G. Mishuris¹, A. Öchsner², G. Kuhn³

CMC-Computers, Materials & Continua, Vol.4, No.3, pp. 137-152, 2006, DOI:10.3970/cmc.2006.004.137

Abstract Nonclassical transmission conditions for dissimilar elastic structures with imperfect interfaces are investigated. The thin interface zone is assumed to be soft or stiff in comparison with the bonded materials and the transmission conditions for stiff interfaces are evaluated based on asymptotic analysis. The accuracy of the transmission conditions is clarified not only in terms of asymptotic estimate, but, which is especially important for users, also in values by accurate FEM calculations. The ranges of applicability of the conditions are discussed. More >

Shen Yubin¹, Xie Huicai^1,2, Den Wei¹

CMC-Computers, Materials & Continua, Vol.3, No.2, pp. 49-54, 2006, DOI:10.3970/cmc.2006.003.049

Abstract Bonding an overlay of new concrete onto the damaged concrete is a usual repair method. Because of the different shrinkage rate of the new and old concrete, restrained shrinkage cracks will appear in the new concrete. The cracks will reduce durability and strength of the repaired structure. A new repair method using an interface layer of carbon fiber reinforced cement mortar between new and old concrete was developed in this paper. The new method was found to be very effective in reducing shrinkage cracking of repaired beams and slabs. Comparing with normal repaired beams, the More >

M. S. Alam¹, M.A. Wahab^1,2

Structural Durability & Health Monitoring, Vol.1, No.3, pp. 171-184, 2005, DOI:10.3970/sdhm.2005.001.171

Abstract Fatigue life of curved structural joints in ship structures under constant amplitude cyclic loading has been studied in this research. A new approach for the simulation of fatigue crack growth in welded joints has been developed and the concept has been applied to welded curved butt-joints. The phenomena of crack propagation and interface debonding can be regarded as the formation of new surfaces. Thus, it is possible to model these problems by introducing the mechanism of surface formation. In the proposed method, the formation of new surface is represented by interface element based on the… More >

X. Neil Dong^1,2, Xiaohui Zhang¹, X. Edward Guo¹

Molecular & Cellular Biomechanics, Vol.2, No.2, pp. 63-68, 2005, DOI:10.3970/mcb.2005.002.063

Abstract In human cortical bone, cement lines (or reversal lines) separate osteons from the interstitial bone tissue, which consists of remnants of primary lamellar bone or fragments of remodeled osteons. There have been experimental evidences of the cement line involvement in the failure process of bone such as fatigue and damage. However, there are almost no experimental data on interfacial properties of cement lines in human cortical bone. The objective of this study is to design and assemble a precision and computer controlled osteon pushout microtesting system, and to experimentally determine the interfacial strength of cement… More >

Christopher A. Lemmon^1,2, Nathan J. Sniadecki³, Sami Alom Ruiz^1,3, John L. Tan, Lewis H. Romer^2,4,5, Christopher S. Chen^3,4

Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 1-16, 2005, DOI:10.3970/mcb.2005.002.001

Abstract The interplay of mechanical forces between the extracellular environment and the cytoskeleton drives development, repair, and senescence in many tissues. Quantitative definition of these forces is a vital step in understanding cellular mechanosensing. Microfabricated post array detectors (mPADs) provide direct measurements of cell-generated forces during cell adhesion to extracellular matrix. A new approach to mPAD post labeling, volumetric imaging, and an analysis of post bending mechanics determined that cells apply shear forces and not point moments at the matrix interface. In addition, these forces could be accurately resolved from post deflections by using images of More >

Jin Yeon Cho¹, Jae Mo An², You Me Song¹, Seungsoo Lee¹, Dong Whan Choi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.1, pp. 1-18, 2005, DOI:10.3970/cmes.2005.009.001

Abstract A displacement welding technique is proposed to carry out coupled analysis of the integrated whole model which consists of independently modeled finite element substructures. In the proposed method, the incompatible displacement fields in the interfaces of independently modeled substructures are directly welded together through a blended function that is newly defined in the transient region of mismatching interface. To construct the blended function, the moving least squares function, which does not require well-defined nodal connectivity, is utilized along with the original finite element shape function. The meshless character of the moving least squares function makes More >

Yaxin Song¹, D. Michael McFarland¹, Lawrence A. Bergman¹, Alexander F. Vakakis²

CMES-Computer Modeling in Engineering & Sciences, Vol.10, No.2, pp. 153-170, 2005, DOI:10.3970/cmes.2005.010.153

Abstract A general interface element is developed for dynamic response analysis of structures with jointed interfaces, which can account for damping due to both impact and friction. Contact effects are included through a segment-to-segment contact model which considers the stick-slip-slap behavior at every point along the joint interface. A nonlinear friction law is adopted at the interface to describe microscopic relative motion due to the deformation of the asperities on the interface. Numerical examples demonstrate that the general joint interface element is capable of accounting for both friction and impact damping in jointed interfaces, as well More >

G. Mishuris¹, A. Öchsner², G. Kuhn³

CMC-Computers, Materials & Continua, Vol.2, No.4, pp. 227-238, 2005, DOI:10.3970/cmc.2005.002.227

Abstract FEM-evaluation of imperfect transmission conditions has been performed for a modelling problem of an elastic structure with a thin intermediate interface. Very good correlations with theoretical results have been obtained. Additionally, the possible error connected with introducing the transmission conditions instead of the intermediate zone has been estimated depending on mechanical properties of the zone. More >

M.V. Bayas^1,1, K.Schulten^2,2, D. Leckb,^3,3

Molecular & Cellular Biomechanics, Vol.1, No.2, pp. 101-112, 2004, DOI:10.3970/mcb.2004.001.101

Abstract The force-induced dissociation of the strand dimer interface in C-cadherin has been studied using steered molecular dynamics simulations. The dissociation occurred, without domain unraveling, after the extraction of the conserved trypthophans (Trp2) from their respective hydrophobic pockets. The simulations revealed two stable positions for the Trp2 side chain inside the pocket. The most internal stable position involved a hydrogen bond between the ring Ne of Trp2 and the backbone carbonyl of Glu90. In the second stable position, the aromatic ring is located at the pocket entrance. After extracting the two tryptophans from their pockets, the More >

Dan Givoli¹

CMES-Computer Modeling in Engineering & Sciences, Vol.5, No.6, pp. 497-514, 2004, DOI:10.3970/cmes.2004.005.497

Abstract Very thin layers with material properties which significantly differ from those of the surrounding medium appear in a variety of applications. Traditionally there are two extreme ways of handling such layers in finite element analysis: either they are fully modelled or they are totally ignored. The former option is often very expensive computationally, while the latter may lead to significant inaccuracies. Here a special technique of modeling thin layers is devised within the framework of the finite element method. This technique constitutes a prudent compromise between the two extremes mentioned above. The layer is replaced More >