K.I. Tserpes¹, A.S. Koumpias¹

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.2, pp. 169-182, 2012, DOI:10.32604/cmes.2012.083.169

Abstract In this work, a comparison between a cohesive zone model and a continuum damage model in predicting the mode-I fracture behavior of adhesively bonded joints is performed on the basis of reliability and applicability. The cohesive zone model (CZM) is based on an exponential traction law characterizing the behavior of the interface elements. The continuum damage model (CDM) is based on the stiffness degradation of adhesive elements imposed by a damage parameter. Both models have been implemented by means of a 3D finite element model. Mode-I fracture behavior of the bonded joints was characterized using… More >

Bin Li¹, Guo-biao Yang¹, Qi-rong Zhu², Fan Ni²

CMC-Computers, Materials & Continua, Vol.21, No.2, pp. 107-118, 2011, DOI:10.3970/cmc.2011.021.107

Abstract In this paper, digital image correlation method (DICM) is employed to measure the shear behavior of the spot welding specimens and the ones using adhesive under quasi-static lap shear testing. The images of the specimens' surfaces are captured in real-time by CCD and corresponding computer system. DICM is subsequently used to obtained strain by correlating the images captured before and after deformation. Then, both force-displacement curves and stress-strain curves of the specimens including the cracking load are obtained. The results and analysis show that the mechanical properties of specimens using adhesive compared with the spot More >

L. Távara¹, V. Manticˇ ¹, E. Graciani¹, J. Cañas¹, F. París¹

CMES-Computer Modeling in Engineering & Sciences, Vol.58, No.3, pp. 247-270, 2010, DOI:10.3970/cmes.2010.058.247

Abstract The problem of a crack in a thin adhesive layer is considered. The adherents may have orthotropic elastic behavior which allows composite laminates to be modeled. In the present work a linear elastic-brittle constitutive law of the thin adhesive layer, called weak interface model, is adopted, allowing an easy modeling of crack propagation along it. In this law, the normal and tangential stresses across the undamaged interface are proportional to the relative normal and tangential displacements, respectively. Interface crack propagation is modeled by successive breaking of the springs used to discretize the weak interface. An… More >

M. Kashtalyan^1,2, Y.A. Zhuk³

CMES-Computer Modeling in Engineering & Sciences, Vol.57, No.1, pp. 1-30, 2010, DOI:10.3970/cmes.2010.057.001

Abstract The paper investigates propagation of stationary plane longitudinal and transverse waves along the layers in adhesively bonded multilayered structures for MEMS applications in the presence of residual stresses. The multilayered structure is assumed to consist of the infinite amount of the periodically recurring layers made of two different materials possessing significantly dissimilar properties: conductive metal layer and insulating adhesive layer. It is assumed that the mechanical behaviour of both materials is nonlinear elastic and can be described with the help of the elastic Murnaghan potential depending on the three invariants of strain tensor. The problem More >

J. Useche, P. Sollero, E.L. Albuquerque¹, L. Palermo²

Structural Durability & Health Monitoring, Vol.4, No.2, pp. 107-116, 2008, DOI:10.3970/sdhm.2008.004.107

Abstract The fracture analysis of cracked thick plates repaired with adhesively bonded composite patches using a boundary element formulation is presented. The shear deformable cracked isotropic plate was modeled using the dual boundary method. In order to model the repair, a three parameter boundary element formulation was established. This formulation is based on Kirchhoff's theory for symmetric layer composite plates and considers the transversal deflection and two in-plane rotations. Interaction forces and moments between the cracked plate and the composite repair were modeled as distributed loading, and discretized using continuous and semi-discontinuous domain cells. Coupling equations, More >

J. Useche¹, P. Sollero², E.L. Albuquerque², L. Palermo³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.3, pp. 175-182, 2008, DOI:10.3970/icces.2008.006.175

Abstract The computational fracture analysis of cracked thick plates repaired with adhesively bonded composite patches using a boundary element formulation is presented. The shear deformable cracked isotropic plate was modeled using the Reissner's plate theory. In order to model the repair, a three parameter boundary element formulation, based on Kirchhoff's theory for symmetric layered composite plates was established. Interaction forces and moments between the cracked plate and the composite repair were modeled as distributed loads. Coupling equations, based on kinematic compatibility and equilibrium considerations for the adhesive layer, were established. In-plane shear-deformable model with transversal stiffness More >

Shaohua Chen^*

Molecular & Cellular Biomechanics, Vol.5, No.2, pp. 97-106, 2008, DOI:10.3970/mcb.2008.005.097

Abstract Recently, contact mechanics has been widely used to get some understanding of the biological adhesion mechanisms, such as cell-cell adhesion, insects' adhesion and locomotion. JKR theory is usually adopted as a basis, in which the interaction of molecules is considered in contrast to the classical Hertz solution. In this paper, two problems are summarized, which may give some insights to cells or bio-molecules sensitivity to environmental signals: (1) cell reorientation on a stretched substrate; (2) spontaneous detachment between cells or bio-molecules under the variation of environmental signals. The intention here is only to illustrate the… More >

Hai Ngu^*, Lan Lu^*, Sara J. Oswald^*, Sarah Davis^*, Sumona Nag^*, Frank C-P Yin^†

Molecular & Cellular Biomechanics, Vol.5, No.1, pp. 69-82, 2008, DOI:10.3970/mcb.2008.005.069

Abstract Endothelial cells subjected to cyclic stretching change orientation so as to be aligned perpendicular to the direction of applied strain in a magnitude and time-dependent manner. Although this type of response is not the same as motility, it could be governed by motility-related factors such as substratum adhesiveness and actin-myosin contractile level. To examine this possibility, human aortic endothelial cells (HAEC) were uniaxially, cyclically stretched on silicone rubber membranes coated with various concentrations of fibronectin, collagen type IV and laminin to produce differing amounts of adhesiveness (measured using a radial flow detachment assay). Cells were… More >

Song-Jeng Huang^1,2, Lin-Wei Chiu²

CMES-Computer Modeling in Engineering & Sciences, Vol.34, No.1, pp. 1-32, 2008, DOI:10.3970/cmes.2008.034.001

Abstract The composite sandwich plate is one of the most common composite structures. Local stress concentrations can be caused by localized bending effects where a load is introduced. Although a sandwich structure with an insert is one of the classical load bearing structures, little work has been conducted on the adhesive layers or inserts. This study involves a linear elasticity analysis of five-layer sandwich plates with ``through-the-thickness'' inserts, using sandwich plate theory to analyze deformation behavior. Governing equations are formulated as partial differential equations, which are solved numerically using the multi-segment integration method. Sandwich plates with More >

J. Mohan¹, D. Carolan¹, N. Murphy¹, A. Ivankovic¹, D. Dowling¹

Structural Durability & Health Monitoring, Vol.3, No.2, pp. 81-86, 2007, DOI:10.3970/sdhm.2007.003.081

Abstract The aim of this work is to investigate the influence of a variety of plasma treatments on the surface properties of an epoxy-based composite material and to establish a relationship between these properties and the subsequent mechanical behaviour of adhesively bonded joints. To this end, specimens were subjected to three different types of plasma treatment: two short treatments (2min) of He and He plus O₂, and one long treatment (15min) of He plus O₂. The variation in surface energy of the composite specimens was examined in each case over a period of up to 3 days… More >