FREE-VIBRATION OF PRETWISTED, CANTILEVERED COMPOSITE SHALLOW CONICAL SHELLS

The free vibration analysis of composite shallow conical shells, incor porating the effects of pretwist, is presented. The analysis focuses o n shells made of symmetrically and unsymmetrically Laminated E-glass/e poxy with four and eight-ply laminates. This method is valid, however, for any other composite with an arbitrary number of layers and fiber orientation. An extremum energy principle is employed to derive the ei genvalue equation, and a flexible, global admissible function is devel oped to account for the geometric boundary conditions. New vibration f requency parameters and mode shapes are presented.