The piezoelectric induced bending and twisting deformation of laminated shallow shells has been presented in this report. A simple and efficient method has been developed for the static analysis of shallow shells under mechanical, thermal, and piezoelectric fields. The governing equations are based on the linear theory of piezoelectricity and the classical thin shallow shell assumptions. Approximate solutions have been obtained using the conventional Ritz analysis for different boundary conditions. Comparisons of degenerate cases with published analytical and experimental results show good agreement. Several cases have been reported here, investigating the effects of material stiffness coupling, shell shallowness, and actuator geometric parameters on the bending and twisting deformation of piezoelectric laminated structures. It is shown that the desired shape could be better controlled by a proper selection of the lay-up configuration and geometric characteristics of the structure such as the thickness, size, and location of the piezoelectric actuators.

No abstract

Free asymmetric vibration of spherical shells with clamped and hinged boundary conditions are analyzed using the finite element method. Element stiffness and consistent mass matrices are derived using the improved shell theory, which takes into account the effects of shear deformation and rotary inertia. Natural frequencies for a wide spectrum of shell geometry ranging from shallow cap to hemispherical shell have been computed and are found to be in close agreement with the available data in the literature.

No abstract

No abstract