
Intensity Factors ◽  
Linear Elastic ◽  
Circumferential Crack ◽  
Crack Tip Opening

A numerical analysis by means of the ANSYS code was performed in order to identify the ratio of both stress intensity factors and crack tip opening displacements for a cylindrical specimen with circumferential V-notch loaded by remote pure shear stress. This kind of loading produces pure mode II and III loading in four points on the circumferential crack front while the mix mode II+III exists in all other crack front points. In the linear-elastic range, the ratio of maximum values of mode III and mode II stress intensity factors was found to be . On the other hand, the ratio of crack tip opening displacements in the elastoplastic range approaches . These results can be used for the construction of fatigue crack growth rate curves in austenitic and ferritic steels measured in the near-threshold and near-fracture regions by means of a special testing device.

scholarly journals Dynamic Mixed Mode I-II Crack Kinking Under Oblique Stress Wave Loading in Brittle Solids

1990 ◽  
Vol 57 (1) ◽  
pp. 117-127 ◽  
Author(s):  
Chien-Ching Ma
Keyword(s):  
Stress Intensity ◽  
Stress Wave ◽  
Stress Intensity Factors ◽  
Crack Tip ◽  
Elastic Solid ◽  
Perturbation Parameter ◽  
Intensity Factors ◽  
Linear Superposition ◽  
Dynamic Stress Intensity Factors ◽  
Brittle Solids

The dynamic stress intensity factors of an initially stationary semi-infinite crack in an unbounded linear elastic solid which kinks at some time tf after the arrival of a stress wave is obtained as a function of kinking crack tip velocity v, kinking angle δ, incident stress wave angle α, time t, and the delay time tf. A perturbation method, using the kinking angle δ as the perturbation parameter, is used. The method relies on solving simple problems which can be used with linear superposition to solve the problem of a kinked crack. The solutions can be compared with numerical results and other approximate results for the case of tf = 0 and give excellent agreement for a large range of kinking angles. The elastodynamic stress intensity factors of the kinking crack tip are used to compute the corresponding fluxes of energy into the propagating crack-tip, and these results are discussed in terms of an assumed fracture criterion.

scholarly journals A Numerical Evaluation of SIFs of 2-D Functionally Graded Materials by Enriched Natural Element Method

2019 ◽  
Vol 9 (17) ◽  
pp. 3581 ◽  
Author(s):  
Jin-Rae Cho
Keyword(s):  
Stress Intensity ◽  
Functionally Graded Materials ◽  
Displacement Field ◽  
Stress Intensity Factors ◽  
Crack Tip ◽  
Functionally Graded ◽  
Intensity Factors ◽  
Graded Materials ◽  
Natural Element Method ◽  
Natural Element

This paper presents the numerical prediction of stress intensity factors (SIFs) of 2-D inhomogeneous functionally graded materials (FGMs) by an enriched Petrov-Galerkin natural element method (PG-NEM). The overall trial displacement field was approximated in terms of Laplace interpolation functions, and the crack tip one was enhanced by the crack-tip singular displacement field. The overall stress and strain distributions, which were obtained by PG-NEM, were smoothened and improved by the stress recovery. The modified interaction integral M ˜ ( 1 , 2 ) was employed to evaluate the stress intensity factors of FGMs with spatially varying elastic moduli. The proposed method was validated through the representative numerical examples and the effectiveness was justified by comparing the numerical results with the reference solutions.

Part-Elliptical Cracks Emanating From Open and Loaded Holes in Plates

1979 ◽  
Vol 101 (1) ◽  
pp. 12-17 ◽  
Author(s):  
T. E. Kullgren ◽  
F. W. Smith
Keyword(s):  
Finite Element ◽  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Crack Opening ◽  
Plate Thickness ◽  
Hole Diameter ◽  
Elastic Analysis ◽  
Intensity Factors ◽  
Linear Elastic ◽  
Elliptical Cracks

A linear elastic analysis using the finite element-alternating method is conducted for problems of single semi-elliptical and double quarter-elliptical cracks near fastener holes. Mode-one stress intensity factors are presented along the crack periphery for cases of open and loaded holes and crack opening displacements are calculated. Results are shown for a variety of crack geometries and loading conditions and for two ratios of hole diameter to plate thickness.

Crack tip stress intensity factors for a crack emanating from a semi-infinite notch with application to the avoidance of fatigue in complete contacts

2008 ◽  
Vol 223 (4) ◽  
pp. 789-794 ◽  
Author(s):  
A G Philipps ◽  
S Karuppanan ◽  
N Banerjee ◽  
D A Hills
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Crack Tip ◽  
Crack Development ◽  
Short Crack ◽  
Length Scale ◽  
Intensity Factors ◽  
Reference Length ◽  
Complete Contact ◽  
Crack Tip Stress

Crack tip stress intensity factors are found for the problem of a short crack adjacent to the apex of a notch, and lying perpendicular to one of the notch faces. Loading is represented by the two Williams eigensolutions, the ratio between which provides a reference length scale and permits a comprehensive display of the solution. The results are applied to the problem of a crack starting from the edge of a notionally adhered complete contact, and conditions for the avoidance of crack development are found.

Sign in / Sign up

Export Citation Format

Share Document