Document Type : Research Paper

Authors

Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

Laminated composite conical shells are used as components of aerospace, marine industries and civil engineering structures. In this research free vibration of grid stiffened composite conical shell with simply support boundary condition is studied. No study has yet been done on vibration analysis of these structures. Smeared method is employed to superimpose the stiffness contribution of the stiffeners with those of shell in order to obtain the equivalent stiffness parameters of the whole structure. The stiffeners are considered as a beam and support shear loads and bending moments in addition to the axial loads. Geodesic path is applied to the stiffeners. Equations were derived using classical shell theory of Donnell type and were solved using energy functional with the Rayleigh-Ritz method. A 3D finite element model was built using ABAQUS software. Results were compared and validated for grid stiffened structure with ABAQUS software. Comparisons and validations revealed good agreements. The effects of shell geometrical parameters and variations in the cross stiffeners angle on the natural frequencies were investigated.Results given are novel and can be used as a benchmark for further studies.

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