Vibrational analyses of stiffened and unstiffened composite plates subjected to in-plane loads

Situations occur in which stiffened and unstiffened composite plates are required to withstand vibrational forces as well as in-plane stresses, consequently, to achieve good structural performance and an economical design, the plates must have high specific strength and stiffness. It is, therefore, necessary to undertake vibration and stability analyses and to design the system accordingly. The paper discusses the dynamic response of rectangular composite plates subjected to static in-plane compressive loads. To undertake the analyses, a finite element package was used to predict the dynamic behaviour and critical buckling loads of in-plane loaded plates; the latter had different aspect ratios. To verify the dynamic analytical analysis an experimental technique was used, however, the plates were not loaded to their critical load values. Relationships between the fundamental and six harmonic modes and the in-plane compressive loads for rectangular stiffened and unstiffened plates have been presented. The critical load values of the composite plates have been estimated from the stability and vibrational analyses.