A COMPARISON OF SOME THIN SHELL THEORIES USED FOR THE DYNAMIC ANALYSIS OF STIFFENED CYLINDERS

The aim of this article is to compare Donnellʹs, Loveʹs, Sandersʹ and Flüggeʹs thin shell theories in the evaluation of natural frequencies of cylinders stiffened with rings and stringers, whose effect is smeared over the entire surface of the cylinder. It is demonstrated that due to the large increase in bending stiffness related to rings, Donnellʹs theory provides highly inaccurate results with respect to the other three theories. Numerical results related to aluminum and composite stiffened cylinders and a comparison with results obtained with a finite element model of a stiffened cylinder complete the work.