Showing papers by "J. N. Reddy published in 1981"

Non-linear bending of thick rectangular, laminated composite plates

Abstract: A shear deformable theory accounting for the transverse shear (in the sense of Reissner-Mindlin's thick plate theory) and large rotations (in the sense of von Karman theory) is employed in the construction of a variational statement and associated finite element models of layered composite plates. Numerical results of deflections and stresses are presented for rectangular plates for various boundary conditions, loadings, stacking and orientation of layers, and material properties. Results are compared with other approximate results available in the literature.

Thermoelasticity of circular cylindrical shells laminated of bimodulus composite materials

Abstract: Closed-form and finite-element solutions are presented for the thermoelastic behavior of laminated composite shells. The material of each layer is assumed to be thermoelastically orthotropic and bimodular, that is, having different properties depending upon whether the fiber-direction normal strain is tensile or compressive. The formulations are based on the thermoelastic generalization of Dong and Tso 's laminated shell theory, which includes thickness shear deformations. The finite element used here has five degrees of freedom per node (three displacements and two bending slopes). Numerical results are presented for deflections and the positions of the neutral surfaces associated with bending along both coordinate directions. The closed-form and finite-element results are found to be in good agreement.

Vibration of Thick Rectangular Plates of Bimodulus Composite Material.

Abstract: : A finite-element analysis is carried out for small-amplitude free vibration of laminated, anisotropic, rectangular plates having arbitrary boundary conditions, finite thickness-shear moduli, rotatory inertia, and bimodulus action (different elastic properties depending upon whether the fiber-direction strain is tensile or compressive) The element has five degrees of freedom, three displacements and two slope functions, per node An exact closed-form solution is also presented for the special case of freely supported single-layer orthotropic and two-layer, cross-ply plates This provides benchmarks to evaluate the validity of the finite-element analysis Both solutions are compared with numerical results existing in the literature for special cases (all for ordinary, not bimodulus, materials) and good agreement is obtained (Author)

Bending of Thick Rectangular Plates Laminated of Bimodulus Composite Materials

Abstract: A mixed finite-element analysis is presented for static behavior of rectangular plates laminated of composite materials having finite transverse shear moduli and different elastic properties depending upon whether the fiber-direction strains are tensile or compressive. As a benchmark to assess the validity and accuracy of the finite-element analysis, a closed-form solution is given for a two-layer, cross-ply plate having all edges simply supported without in-plane restraint and subjected to sinusoidally distributed normal pressure. Numerical results obtained by the two methods are compared and found to agree quite well.

Finite-element modeling of layered, anisotropic composite plates and shells: A review of recent research

Abstract: Finite element papers published in the open literature on the static bending and free vibration of layered, anisotropic, and composite plates and shells are reviewed. A literature review of large-deflection bending and large-amplitude free oscillations of layered composite plates and shells is also presented. Non-finite element literature is cited for continuity of the discussion.