• Cara, Girolamo Di

Abstract

The Sublaminate Generalized Unified Formulation (SGUF)is extended for the first time to the framework of Finite Element Method (FEM) for both displacement-based and mixed (RMVT) formulation. A substitute interpolation makes the developed FEs locking free and insensitive to mesh distortion. The possibility of exactly satisfying transverse stress boundary conditions for RMVT-based elements is also investigated for the first time. The flexibility and accuracy of the computational approach is demonstrated on linear static problems of sandwich plates and beams ranging from global bending response to local indentation problems. The challenging phenomenon experienced by laminated composite plates at free edges, known as free-edge effect, is also addressed.Free and forced vibration of sandwich beams and plates hosting viscoelastic material (VEM) layers are also investigated. The frequency-dependent behaviour of VEM is modelled according to the fractional derivatives Zener-type model or conventional series development based on the Generalised Maxwell model.Finally, stability considerations are addressed within the framework of the classical linearised stability analysis. The role of geometric and elastic properties on buckling loads and buckled shapes is emphasised.The onset of local instabilities in the face sheet of a sandwich panel under three-point flexion solicitation are also addressed.

Topics

• impedance spectroscopy
• laser emission spectroscopy
• composite