| Thin-walled beam structures are adopted as structural members in various fields of modern technology including aeronautical/aerospacial, naval, mechanical and civil ones.;With the advent of advanced composite material systems, there is a vital need to reformulate the classical theory of thin-walled beams in a wider framework.;This dissertation is intended to incorporate several essential effects which have a considerable importance for the rational design of composite thin-walled beam structures. These effects are the transverse shear deformation, the warping constraint, the secondary warping as well as the hygrothermal and the dynamic ones.;The field equations of laminated composite thin-walled beams of either open or closed single and multicell cross-sections are derived through the application of Hamilton's variational principle. The Laplace Transform technique is used to obtain exact solutions.;In this dissertation, the aeroelastic divergence instability of aircraft wings modelled as thin-walled beams as well as the eigenfrequency problem of cantilevered composite thin-walled beams of closed cross-section are considered in the framework of a refined theory incorporating non-classical effects.;The numerical results reveal the great role played by non-classical effects as well as by the tailoring technique applied to the problems studied in this dissertation. |
