The effect of anisotropy on post-buckling behavior of laminated plates using semi-energy finite strip method

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A Closed form solution for the buckling analysis of orthotropic reddy plate and prismatic plate structures

A closed-form solution based on the Reddy third-order shear deformation plate theory is proposed for the buckling of both flat and stiffened plates, with simply supported on two opposite edges. The equations governing the critical behaviour considering the full Green-Lagrange strain tensor and the second Piola-Kirchhoff stress tensor are derived using the principle of minimum potential energy. The general Levy-type approach is employed, and the accuracy and effectiveness of the proposed formulation is validated through direct comparison with analytical and numerical results available in the literature. The parametric analyses performed for different geometrical ratios show that the von Kármán hypothesis holds only for thin flat plates whereas it can significantly overestimate buckling loads for stiffened plates, for which the buckling mode entails comparable in-plane and out-of-plane displacement

A closed-form solution for buckling analysis of orthotropic Reddy plates and prismatic plate structures

This paper presents an analytical solution for elastic buckling problems of thick, composite prismatic plates subjected to uniaxial or biaxial compressive loads. Based on Reddy's third-order shear deformation theory and the Green-Lagrange deformation measure, the governing equations and natural boundary conditions of the plate are derived using Hamilton's principle, and solved analytically using the Navier and Levy-type solution methods. A large number of configurations are analyzed, and the effects of geometric and material properties on the buckling of both isotropic and orthotropic prismatic plates, as well as transversely anisotropic sandwich plates, are determined with a reduced computational effort. A comparison with results available in the literature, also determined by considering alternative plate models, shows the accuracy of the proposed approach

Constitutive and geometric nonlinear models for the seismic analysis of RC structures with energy dissipators

Nowadays, the use of energy dissipating devices to improve the seismic response of RC structures constitutes a mature branch of the innovative procedures in earthquake engineering. However, even though the benefits derived from this technique are well known and widely accepted, the numerical methods for the simulation of the nonlinear seismic response of RC structures with passive control devices is a field in which new developments are continuously preformed both in computational mechanics and earthquake engineering. In this work, a state of the art of the advanced models for the numerical simulation of the nonlinear dynamic response of RC structures with passive energy dissipating devices subjected to seismic loading is made. The most commonly used passive energy dissipating devices are described, together with their dissipative mechanisms as well as with the numerical procedures used in modeling RC structures provided with such devices. The most important approaches for the formulation of beam models for RC structures are reviewed, with emphasis on the theory and numerics of formulations that consider both geometric and constitutive sources on nonlinearity. In the same manner, a more complete treatment is given to the constitutive nonlinearity in the context of fiber-like approaches including the corresponding cross sectional analysis. Special attention is paid to the use of damage indices able of estimating the remaining load carrying capacity of structures after a seismic action. Finally, nonlinear constitutive and geometric formulations for RC beam elements are examined, together with energy dissipating devices formulated as simpler beams with adequate constitutive laws. Numerical examples allow to illustrate the capacities of the presented formulations.Postprint (published version