MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES

The vibration and stability of axially loaded sandwich cylindrical shells with the functionally graded (FG) core with and without shear stresses and rotary inertia resting Pasternak foundation are investigated. The dynamic stability is derived based on the first order shear deformation theory (FSDT) including shear stresses. The axial load and dimensionless fundamental frequency for FG sandwich shell with shear stresses and rotary inertia and resting on the Pasternak foundation. Finally, the influences of variations of FG core, elastic foundations, shear stresses and rotary inertia on the fundamental frequencies and critical axial loads are investigated

The dynamic stability of a nonhomogeneous orthotropic elastic truncated conical shell under a time dependent external pressure

WOS: 000174076100006In this research, the dynamic stability of an orthotropic elastic conical shell, with elasticity moduli and density varying in the thickness direction, subject to a uniform external pressure which is a power function of time, has been studied. After giving the fundamental relations, the dynamic stability and compatibility equations of a nonhomogeneous elastic orthotropic conical shell, subject to a uniform external pressure, have been derived. Applying Galerkin's method, these equations have been transformed to a pair of time dependent differential equations with variable coefficients. These differential equations are solved using the method given by Sachenkov and Baktieva (1978). Thus, general formulas have been obtained for the dynamic and static critical external pressures and the pertinent wave numbers, critical time, critical pressure impulse and dynamic factor. Finally, carrying out some computations, the effects of the nonhomogeneity, the loading speed, the variation of the semi-vertex angle and the power of time in the external pressure expression on the critical parameters have been studied

The dynamic stability of a laminated nonhomogeneous elastic cylindrical shell

International Conference on Steel Structures of the 2000's -- SEP 11-13, 2000 -- ISTANBUL TECH UNIV, ITU AYAZAGA CAMPUS, ISTANBUL, TURKEYWOS: 000165947900036In this study, the dynamic stability problem of a laminated circular cylindrical shell composed of layers of nonhomogeneous orthotropic elastic materials with elasticity moduli and density varying piecewise continuously in the thickness direction under the effect of an axial compression varying with a power function of time, is considered. At first, the fundamental relations and the dynamic stability equations of a nonhomogeneous orthotropic elastic cylindrical shell with n layers is set up. Applying Sachenkov's method [1], the formulas for the dynamic and static critical loads and the corresponding wave number and dynamic factor are obtained. The results are verified using previous works.Turkish Construct Steelwork Assoc, European Convent Construct Steelwor