A database to evaluate stress intensity factors of elbows with throughwall flaws under combined internal pressure and bending moment

1994 ◽  
Vol 60 (1) ◽  
pp. 71-83 ◽  
Author(s):  
J Chattopadhyay ◽  
B.K Dutta ◽  
H.S Kushwaha ◽  
S.C Mahajan ◽  
A Kakodkar
Keyword(s):  
Stress Intensity ◽  
Internal Pressure ◽  
Stress Intensity Factors ◽  
Bending Moment ◽  
Intensity Factors

On the Stress Intensity Factors of Cracked Beams for Structural Analysis

2011 ◽  
Vol 488-489 ◽  
pp. 379-382 ◽  
Author(s):  
Erasmo Viola ◽  
Yong Li ◽  
Nicholas Fantuzzi
Keyword(s):  
Stress Intensity ◽  
Structural Analysis ◽  
Cross Section ◽  
Stress Intensity Factors ◽  
Circular Cross Section ◽  
Bending Moment ◽  
Intensity Factors ◽  
Close Approximation ◽  
Shear Forces ◽  
Cracked Beams

In this paper simple engineering methods for a fast and close approximation of stress intensity factors of cracked beams and bars, subjected to bending moment, normal and shear forces, as well as torque, are examined. As far as the circular cross section is concerned, comparisons are made on the base of numerical calculations. The agreement between the present results and those previously published is discussed. New formulae for calculating the stress intensity factors are proposed.

Mode III Stress Intensity Factors of Surface Crack in Round Bars

2011 ◽  
Vol 214 ◽  
pp. 192-196 ◽  
Author(s):  
Al Emran Ismail ◽  
Ahmad Kamal Ariffin ◽  
Shahrum Abdullah ◽  
Mariyam Jameelah Ghazali ◽  
Ruslizam Daud
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Crack Depth ◽  
Crack Tip ◽  
Bending Moment ◽  
Surface Cracks ◽  
Intensity Factors ◽  
Mode Iii ◽  
Element Analysis ◽  
Proposed Model

This study presents a numerical investigation on the stress intensity factors (SIF), K of surface cracks in round bars that were obtained under pure torsion loadings or mode III. ANSYS finite element analysis (FEA) was used to determine the SIFs along the crack front of surface cracks embedded in the solid circular bars. 20-node isoparametric singular elements were used around the crack tip by shifting the mid-side node ¼-position close to a crack tip. Different crack aspect ratio, a/b were used ranging between 0.0 to 1.2 and relative crack depth, a/D were ranged between 0.1 to 0.6. Mode I SIF, KI obtained under bending moment was used to validate the proposed model and it was assumed this proposed model validated for analyzing mode III problems. It was found that, the mode II SIF, FII and mode III SIF, FIII were dependent on the crack geometries and the sites of crack growth were also dependent on a/b and a/D.

Stress Intensity Factors for Plate Bending and Shearing Problems

1994 ◽  
Vol 61 (3) ◽  
pp. 719-722 ◽  
Author(s):  
A. T. Zehnder ◽  
Chung-Yuen Hui
Keyword(s):  
Stress Intensity ◽  
Stress Intensity Factors ◽  
Plate Theory ◽  
Infinite Plate ◽  
Bending Moment ◽  
Far Field ◽  
Intensity Factors ◽  
Arbitrary Angle ◽  
Cracked Plate ◽  
Finite Crack

Stress intensity factors for a finite crack in an infinite plate are calculated assuming Kirchhoff plate theory. Two problems are considered: a cracked plate subjected to uniform far-field shearing, and a cracked plate subjected to uniform far-field bending moment. In both cases the crack is oriented at an arbitrary angle to the axis of loading.

On the Determination of Stress Intensity Factors for Cracked Thick Cylinders

1983 ◽  
Vol 22 ◽  
Author(s):  
A P Parker ◽  
C P Andrasic
Keyword(s):  
Stress Intensity ◽  
Internal Pressure ◽  
Wall Thickness ◽  
Stress Intensity Factors ◽  
Material Removal ◽  
Simple Expression ◽  
Stress Fields ◽  
Intensity Factors ◽  
Fatigue Lifetime

ABSTRACTThe authors have previously published stress intensity (K) solutions for singly and multiply cracked thick cylinders with internal pressure and autofrettage stress fields. In this paper a method of obtaining K values for intermediate radii ratios is proposed. The method involves an approximate superposition procedure which models the removal (or addition) of cylinder material and is based on the nearest available radii ratio. The procedure is exact for very short crack lengths, and generally gives answers within 5% at crack lengths up to 20% of wall thickness (wherein most of the fatigue lifetime is expended) after removal of 20% of the wall thickness. A simple expression is given for the anticipated change in fatigue lifetime resulting from material removal.

Stress-Intensity Factors for Internal and External Surface Cracks in Cylindrical Vessels

1982 ◽  
Vol 104 (4) ◽  
pp. 293-298 ◽  
Author(s):  
I. S. Raju ◽  
J. C. Newman
Keyword(s):  
Stress Intensity Factor ◽  
Finite Element ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Internal Pressure ◽  
Stress Intensity Factors ◽  
Crack Depth ◽  
Surface Cracks ◽  
Stress Distributions ◽  
Intensity Factors

The purpose of this paper is to present stress-intensity factor influence coefficients for a wide range of semi-elliptical surface cracks on the inside or outside of a cylinder. The crack surfaces were subjected to four stress distributions: uniform, linear, quadratic, and cubic. These four solutions can be superimposed to obtain stress-intensity factor solutions for other stress distributions, such as those caused by internal pressure and by thermal shock. The results for internal pressure are given herein. The ratio of crack depth to crack length from 0.2 to 1; the ratio of crack depth to wall thickness ranged from 0.2 to 0.8; and the ratio of wall thickness to vessel radius was 0.1 or 0.25. The stress-intensity factors were calculated by a three-dimensional finite-element method. The finite-element models employ singularity elements along the crack front and linear-strain elements elsewhere. The models had about 6500 degrees of freedom. The stress-intensity factors were evaluated from a nodal-force method. The present results were also compared to other analyses of surface cracks in cylinders. The results from a boundary-integral equation method agreed well (±2 percent), and those from other finite-element methods agreed fairly well (±10 percent) with the present results.

Sign in / Sign up

Export Citation Format

Share Document