Transverse bending of rectangular plates with a single-edge crack or double-edge cracks.

Abstract A continuous cracked beam vibration theory is developed for the lateral vibration of cracked Euler-Bernoulli beams with single-edge or double-edge cracks. The Hu-Washizu-Barr variational formulation was used to develop the differential equation and the boundary conditions of the cracked beam as an one-dimensional continuum. The displacement field about the crack was used to modify the stress and displacement field throughout the bar. The crack was modelled as a continuous flexibility using the displacement field in the vicinity of the crack, found with fracture mechanics methods. The results of three independent evaluations of the lowest natural frequency of lateral vibrations for beams with a single-edge crack are presented: the continuous cracked beam vibration theory developed here, the lumped crack beam vibration analysis, and an asymptotic solution. Experimental results from aluminum beams with fatigue cracks are very close to the values predicted. A steel beam with a double-edge crack was also investigated with the above mentioned methods, and results compared well with experimental data.

Download Full-text

Stress Intensity Factors of Eccentric Cracks in Bi-Material Plates

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.663.98 ◽

2014 ◽

Vol 663 ◽

pp. 98-102 ◽

Cited By ~ 2

Author(s):

Al Emran Ismail

Keyword(s):

Stress Intensity ◽

Stress Intensity Factors ◽

Edge Crack ◽

Central Line ◽

Mode I ◽

Single Edge ◽

Intensity Factors ◽

Finite Element Software ◽

Edge Cracks ◽

Plain Strain

This paper presents the effect of eccentric cracks on the behavior of stress intensity factors (SIF) of single edge crack in bi-material plates. According to literature, it is found that most of the research conducted previously more on central single edge crack and it is well understood. However, not many research conducted on the eccentric stress intensity factor of single edge crack in bi-material plates. In order to evaluate the SIFs of eccentric edge cracks, ANSYS finite element software is used to model plain strain single edge crack in a plate subjected mode I loadings. The present SIFs are then validated with the existing central crack and it is well agreed to each others. According to the present results, it is found that mode I SIFs decreased insignificantly and mode II SIFs decreased asymptotically when the crack situated away from the central line. As expected all types of SIFs increased when crack length is increased.

Download Full-text

Single-Edge Crack in Rectangular Sheet Subjected to End Rotations

Journal of Applied Mechanics ◽

10.1115/1.3625146 ◽

1966 ◽

Vol 33 (3) ◽

pp. 689-691 ◽

Cited By ~ 2

Author(s):

J. M. Bloom

Keyword(s):

Stress Intensity ◽

Edge Crack ◽

Hilbert Problem ◽

Center Line ◽

Single Edge ◽

Intensity Factors ◽

Length Width ◽

Edge Cracks ◽

Distribution Of Stress ◽

Riemann Hilbert Problem

Stress-intensity factors for single-edge cracks in rectangular sheets subjected to end rotations about the center line of the rectangle are investigated. The problem of the distribution of stress around the crack tip is reduced to the solution of a Riemann-Hilbert problem. Numerical results are presented for varying crack lengths and length/width ratios of the sheet.

Download Full-text

Mode I stress intensity factor with various crack types

Frattura ed Integrità Strutturale ◽

10.3221/igf-esis.59.31 ◽

2021 ◽

Vol 16 (59) ◽

pp. 471-485

Author(s):

Ehab Samir Mohamed Mohamed Soliman

Keyword(s):

Stress Intensity Factor ◽

Stress Intensity ◽

Intensity Factor ◽

Edge Crack ◽

Von Mises Stress ◽

Mode I ◽

Single Edge ◽

Cracked Plate ◽

Double Edge ◽

Von Mises

Presence of cracks in mechanical components needs much attention, where the stress field is affected by cracks and the propagation of cracks may be occurred causing the damage. The objective of this paper is to present an investigation of crack type effect on crack severity in a finite plate. Three cases of cracked plate with three different types of cracks are assumed in this work, i.e., single edge crack, center crack and double edge crack. 2D numerical models of cases of cracked plate are established in finite element analysis (FEA), ANSYS software by adopting PLANE 183 element. Values of FEA mode I stress intensity factor SIF and Von-Mises stress at crack apex are determined for cases of cracked plate under tensile stress with different values. To identify the crack severity, the comparison of FEA results for different cracked cases is made. The comparison showed that, single edge cracked plate (SECP) has the maximum values of mode I SIF and Von-Mises stress at crack apex, i.e. the greatest crack severity is considered. Also, values of FEA Von-Mises stress at crack apex for center cracked plate (CCP) are moderate and for double edge cracked plate (DECP) are the minimum. Besides, in case of high crack lengths, it is found that, FEA results of mode I SIF in case of (CCP) are higher than those of in case of (DECP). Consequently, crack severity is considered as moderate in case of (CCP) and the minimum in case of (DECP). Empirical formulas are used to approximately estimate mode I SIF for all the case studies of cracked plate in this study and the results are compared to those of FEA. A good agreement between analytical and FEA results has been showed by this comparison.

Download Full-text

A weight function for the single edge crack based on approximative displacement fields

Theoretical and Applied Fracture Mechanics ◽

10.1016/0167-8442(87)90042-5 ◽

1987 ◽

Vol 8 (3) ◽

pp. 169-172 ◽

Cited By ~ 6

Author(s):

T. Fett

Keyword(s):

Weight Function ◽

Edge Crack ◽

Single Edge ◽

Displacement Fields

Download Full-text

Comparison of Strip Yield and Net Section Plasticity Models for a Bar in Bending With a Single Edge Crack

Volume 2: Computer Technology and Bolted Joints ◽

10.1115/pvp2017-66238 ◽

2017 ◽

Author(s):

Wolf Reinhardt ◽

Don Metzger

Keyword(s):

Edge Crack ◽

Large Scale ◽

Stress Singularity ◽

Crack Tip ◽

Small Scale ◽

Single Edge ◽

Yield Model ◽

Strip Yield Model ◽

Crack Tip Plasticity ◽

Stress And Deformation

The strip yield model is widely used to describe crack tip plasticity in front of a crack. In the strip yield model the stress in the plastic zone is considered as known, and stress and deformation fields can be obtained from elastic solutions using the condition that the crack tip stress singularity vanishes. The strip yield model is generally regarded to be valid to describe small scale plasticity at a crack tip. The present paper examines the behavior of the strip yield model at the transition to large-scale plasticity and its relationship to net section plasticity descriptions. A bar in bending with a single edge crack is used as an illustrative example to derive solutions and compare with one-sided and two-sided plasticity solutions.

Download Full-text