Finite element analysis of curved thin-walled laminated channel structures

The objective of this paper is to develop an analytical procedure for dynamic characterization of thin-walled rounded channel beams made from laminated composites. To develop the analytical procedure, the thin wall beam theory for isotropic materials was extended for the laminated case. It is shown that the physical properties needed for modeling are the weighted average of the laminae properties. The corners of the c-channel beam are rounded for minimizing stress concentration and for ease of manufacturing. The cross-sectional properties of the rounded shape are calculated and reported. Once the beam model for the laminated composite beam is developed, it is used to set up dynamic equations for vibration analysis with combined bending and torsion. The variational formulation and the finite element procedure augmented by appropriate shape functions and boundary conditions leads us to the frequency equation which can be solved for system dynamics. Numerical examples are presented to validate the theory and the computer program. The results show that the theory is accurate and efficient. The program developed here can be used as the tool for the design of laminated channel beam structures of complex geometry.