VIBRATIONS OF CYLINDRICAL-SHELLS WITH INTERMEDIATE SUPPORTS

This paper is concerned with the free vibrations of circular cylindric al shells with rigid intermediate supports. The simplest form of thin shell theory according to Donnell and the reputed best first order app roximation theory of Sanders are considered. An automated Rayleigh-Rit z method is adopted to evaluate the natural frequencies and the mode s hapes of the structures. A proposed unified set of Ritz functions is u sed to span the displacement fields of various types and combinations of end boundary conditions. Comparison and convergence studies are car ried out to verify and establish the appropriate number of Ritz functi ons to produce results with an acceptable order of accuracy. Shells wi th any number of intermediate supports and any combination of end boun dary conditions can be analyzed by the proposed method. Effects of int ermediate supports and their locations on natural frequencies of the s hells are studied and the results presented for easy access by design engineers. (C) 1995 Academic Press Limited