Mechanical and Industrial Engineering Department-College of Engineering-Sultan Qaboos University
Development of a Finite Element Program for Thick Anisotropic
Laminated Composite Plates
Farooq Khalfan AL Jahwari
Abstract
Composite materials have become an indispensable material and are very widely used from
technically advanced products to consumer products. Laminated plates made of composite
material have found increasing applications in many industries. However, researchers are still
trying to understand the behavior of thick laminated composite plates for more safe and reliable
designs. The three dimensional elasticity theories are computationally expensive and become
intractable as the number of lamina increases. A simple 2-dimensional theory that accurately
describes the overall behavior of laminated plates seems to be a compromise between accuracy
and ease of analysis. The present research deals with such a theory known as higher order shear
deformation (HSDT) theory. It is an equivalent single layer theory based on the assumption of
parabolic variation of transverse shear strains across the thickness. The finite element method is
used as a solution methodology with 8-node serendipity element and seven degrees of freedom
per node. A computer program has been developed for static analysis based on first and higher
order shear deformation theories. The software is written in FORTRAN language. The accuracy
of results is demonstrated by comparing the results to three dimensional elasticity solutions and
those obtained by other researchers. It is found that the present higher order shear deformation
theory provides very accurate predictions of displacements and transverse shear stresses in
comparison to 3-dimensional elasticity theory. The results obtained are more accurate than
previously developed theories for thick plates. Moreover, the effects of transverse shear
deformation, material anisotropy, aspect ratio, fiber orientation and lamination sequence are
investigated