Shamsh Tabrez, Mira Mitra, S. Gopalakrishnan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.22, No.1, pp. 77-90, 2007, DOI:10.3970/cmes.2007.022.077

Abstract In this paper, wave propagation is studied in degraded composite beam due to moisture absorption. The obtained wave responses are then used for diagnosis of the degraded zone. Moisture absorption causes an irreversible hygrothermal deterioration of the material. The change in temperature and moisture absorption changes the mechanical properties. Thus this affects the structure in dimensional stability as well as material degradation due to reduction in mechanical properties. Here, the composite beam is modeled as Timoshenko beam using wavelet based spectral finite element (WSFE) method. The WSFE technique is especially tailored for simulation of wave propagation. It involves Daubechies scaling… More >

E.J. Sapountzakis¹, G.C. Tsiatas²

CMC-Computers, Materials & Continua, Vol.6, No.2, pp. 103-116, 2007, DOI:10.3970/cmc.2007.006.103

Abstract In this paper the general flexural-torsional buckling and vibration problems of composite Euler-Bernoulli beams of arbitrarily shaped cross section are solved using a boundary element method. The general character of the proposed method is verified from the formulation of all basic equations with respect to an arbitrary coordinate system, which is not restricted to the principal one. The composite beam consists of materials in contact each of which can surround a finite number of inclusions. It is subjected to a compressive centrally applied load together with arbitrarily transverse and/or torsional distributed or concentrated loading, while its edges are restrained by… More >

M.V.V.S. Murthy¹, S. Gopalakrishnan^2,3, P.S. Nair⁴

CMC-Computers, Materials & Continua, Vol.5, No.1, pp. 43-62, 2007, DOI:10.3970/cmc.2007.005.043

Abstract A refined 2-node, 7 DOF/node beam element formulation is presented in this paper. This formulation is based on higher order shear deformation theory with lateral contraction for axial-flexural-shear coupled deformation in asymmetrically stacked laminated composite beams. In addition to axial, transverse and rotational degrees of freedom, the formulation also incorporates the lateral contraction and its higher order counterparts as degrees of freedom. The element shape functions are derived by solving the static part of the governing equations. The element considers general ply stacking and the numerical results shows that the element exhibits super convergent property. The efficiency of the element… More >

M. C. Ray¹, L. Dong², S. N. Atluri³

CMC-Computers, Materials & Continua, Vol.47, No.3, pp. 143-177, 2015, DOI:10.3970/cmc.2015.047.143

Abstract This paper is concerned with the development of new simple 4-noded locking-alleviated smart finite elements for modeling the smart composite beams. The exact solutions for the static responses of the overall smart composite beams are also derived for authenticating the new smart finite elements. The overall smart composite beam is composed of a laminated substrate conventional composite beam, and a piezoelectric layer attached at the top surface of the substrate beam. The piezoelectric layer acts as the actuator layer of the smart beam. Alternate finite element models of the beams, based on an “equivalent single layer high order shear deformation… More >

Leiting Dong¹, Ahmed S. El-Gizawy², Khalid A. Juhany², Satya N. Atluri³

CMC-Computers, Materials & Continua, Vol.40, No.1, pp. 49-78, 2014, DOI:10.3970/cmc.2014.040.049

Abstract In this study, a simple 4-node locking-alleviated mixed finite element (denoted as CEQ4) is developed, for the modeling of homogeneous or functionally graded or laminated thick-section composite beam structures, without using higher-order (in the thickness direction) or layer-wise zig-zag theories of composite laminates which are widely popularized in current literature. Following the work of [Dong and Atluri (2011)], the present element independently assumes a 5-parameter linearly-varying Cartesian strain field. The independently assumed Cartesian strains are related to the Cartesian strains derived from mesh-based Cartesian displacement interpolations, by exactly enforcing 5 pre-defined constraints at 5 pre-selected collocation points. The constraints are… More >

W.F.Yuan¹, K.H.Tan ¹

CMC-Computers, Materials & Continua, Vol.13, No.1, pp. 49-62, 2009, DOI:10.3970/cmc.2009.013.049

Abstract A simple cellular automaton (CA) scheme is proposed to simulate heat conduction in anisotropic domains. The CA is built on random nodes rather than an irregular grid. The local rule used in the CA is defined by physical concepts instead of differential equations. The accuracy of the proposed approach is verified by classical examples. As an application of the proposed method, the CA approach is incorporated into fibre model which is widely used in finite element analysis to calculate the temperature distribution on the cross-section of composite beams. Numerical examples demonstrate that the proposed scheme can be conveniently applied to… More >

E.J. Sapountzakis¹, V.G. Mokos²

CMC-Computers, Materials & Continua, Vol.10, No.1, pp. 1-40, 2009, DOI:10.3970/cmc.2009.010.001

Abstract In this paper the boundary element method is employed to develop a displacement solution for the general transverse shear loading problem of composite beams of arbitrary constant cross section. The composite beam (thin or thick walled) consists of materials in contact, each of which can surround a finite number of inclusions. The materials have different elasticity and shear moduli and are firmly bonded together. The analysis of the beam is accomplished with respect to a coordinate system that has its origin at the centroid of the cross section, while its axes are not necessarily the principal bending ones. The transverse… More >