EFFECTS OF GENERAL LAMINATIONS AND BOUNDARY CONSTRAINTS ON VIBRATION OF COMPOSITE SHALLOW SHELLS

This paper presents a comprehensive parametric study on the essential effects of symmetric and unsymmetric fibre orientations on vibration o f thin, composite double curved (cylindrical, spherical and hyperbolic paraboloidal) shallow shells with arbitrary and complex boundary cons traints. The precise strain and kinetic energy integral expressions fo r the laminates are formulated by using the extremum energy principle with no restrictions on the number of laminations and fibre orientatio ns. A versatile and flexible general method of solution for vibration of composite laminates is developed. Convergence and comparison studie s are reported to verify the consistency and accuracy of this analysis method. New results are presented for simply supported and fully clam ped laminated shells with multiple laminations, symmetric and unsymmet ric stacking sequences for two types of composite materials. The influ ence of fibre angles and stacking sequences on vibration mode shapes i s also illustrated.