In the present paper, initial-boundary value problem of plane stress state of micropolar theory of elasticity is considered for orthotropic material in the domain of thin rectangle. General hypotheses are formulated, ...In the present paper, initial-boundary value problem of plane stress state of micropolar theory of elasticity is considered for orthotropic material in the domain of thin rectangle. General hypotheses are formulated, which are the qualitative results of the asymptotic method of integration of the stated initial-boundary value problem. On the basis of the accepted hypotheses general applied one-dimensional models of dynamics of bending deformation of micropolar orthotropic elastic thin bars with free fields of displacements and rotations are constructed with and without consideration of shear deformations. With the help of the constructed models different dynamic problems of micropolar bars can be studied. Here concrete problems of free and forced vibrations of hinged supported micropolar orthotropic elastic thin bar are studied. Numerical analysis is done and specific features of dynamic characteristics of micropolar material are revealed. Particularly, it is shown that there is a frequency of vibrations of the micropolar bar that does not depend on bar sizes.展开更多
In most structural applications, composite structures can be idealized as beams, plates or shells. The analysis is reduced from three-dimensional elasticity problem to a one-dimensional, or two-dimensional problem, ba...In most structural applications, composite structures can be idealized as beams, plates or shells. The analysis is reduced from three-dimensional elasticity problem to a one-dimensional, or two-dimensional problem, based on certain simplifying assumptions that can be made because the structure is thin. In this article is presented the mathematical model properly thin orthotropic plates, based on simplifying assumptions Love- Kirchhoff and small deformations. Proposed analytical solutions are considered both for solving equation orthotropic rectangular plates and for modal analysis, in the case of plates with clamped edges. The purposed solutions were analysed considering a FEM solution for comparison and the experimental test results.展开更多
文摘In the present paper, initial-boundary value problem of plane stress state of micropolar theory of elasticity is considered for orthotropic material in the domain of thin rectangle. General hypotheses are formulated, which are the qualitative results of the asymptotic method of integration of the stated initial-boundary value problem. On the basis of the accepted hypotheses general applied one-dimensional models of dynamics of bending deformation of micropolar orthotropic elastic thin bars with free fields of displacements and rotations are constructed with and without consideration of shear deformations. With the help of the constructed models different dynamic problems of micropolar bars can be studied. Here concrete problems of free and forced vibrations of hinged supported micropolar orthotropic elastic thin bar are studied. Numerical analysis is done and specific features of dynamic characteristics of micropolar material are revealed. Particularly, it is shown that there is a frequency of vibrations of the micropolar bar that does not depend on bar sizes.
文摘In most structural applications, composite structures can be idealized as beams, plates or shells. The analysis is reduced from three-dimensional elasticity problem to a one-dimensional, or two-dimensional problem, based on certain simplifying assumptions that can be made because the structure is thin. In this article is presented the mathematical model properly thin orthotropic plates, based on simplifying assumptions Love- Kirchhoff and small deformations. Proposed analytical solutions are considered both for solving equation orthotropic rectangular plates and for modal analysis, in the case of plates with clamped edges. The purposed solutions were analysed considering a FEM solution for comparison and the experimental test results.