Deflection and Stress Analysis of Fibrous Composite Laminates

First order orthotropic shear deformation equations for the linear elastic bending response of rectangular
plates are introduced Their solution using a computer program in FORTRAN language based on finite differences
implementation of the Dynamic Relaxation DR method is outlined The convergence and accuracy of the DR
solutions for elastic linear response of isotropic orthotropic and laminated plates are established by comparison with
various exact and approximate solutions The present Dynamic Relaxation method DR coupled with Finite
Differences method FD shows a fairly good agreement with other analytical and numerical methods used in the
present study It was found that the DR linear theory program using uniform meshes can be employed in the analysis
of different thicknesses and length to side ratios for isotropic orthotropic and laminated fibrous plates under uniform
loads in a fairly good accuracy These comparisons show that the type of mesh used i e uniform or graded is
responsible for the considerable variations in the mid – side and corner stress resultants It is found that the
convergence of the DR solution depends on several factors including boundary conditions meshes size fictitious
densities and applied load It is also found that the DR linear theory can be employed with less accuracy in the
analysis of moderately thick and flat isotropic orthotropic or laminated plates under uniform loads It is also found
that the deflection of the plate becomes of an acceptable value when the length to thickness ratio decreases For
simply supported SS1 edge conditions all the comparison results confirmed that deflection depends on the direction
of the applied load and the arrangement of the layers