Vibration Analysis of Composites

Abstract

Laminated composite plate structures find numerous applications in aerospace, military and automotive industries. The role of transverse shear is very important in composites, as the material is weak in shear due to its low shear modulus compared to extensional rigidity. Hence, an accurate understanding of their structural behaviour is required, such as deflections and stresses. In this paper, a number of finite element analyses have been carried out for various side- to- thickness ratios, aspect ratios and modulus ratios to study the effect of transverse shear deformation on deflection and stresses of laminated composite plates subjected to uniformly distributed load. The numerical results found out, on the deflections and stresses, that the effect of coupling is to decrease the deflections with the increase in the aspect ratio and modulus ratio and increase the stresses with the increase in the side- to- thickness ratio and modulus ratio. FEA of laminated composite plates shows deflections decrease with increasing aspect ratio and modulus ratio. Natural frequencies decrease with increasing number of cracks in composite beams. The analysis can be used to identify the presence of cracks in various composite beams by analyzing the first three frequency patterns of intact and cracked composite beams.