• Structural Engineering and Mechanics
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• v.5 no.6
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• pp.817-837
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• 1997

In the present contribution an interface crack model is introduced which is capable of modelling crack initialisation and growth in aluminium as well as in Fibre Metal Laminates. Interface elements are inserted in a finite element mesh with a yield function which bounds all states of stress in the interface. Hardening occurs after a state of stress exceeds the yield stress of the material. The hardening branch is bounded by the ultimate stress of the material. Thereafter, the state of stress is reduced to zero while the inelastic deformations grow. The energy dissipated by the inelastic deformations in this process equals the fracture energy of the material. The model is applied to calculate the onset and growth of cracking in centre cracked plates made of aluminium and GLARE$^{(R)}$. The impact of the model parameters on the performance of the crack model is studied by comparisons of the numerical results with experimental data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.1
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• pp.206-214
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• 1998

When a crack meets bimaterial interface stress singularity depends on the elastic constants of the adjacent materials. In the present study we are going to describe the finite element formulation for problems with a crack to be embedded in the stiffer material$({\mu}_2/{\mu}_1)$. The cubic isoparametric singular element, represented by adequately shifting the mid-side nodes adjacent to the crack tip is constructed to enclose the crack tip. An alternative method to obtain the optimal position of the mid-side nodes of cubic isoparametric elements is presented. In addition, a proper definition for the stress intensity factors of a crack normal to bimaterial interface is provided. It is based upon near a tip displacement solutions. Models for numerical analysis are two dimensional elastic bodies with a through crack under plain strain. The results obtained are compared with the previous solutions.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.11
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• pp.2823-2827
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• 2000

The dynamic photoelasticity with the aid of Cranz-Shardin type high speed camera system is utilized to record the dynamically propagating behavior of an interface crack. This paper investigates determined the effects of the hole (exited on the path of the crack propagation) on the crack propagation behavior by comparing the experiment isochromatic fringes to the theoretical stress fields.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.127-131
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• 2000

The dynamic photoelasticity with the aid of Cranz-Shardin type high speed camera system is utilized to record the dynamically propagating behavior of an interface crack. This paper investigates determined the effects of the hole (existed on the path of the crack propagation) on the crack propagation behavior by comparing the experiment isochromatic fringes to the theoretical stress fields.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.3
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• pp.112-121
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• 1996

Applications of bonded dissimilar materials such as metal/ceramics and resin/metal joints, are very increasing in various industry fields. It is required to find crack propagation direction and path applying to the fracture mechanics on the bonded joint of dissimilar meterials. In this paper, crack propagation direction and path were simulated numerically by using boundary element method. Crack propagation angle is able to easily determine based on the maximum stress concept. Fracture tests of Al/Epoxy dissimilar materials with an interface crack are carried out under various mixed mode conditions by using the specimens of bonded scarf joints. It is found that the experimental results are well coincide with the analysis results of boundary element method.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.5 no.4
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• pp.53-62
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• 1996

Recently, ceramic / metal bonded joints have led to inccreasing use of structural materials such as automobile, heat engine in various industries. In this paper, a method to analyze an interface crack under both residual stresses and applied loading was proposed. and some results of boundary element method(BEM) analysis Were presented, Fracture thoughness tests of ceramic/metals bonded joints with an interface crack Were carried out, and the stress intensity factors of these joints Ware analyzed by BEM. Also crack propagtion direction was simulated numerically by using BEM. Crack propagation angle was able to easily determine based on the maximum stress concept. The prediction of fracture strength by the fracture thoughness of the ceramics/metals bonded joints was proposed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.3
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• pp.121-125
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• 2018

In this study, finite element analyses of crack propagation along a sinusoidal interface are performed by using cohesive elements. BK law is used for cohesive zone to consider mixed mode traction-separation relation at the crack tip on a sinusoidal interface of a double cantilever beam specimen. The shape of a sinusoidal interface crack and the cohesive strength and the cohesive energies in mixed mode cohesive laws are varied in numerical experiments, and load-displacement curves at the ends of a double cantilever beam specimen are obtained to investigate the crack propagation behavior along a sinusoidal interface.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.04a
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• pp.95-102
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• 1996

The stress intensity factor for an interface crack in dissimilar elastic and viscoelastic materials is derived and the time-domain boundary element analysis is performed. Numerical results show that the proposed method is very useful for the analysis of the interface crack in elastic and viscoelastic bimaterials.

• Journal of the Korean Society of Safety
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• v.2 no.3
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• pp.21-27
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• 1987

The effect of plastic deformation in an interfacial crack is considered. Yield zones are assumed to have the form of a strip along the interface. The crack is subjected to mode III loads at infinity and lies along the interface of two semi-infinite planes with different material properties. The size of the yield zones, the relation between the size of the yield zone and CTOD are obtained in a closed form solution. The J integral also can be obtained in a closed form Solution.

• Computational Structural Engineering
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• v.9 no.1
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• pp.93-99
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• 1996

In the particular situations where the crack is terminated at an interface of two materials, the order of stress singularity depends on the elastic constants which specify the properties of two materials. A multidomain boundary element technique is used to solve a crack normal to bimaterial interface. A correct order of shape function is used for displacement by using the isoparametric elements by shifting adequately the side nodes adjacent to this crack tip. A shape function containing the same order of singularity as that in the interface crack is also used for the interpolation of traction. Numerical testing of a binaterial with a crack normal to the interface is carried out with three-node elements. The results obtained are compared with the previous solutions.