Jiaoyan Li¹, Xianqiao Wang², James D. Lee¹

CMES-Computer Modeling in Engineering & Sciences, Vol.85, No.5, pp. 463-480, 2012, DOI:10.3970/cmes.2012.085.463

Abstract This paper presents a novel multiple time scale algorithm integrated with the concurrent atomic/atom-based continuum modeling, which involves molecular dynamic (MD) simulation and coarse-grained molecular dynamic (CG-MD) simulation. To capture the key features of the solution region while still considering the computational efficiency, we decompose it into two sub-regions in space and utilize the central difference method with different time steps for different sub-regions to march on in time. Usually, the solution region contains a critical field and a non-critical far field. For the critical field (named atomic region) modeled by MD simulation, a relatively small time step is used… More >

S. Tangaramvong¹, F. Tin-Loi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.42, No.3, pp. 217-256, 2009, DOI:10.3970/cmes.2009.042.217

Abstract Classical limit analysis is extended to include the effects of 2nd-order geometric and material nonlinearities, as well as the inclusion of limited ductility constraints. For the class of frame structures considered, the material constitutive model adopted can simultaneously accommodate the effects of combined axial and flexural force as well as local softening instability through the use of piecewise linearized yield surfaces. The main feature of the approach developed is to compute, in a single step, an upper bound to the maximum load. Corresponding displacements and stresses can be obtained as a by-product of the analysis. The problem is formulated as… More >

Wen Yi Lin¹, Kuo Mo Hsiao²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.2, pp. 259-272, 2003, DOI:10.3970/cmes.2003.004.259

Abstract The buckling and postbuckling behavior of spatial rods under different types of end torque and compressive axial force is investigated using finite element method. All coupling among bending, twisting, and stretching deformations for beam element is considered by consistent second-order linearization of the fully geometrically nonlinear beam theory. However, the third order term of the twist rate is also considered. An incremental-iterative method based on the Newton-Raphson method combined with constant arc length of incremental displacement vector is employed for the solution of nonlinear equilibrium equations. The zero value of the tangent stiffness matrix determinant of the structure is used… More >

W. Xia¹, Y.P. Feng², D.W. Zhao³

CMC-Computers, Materials & Continua, Vol.46, No.2, pp. 125-144, 2015, DOI:10.3970/cmc.2015.046.125

Abstract Postbuckling analysis of functionally graded ceramic-metal plates under temperature field is presented using finite element multi-mode method. The three-node triangular element based on the Mindlin plate theory is employed to account for the transverse shear strains, and the von-Karman nonlinear strain-displacement relation is utilized considering the geometric nonlinearity. The effective material properties are assumed to vary through the thickness direction according to the power law distribution of the volume fraction of constituents. The temperature distribution along the thickness is determined by one dimensional Fourier equations of heat conduction. The buckling mode shape solved from eigen-buckling analysis is adopted as the… More >

Tian-Zhong Wang¹, You-He Zhou^1,2

CMC-Computers, Materials & Continua, Vol.21, No.1, pp. 41-64, 2011, DOI:10.3970/cmc.2011.021.041

Abstract Based on the thermodynamic theory and the postulates of Jiles and Atherton, a general coupled magnetic-elastic-thermal free-energy model with hysteretic nonlinearity is established for Terfenol-D rods, in which the effect of Weiss molecular field is incorporated. The quantitative agreement between numerical simulation results predicted by the free-energy model and existing experimental data confirms the validity and reliability of the obtained nonlinear theoretical model, and indicates that the free-energy model can accurately capture the nonlinear hysteresis characteristic of Terfenol-D. Meanwhile, the free-energy model is employed to investigate the influences of mechanical stress and the temperature on the magnetostrictive effect of Terfenol-D… More >