Crack opening displacement of a penny-shaped crack in an infinite body loaded by internal pressure over a circular area

1982 ◽  
Vol 20 (4) ◽  
pp. R135-R138 ◽  
Author(s):  
T. Fett
Keyword(s):  
Internal Pressure ◽  
Crack Opening Displacement ◽  
Crack Opening ◽  
Infinite Body ◽  
Opening Displacement ◽  
Circular Area ◽  
Penny Shaped Crack ◽  
Shaped Crack

Crack Opening Displacement Model for Through-Wall Axial Cracks in Cylinders

2013 ◽  
Author(s):  
Michael L. Benson ◽  
Bruce A. Young ◽  
Do-Jun Shim ◽  
Frederick W. Brust
Keyword(s):  
Internal Pressure ◽  
Crack Opening Displacement ◽  
Wall Thickness ◽  
Pipe Wall ◽  
Crack Opening ◽  
Pressure Loading ◽  
Opening Displacement ◽  
Piping Systems ◽  
Displacement Model ◽  
Leak Before Break

For piping systems, leak-before-break calculations rely on estimates of leak rates when postulated cracks grow through the pipe wall. The leak rate, in turn, depends on the crack opening dimensions. Previous work on crack opening displacement (COD) includes recent advances in COD estimates for circumferentially-oriented cracks in cylinders under tension, bending, and internal pressure loading conditions. This paper summarizes previous work in this area and reports on new solutions for COD in the case of axially-oriented cracks under internal pressure. The results reported here include COD solutions at three locations through the wall thickness for axial cracks.

Scattering by a horizontal subsurface penny-shaped crack

1986 ◽  
Vol 408 (1835) ◽  
pp. 277-294 ◽  
Keyword(s):  
Crack Opening ◽  
Resonance Phenomenon ◽  
Polar Coordinates ◽  
Axially Symmetric ◽  
Opening Displacement ◽  
Time Harmonic ◽  
Wave Resonance ◽  
Penny Shaped Crack ◽  
Rectangular Coordinates ◽  
Shaped Crack

The scattering by a horizontal subsurface penny-shaped crack subjected to axially symmetric loading is investigated. The formulation begins with deriving the response of a time harmonic point force in rectangular coordinates. Then, the integral representation and integral equations are converted into polar coordinates by applying the condition of axial symmetry. The results contain crack opening displacement (COD), stress intensity factors, scattered pattern and the frequency spectrum of the Rayleigh wave and the back-scattered longitudinal wave. Resonance phenomenon is compared with the plane strain case solved in an earlier paper.

Scattering by two penny-shaped cracks with spring boundary conditions

1993 ◽  
Vol 443 (1917) ◽  
pp. 183-201 ◽  
Keyword(s):  
Boundary Conditions ◽  
Crack Opening ◽  
Integral Equation Method ◽  
Neumann Series ◽  
Single Crack ◽  
Opening Displacement ◽  
Direct Integral ◽  
Spherical Waves ◽  
Penny Shaped Crack ◽  
Shaped Crack

The elastodynamic scattering by a penny-shaped crack with spring boundary conditions is investigated. The transition ( T ) matrix of the crack is determined and the usefulness of this is illustrated by considering also the scattering by two cracks. The T matrix of a single crack is first determined by a direct integral equation method which gives the crack-opening displacement and the integral representation which subsequently gives the scattered field expanded in spherical waves. Two cracks are considered by a multi-centred T matrix approach where matrix inverses are expanded in Neumann series. Rotation matrices are employed so that the cracks may have an arbitrary orientation. The back-scattered longitudinal far field amplitude is computed both in the frequency and time domain in a few cases and the effects due to multiple scattering are in particular explored.

A Dislocation Green’s Function for the Analysis of Multiple Coplanar Cracks or Cracks With Nonuniform Crack Fronts

1990 ◽  
Vol 57 (3) ◽  
pp. 589-595 ◽  
Author(s):  
M. T. Hanson
Keyword(s):  
Mixed Boundary ◽  
Crack Opening ◽  
Symmetry Plane ◽  
Mode I ◽  
Opening Displacement ◽  
External Crack ◽  
Present Solution ◽  
Penny Shaped Crack ◽  
Shaped Crack ◽  
Coplanar Cracks

This analysis considers the interaction between a penny-shaped crack or a circular external crack and a mode I “opening” point dislocation. The dislocation is taken to lie on the plane of the crack. Symmetry considerations allow the reduction to a mixed boundary value problem for a half space which is solved by well-known methods from potential theory. Closed-form expressions are obtained for the crack opening displacement, stress on the symmetry plane, and the mode I stress intensity factor around the internal or external crack. The use of the present solution for the accurate numerical treatment of cracks with large amplitude variations in the crack front curvature as well as cases of multiple coplanar cracks is outlined.

Sudden Twisting of a Penny-Shaped Crack

1972 ◽  
Vol 39 (2) ◽  
pp. 395-400 ◽  
Author(s):  
G. C. Sih ◽  
G. T. Embley
Keyword(s):  
Integral Transform ◽  
Crack Opening ◽  
Dynamic Crack ◽  
Static Case ◽  
Opening Displacement ◽  
Transient Problems ◽  
Penny Shaped Crack ◽  
Shaped Crack ◽  
Sudden Appearance ◽  
Square Root Singularity

A transient stress analysis for the problem of a torque applied suddenly to the surface of a penny-shaped crack in an infinite elastic body is carried out. The singular solution is equivalent to that of the sudden appearance of a crack in a body under torsion. Using an integral transform technique developed for this class of transient problems, the dynamic stresses near the periphery of the crack are found to have the same angular distribution and inverse square root singularity as in the static case. This character of the local solution prevails for all time only in a toroidal region extremely close to the crack border. Within this region, the stress intensity is found to vary with time, reaching a peak greater than the static value and subsequently oscillating about that value with decreasing amplitude. The dynamic crack-opening displacement field is also given for any instant of time after loading.

A mode I crack with multiple islands of ideal contact between the crack faces: An asymptotic model

2021 ◽  
pp. 108128652110214
Author(s):  
Ivan Argatov
Keyword(s):  
Crack Opening ◽  
Reduction Factor ◽  
Mode I ◽  
Asymptotic Model ◽  
Mode I Crack ◽  
Opening Displacement ◽  
Multiple Contacts ◽  
Scaling Hypothesis ◽  
Penny Shaped Crack ◽  
Crack Faces

The problem of a mode I crack having multiple contacts between the crack faces is considered. In the case of small contact islands of arbitrary shapes, which are arbitrarily located inside the crack, the first-order asymptotic model for the crack opening displacement is constructed using the method of matched asymptotic expansions. The case of a penny-shaped crack has been studied in detail. A scaling hypothesis for the compliance reduction factor is formulated.

Fatigue Crack Growth Tests on Glass Fibre Reinforced Polymer Matrix Composite

2005 ◽  
Vol 473-474 ◽  
pp. 189-194
Author(s):  
Zilia Csomós ◽  
János Lukács
Keyword(s):  
Cyclic Loading ◽  
Crack Opening Displacement ◽  
Matrix Composite ◽  
Glass Fibre ◽  
Crack Opening ◽  
Loading Conditions ◽  
Opening Displacement ◽  
Interfacial Cracks ◽  
Glass Fibre Reinforced ◽  
Number Of Cycles

E-glass fibre reinforced polyester matrix composite was investigated, which was made by pullwinding process. Round three point bending (RTPB) specimens were tested under quasi-static and mode I cyclic loading conditions. Load vs. displacement (F-f), load vs. crack opening displacement (F-v) and crack opening displacement range vs. number of cycles (ΔCOD-N) curves were registered and analysed. Interfacial cracks were caused the final longitudinal fracture of the specimens under quasi-static and cyclic loading conditions.

Uncertainty Characterization of the CrCOD Circumferential Crack Opening Displacement Module for xLPR

2015 ◽  
Author(s):  
Richard Olson ◽  
Paul Scott
Keyword(s):  
Crack Opening Displacement ◽  
Crack Opening ◽  
Opening Displacement ◽  
Crack Face ◽  
Pipe Surface ◽  
Circumferential Crack ◽  
The Us ◽  
Experimental Values ◽  
Metal Weld

The US NRC/EPRI xLPR (eXtremely Low Probability of Rupture) probabilistic pipe fracture analysis program uses deterministic modules as the foundation for the calculation of the probability of pipe leak or rupture as a consequence of active degradation mechanisms, vibration or seismic loading. The circumferential crack opening displacement module, CrCOD, estimates crack opening displacement (COD) at the inside pipe surface, at the mid-wall thickness location, and at the outside pipe surface using a combined tension/crack face pressure/bending GE/EPRI-like solution. Each module has an uncertainty beyond the uncertainty of the xLPR data inputs. This paper documents the uncertainty for CrCOD. Using 36 pipe fracture experiments, including: base metal, similar metal weld, and dissimilar metal weld experiments; bend only and pressure and bend loading; static and dynamic load histories; cracks that range from short to long, the uncertainty of the CrCOD methodology is characterized. Module uncertainty is presented in terms mean fit and standard deviation between prediction and experimental values.

Sign in / Sign up

Export Citation Format

Share Document