The Influence of the Internal Forces of the Buckling Modes on the Load-Carrying Capacity of Composite Medium-Length Beams under Bending (original) (raw)
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International Journal of Structural Stability and Dynamics, 2017
This paper introduces a new shell element formulation and investigates the buckling behavior of thin-walled beams composed of fiber-reinforced polymer composite-laminates, which is a primary design concern for thin-walled beams composed of fiber-reinforced polymer composite-laminates due to their slenderness. Although global buckling behavior can be captured using beam-column type two-node simple finite element formulations, shell-type more sophisticated elements are needed in order to be able to capture the effects due to cross-sectional deformations. Pursuit of an efficient shell element formulation continues to date and in this study, a new flat rectangular shell element formulation is developed for the buckling analysis of thin-walled composite-laminated members. The plate component of the shell is locking-free and based on the twist-Kirchhoff theory. For the membrane component of the shell element, variational formulation employing drilling degrees of freedom is adopted. Conver...
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Finite element method (FEM) is utilized to obtain numerical solution of the governing differential equations. Buckling analysis of rectangular laminated plates with rectangular cross – section for various combinations of boundary conditions and aspect ratios is studied. To verify the accuracy of the present technique, buckling loads are evaluated and validated with other works available in the literature. The good agreement with other available data demonstrates the reliability of finite element method used. New numerical results are generated for uniaxial and biaxial compression loading of symmetrically laminated composite plates; they are focused on the significant effects of buckling for various parameters such as boundary condition, aspect ratio and modular ratio. It was found that the effect of boundary conditions on buckling load increases as the aspect ratio increases for both uniaxial and biaxial compression loading. It was also found that, the variation of buckling load wit...
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