Free vibrations of laminated composite shells using the rotation-free plate elements based on Reddy’s layerwise discontinuous displacement model

The goal of this paper is to develop a computational model for the free vibration analysis of laminated composite shells with embedded delaminations. Laminated composite shells of different shape are modeled using the assembly of layered plate finite elements based on the Generalized Laminated Plate Theory of Reddy. Discontinuities in the displacement field are implemented using the Heaviside step functions. The material is assumed as orthotropic and linearly elastic. The solver is coded in MATLAB. For the generation of models and the visualization of results, GiD Pre/Post Processor is used. After the verification of the proposed model for the intact composite shells using the existing data from the literature, the effect of delamination size on the fundamental frequencies is investigated numerically. A variety of new results for delaminated shells is presented as a benchmark for future investigations.