Effects Of Transverse Shear Deformation On Composite Beams With Various Laminate Configurations And Boundary Conditions

Abstract

Analytical methods are developed for determining deflection of composite beams under transverse load with various boundary conditions and laminate configurations. The present methods include development of expression for 1-D equivalent bending stiffness with and without presence of twisting curvature and prediction of the beam deflection accounting for transverse shear effect. Finite element analysis of 3-D ANSYS models is conducted by using Solid186 elements. The present analytical model is executed by using MATLAB program. Both analytical and FEM models were first validated by using isotropic material in the model and comparing the existing solutions. The composite beams with rectangular cross-section and small ratios of its length to its width and its width to its depth were selected for study. These conditions were chosen for enhancing the effect of the shear deformation. Various boundary conditions used for study include simply support, fixed at both ends, and cantilever beams under uniformly distributed or concentrated load, respectively. The maximum deflection of composite beams is investigated for transverse shear effects due to laminates with symmetric vs unsymmetrical layups and balanced vs unbalanced layups. Among all of the case studies, the analytical results agree well with the results obtained from FEM. It is found that for a given laminated beam under the same type of loading, effect of transverse shear on beam deflection is identical regardless with simply supported and fixed both ends but more pronounced for the case of cantilever beam. However, the effect of shear deformation on beam deflection due to stacking sequence is insignificant regardless of the type of loading.