Download or read book Stress intensity Factor Equations for Cracks in Three dimensional Finite Bodies Subjected to Tension and Bending Loads written by J. C. Newman and published by . This book was released on 1984 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress intensity Factor Equations for Cracks in Three dimensional Finite Bodies written by and published by . This book was released on 1981 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress intensity Factor Equations for Cracks in Three dimensional Finite Bodies Subjected to Tension and Bending Loads written by and published by . This book was released on 1984 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Intensity Factor Equations for Cracks in Three Dimensional Finite Bodies written by JC. Newman and published by . This book was released on 1983 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents empirical stress-intensity factor equations for embedded elliptical cracks, semielliptical surface cracks, quarterelliptical corner cracks, semielliptical surface cracks at a hole, and quarterelliptical corner cracks at a hole in finite plates subjected to remote tensile loading. These equations give stress-intensity factors as a function of parametric angle, crack depth, crack length, plate thickness, and, where applicable, hole radius. The stress-intensity factors used to develop the equations were obtained from current and previous three-dimensional finite-element analyses of these crack configurations. A wide range of configuration parameters was included in the equations. The ratio of crack depth to plate thickness ranged from 0 to 1, the ratio of crack depth to crack length ranged from 0.2 to 2, and the ratio of hole radius to plate thickness ranged from 0.5 to 2. The effects of plate width on stress-intensity variations along the crack front also were included, but generally were based on engineering estimates. For all combinations of parameters investigated, the empirical equations were generally within 5 percent of the finite-element results, except within a thin "boundary layer" where the crack front intersects a free surface. However, the proposed equations are expected to give a good estimate in this region because of a study made on the boundary-layer effect. These equations should be useful for correlating and predicting fatigue crack growth rates as well as in computing fracture toughness and fracture loads for these types of crack configurations.

Download or read book Stress intensity Factor Equations for Cracks in Three dimensional Finite Bodies Subjected to Tension and Bending Loads written by J. C. Newman and published by . This book was released on 2018 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fracture Mechanics written by J. C. Lewis and published by ASTM International. This book was released on 1983 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Re evaluation of Finite element Models and Stress intensity Factors for Surface Cracks Emanating from Stress Concentrations written by and published by . This book was released on 1988 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plates and shells with cracks written by George C. Sih and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: This third volume of a series on Mechanies of Fraeture deals with eraeks in plates and shelIs. It was noted in Volume 2 on three-dimensional eraek problems that additional free surfaees can lead to substantial mathematical complexities, often making the analysis unmanageable. The theory of plates and shelIs forms a part of the theory of elasticity in which eertain physieal assumptions are made on the basis that the distanee between two bounded surfaees, either fiat or eurved, is small in eomparison with the overall dimen sions of the body. In modern times, the broad and frequent applieations of plate- and shell-like struetural members have aeted as a stimulus to whieh engineers and researchers in the field of fracture meehanies have responded with a wide variety of solutions of teehnieal importanee. These eontributions are covered in this book so that the reader may gain an understanding of how analytieal treat me nt s ofplates and shells containing initial imperfeetions in the form of eraeks are earried out. The development of plate and shell theories has involved long standing controversy on the eonsisteney of omitting eertain small terms and at the same time retaining others of the same order of magnitude. This defieieney depends on the ratio of the plate or shell thiekness, h, to other eharaeteristie dimensions and eannot be eompletely resolved in view of the approximations inherent in the transverse dependence of the extensional and bending stresses.

Download or read book Surface crack Growth written by Walter G. Reuter and published by ASTM International. This book was released on 1990 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the symposium (on title) held in Sparks, Nevada, April 1988. Twenty-two peer-reviewed papers are divided into sections on models and experiments (monotonic loading), and fatigue crack growth. Areas addressed include the differences in constraint for 2-D through-thickness cracks and 3-D surface

Download or read book A Re Evaluation of Finite Element Models and Stress Intensity Factors for Surface Cracks Emanating from Stress Concentrations written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-28 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: A re-evaluation of the 3-D finite-element models and methods used to analyze surface crack at stress concentrations is presented. Previous finite-element models used by Raju and Newman for surface and corner cracks at holes were shown to have ill-shaped elements at the intersection of the hole and crack boundaries. These ill-shaped elements tended to make the model too stiff and, hence, gave lower stress-intensity factors near the hole-crack intersection than models without these elements. Improved models, without these ill-shaped elements, were developed for a surface crack at a circular hole and at a semi-circular edge notch. Stress-intensity factors were calculated by both the nodal-force and virtual-crack-closure methods. Both methods and different models gave essentially the same results. Comparisons made between the previously developed stress-intensity factor equations and the results from the improved models agreed well except for configurations with large notch-radii-to-plate-thickness ratios. Stress-intensity factors for a semi-elliptical surface crack located at the center of a semi-circular edge notch in a plate subjected to remote tensile loadings were calculated using the improved models. The ratio of crack depth to crack length ranged form 0.4 to 2; the ratio of crack depth to plate thickness ranged from 0.2 to 0.8; and the ratio of notch radius to the plate thickness ranged from 1 to 3. The models had about 15,000 degrees-of-freedom. Stress-intensity factors were calculated by using the nodal-force method. Tan, P. W. and Raju, I. S. and Shivakumar, K. N. and Newman, J. C., Jr. Langley Research Center RTOP 505-63-01-05...

Download or read book Improved Stress intensity Factors for Semi elliptical Surface Cracks in Finite thickness Plates written by I. S. Raju and published by . This book was released on 1977 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Intensity Factor Solutions for Surface Cracks in Flat Plates Subjected to Nonuniform Stresses written by Mettu, SR. and published by . This book was released on 1994 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: The case of a surface crack in a flat plate has received a lot of attention from the fracture mechanics community because of its practical applicability as an idealization of a flaw in structures. Among all the solutions available, those of Raju and Newman seem to be the most accepted and cover the widest range of geometric parameters. These solutions are, however, known only for the cases of tensile and bending loads, and include the effect of finite width using an empirical equation. Residual stresses and more complex forms of loading lead to nonlinear stress distributions across the thickness in real structures. Attempts were made by a few researchers to provide solutions for arbitrary loading using the weight-function and other methods, but a comprehensive treatment of these solutions is not available. The objective of the present work is to provide complete solutions including the effect of finite width using direct tabular inter polation of the finite-element results and to demonstrate the accuracy of a weight-function approach for computing stress intensity factors for a cracked plate subject to arbitrary stresses across the thickness. The reference solutions used in the weight-function scheme were obtained using the three-dimensional finite-element method (FEM). The full range of geometric parameters such as the crack-length-to-width ratio 2c/W, the crack-depth-to-thickness ratio a/t, and the aspect ratio a/c was covered so that accurate interpolation and extrapolation could be made for any given geometry. Piecewise cubic Hermite interpolation was used to compute the quantities corresponding to intermediate values of the geometric parameters. The new solution was compared with the earlier Newman-Raju equation. The new solution in tabular form was then used directly in the weight-function method. The stress intensity factor solution developed here was incorporated into the fatigue crack growth program NASA/FLAGRO, which is widely used by the aerospace community.

Download or read book Three Dimensional Crack Problems written by M.K. Kassir and published by Springer. This book was released on 1975-04-30 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Surface Cracks at Hole by a 3 D Weight Function Method with Stresses from Finite Element Method written by and published by . This book was released on 1995 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Fracture Mechanics written by P. H. Wen and published by Computational Mechanics. This book was released on 1996 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work describes the formulation and numerical implementation of both two- and three-dimensional indirect boundary element methods (for example, the fictitious load method and the displacement discontinuity method). It also provides an analysis of crack problems in elastostatic and elastodynamic fracture mechanics, and methods for evaluating weight functions for dynamic problems.

Download or read book Analysis of Corner Cracks at Hole by a 3 D Weight Function Method with Stresses from Finite Element Method written by and published by . This book was released on 1995 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Three dimensional Elastic plastic Finite element Analyses of Constraint Variations in Cracked Bodies written by and published by . This book was released on 1993 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: