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This article attempts an investigation on the free vibration behavior of the laminated composite angle ply shell experimentally and the obtained results are validated by laminated shell model based on modified higher order zigzag theory. The angle ply shell is modeled by placing six layers of 45° glass fiber laminae. The mechanical properties such as Poisson's ratio, Young's modulus and shear modulus are determined experimentally. The experimental procedure is performed using a vibration testing instrument by Bruel and Kjaer. The theoretical laminated shell is modeled by taking thickness coordinate to radius of curvature of shell ratio in the strain displacement relationship with shear-free conditions at free surfaces. For the theoretical computations of natural frequencies, a C0 finite element model with nine-noded quadrilateral shell element with seven degrees of freedom at each node has been chosen. Theoretical findings have been compared with experimental results and also with relevant published results in the existing literature. Moreover, extensive parametric studies have been performed to investigate the effect of geometric configurations and lamination schemes with different boundary properties on free vibration behavior of laminated shells, which will serve as benchmark solutions for future researchers. [ABSTRACT FROM AUTHOR]

The present theory deals with static and free vibration analyses based on higher order zigzag theory for laminated composite shells. The finite element shell model is developed considering the thickness coordinate to radius ratio (z/R) using nine noded isoparametric quadratic element. The proposed formulation satisfies the interlaminar stress continuity at the interface of laminae and zero shear boundary conditions at free surfaces. The response results obtained by the proposed formulations are compared with the published results. Moreover, new responses results of hyperbolic paraboloidal laminated shells are obtained using the present laminated shell theory and illustrated in the present study. [ABSTRACT FROM AUTHOR]