J.W. Chen¹, W. Liu¹, X.Y. Su^1,2

CMC-Computers, Materials & Continua, Vol.24, No.2, pp. 163-182, 2011, DOI:10.3970/cmc.2011.024.163

Abstract Truss-core sandwich plates are thin-walled structures comprising a truss core and two thin flat sheets. Since no direct analytical solution for the dynamic response of such structures exists, the complex three dimensional (3D) systems are idealized as equivalent 2D homogeneous continuous plates. The macroscopic effective bending and transverse shear stiffness are derived. Two representative core topologies are considered: pyramidal truss core and tetrahedral truss core. The first order shear deformation theory is used to study the flexural vibration of a simply supported sandwich plate. The buckling of the truss core plate on an elastic foundation More >

M. Al-Ajmi¹, A. Benjeddou²

CMC-Computers, Materials & Continua, Vol.23, No.3, pp. 265-286, 2011, DOI:10.3970/cmc.2011.023.265

Abstract A new discrete layer finite element (DLFE) is presented for electro-mechanically coupled analyses of moderately thick piezoelectric adaptive composite plates. The retained kinematics is based on layer-wise first-order shear deformation theory, and considers the plies top and bottom surfaces in-plane displacements and the plate transverse deflection as mechanical unknowns. The former are assumed in-plane Lagrange linear, while the latter is assumed in-plane full (Lagrange) quadratic; this results in a nine nodes quadrangular (Q9) DLFE. The latter is validated in free-vibrations, first numerically against ANSYS three-dimensional piezoelectric finite elements for a cantilever moderately thick aluminum plate… More >

M.F. Liu¹

CMC-Computers, Materials & Continua, Vol.22, No.2, pp. 97-128, 2011, DOI:10.3970/cmc.2011.022.097

Abstract A new invented Orthogonal Tapered Beam Functions (OTBFs) have been introduced in this paper and used in accordance with the Rayleigh-Ritz method to determine the natural frequencies and mode shapes of the non-uniform rectangular isotropic plates with varying thickness in one or two directions. The generation of the OTBFs is based on the static solution of a one-dimensional beam problem subjected to constant applied load, and then extends to an orthogonal or orthonomal infinite set of admissible functions by performing the three-term recurrence scheme. A wide range of non-uniform rectangular plate whose domain is referenced… More >

Dǎnuţ Receanu¹, Emil Budescu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.1, pp. 23-28, 2010, DOI:10.3970/icces.2010.014.023

Abstract The paper presents a new method for solving with precision of the differential equations of mechanical systems with two, three or more degrees of freedom. Always, the mechanical systems have coupled unknown quantities of differential equations. The method uncouples the unknown quantities using a graphic program: MATLAB- simulink. More >

A. Alaimo¹, A. Milazzo¹, C. Orlando¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.4, pp. 137-144, 2010, DOI:10.3970/icces.2010.015.137

Abstract The axial and flexural natural frequencies of magneto-electro-elastic bimorph beam devices are analyzed in the framework of the third-order shear deformation theory (TSDT). Although the assumption of parabolic transverse shear strain distribution along the thickness leads to higher order stress resultants the use of the TSDT allows to avoid the need for shear correction factor. Moreover, since the electric and magnetic potentials strictly depend on the shear strains, a more accurate modeling of the magneto-electric coupling can be achieved by expanding the kinematical model up to the cubic term. The natural frequencies for different mechanical More >

G. Davì¹, A. Milazzo¹, C. Orlando¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.4, pp. 129-136, 2010, DOI:10.3970/icces.2010.015.129

Abstract A dual reciprocity based boundary element approach for the analysis of magneto-electric laminates free vibration behavior is presented. The problem is formulated employing generalized displacements, that is displacements and electric and magnetic scalar potentials, and the corresponding generalized tractions. The generalized boundary integral representation is deduced by extending the reciprocity theorem to magneto-electro-elasticity problem and the multidomain boundary element technique is used to model multilayer structures. The magneto-electro-elastic static fundamental solutions are used jointly with the dual reciprocity method to transform the inertia domain integral into a boundary integral. Numerical results are presented focusing on More >

Wei-Xin Ren^1,2,3, Cong-Cong Su¹, Wang-Ji Yan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.70, No.1, pp. 67-92, 2010, DOI:10.3970/cmes.2010.070.067

Abstract A beam-arch segment assembly procedure is presented in this paper for the dynamic modelling and analysis of arch bridges. Such a beam-arch segment assembly is composed of different structural elements of arch bridges such as arch ribs (curved beams), suspenders, girders and floor beams. Based on the energy principle in structural dynamics, the stiffness matrix and mass matrix of such an assembly are formulated. The proposed procedure is then implemented to carry out the free vibration analysis of the Jian concrete filled tubular arch bridge. It is demonstrated that the proposed beam-arch segment assembly procedure More >

E. Carrera, S. Brischetto¹, M. Cinefra²

CMES-Computer Modeling in Engineering & Sciences, Vol.65, No.3, pp. 259-342, 2010, DOI:10.3970/cmes.2010.065.259

Abstract This paper investigates the problem of free vibrations of multilayered plates and shells embedding anisotropic and thickness polarized piezoelectric layers. Carrera's Unified Formulation (CUF) has been employed to implement a large variety of electro-mechanical plate/shell theories. So-called Equivalent Single Layer and Layer Wise variable descriptions are employed for mechanical and electrical variables;linear to fourth order expansions are used in the thickness direction z in terms of power of z or Legendre polynomials. Various forms are considered for the Principle of Virtual Displacements (PVD) and Reissner's Mixed Variational Theorem (RMVT) to derive consistent differential electro-mechanical governing… More >

M.K. Kang¹, E.H. Kim¹, M.S. Rim¹, I. Lee^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.64, No.3, pp. 227-250, 2010, DOI:10.3970/cmes.2010.064.227

Abstract An engineering model for predicting the behavior of shape memory alloy (SMA) wire is presented in this study. Piecewise linear relations between stress and strain at a given temperature are assumed and the mixture rule of Reuss bounds is applied to get the elastic modulus of the SMAs in the mixed phase. Critical stresses and strains of the start and finish of the phase transformation are calculated at a given temperature by means of a linear constitutive equation and a stress-temperature diagram. Transformation conditions based on the critical stresses are translated in terms of critical More >

Y. Inoue¹, R. Kobayashi¹, S. Ogata¹, T. Gotoh¹

CMES-Computer Modeling in Engineering & Sciences, Vol.63, No.2, pp. 137-162, 2010, DOI:10.3970/cmes.2010.063.137

Abstract Vibration of a single graphene and a pair of graphenes at micro meter scale induced by air flow is numerically simulated and examined by using a hybrid computational method starting from a microscopic level of description for the graphene. In order to bridge a huge gap in spatial and time scales in their motions, the carbon atoms of the graphene are represented by a small number of coarse grained particles, the fluid motion is described by the lattice Boltzmann equation and the momentum exchange at the boundary is treated by the time averaged immersed boundary… More >