Free vibration of higher-order sandwich and composite arches, Part I: formulation

A higher-order refined model with seven degrees of freedom per node is presented in this paper for the free vibration analysis of composite and sandwich arches. The strain field is modeled through cubic axial, cubic transverse shear and linear transverse normal strain components. As the cross-sectional warping is accurately modeled by this theory, it does not require any shear correction factor. The stress-strain relationship is derived from an orthotropic lamina in a three-dimensional state of stress. The proposed higher-order formulation is validated, in this first part, through arches with various curvatures, aspect ratios, boundary conditions and materials

Transient dynamics of laminated beams: an evaluation with a higher-order refined theory

A higher-order refined model with seven degrees of freedom per node and cubic axial, quadratic transverse shear and linear transverse normal strain components is presented for the transient dynamic analysis of composite and sandwich beams. This shear correction coefficient free theory considers each layer of the beam to be in a state of plane stress. A special lumping scheme is employed for the evaluation of the diagonal mass matrix and a central difference predictor scheme is used to solve the dynamic equilibrium equation. The excellent performance of the higher-order model in comparison with the first-order theory is clearly brought out through numerical experiments

Free vibration of higher-order sandwich and composite arches, Part II: frequency spectra analysis

The frequency spectra of the higher-order model, for laminated arches, are identified through a novel process, proposed in this paper. Besides the basic spectra corresponding to axial, flexural and shear, presence of higher-order spectra is established. Coupled spectra of first-order and higher-order degrees of freedom, in various combinations, are identified. Based on this spectra identification framework, the frequencies of sandwich and composite arches, for various boundary conditions are classified and presented. Also, the role of curvature and aspect ratio on the fundamental frequency of arches with various end-conditions is investigated, in the second part of this paper.© Elsevie

On the flexural analysis of sandwich and composite arches through an isoparametric higher-order model

A higher-order arch model with seven degrees of freedom per node is proposed to study the deep, shallow, thick, and thin composite and sandwich arches under static loads. The strain field is modeled through cubic axial, cubic transverse shear, and linear transverse normal strain components. As the cross-sectional warping is accurately modeled by this theory, it does not require any shear correction factor. The stress-strain relationship is derived from an orthotropic lamina in a three-dimensional state of stress. The proposed formulation is validated through models with various curvatures, aspect ratios, boundary conditions, materials, and loading conditions