Laminated Composite Hyper Shell Roofs With Stiffeners: Free Vibration Behavior Under Different Boundary Conditions

Abstract

An eight noded shell element combined with a three noded beam element is used to study the free vibration behaviour of laminated composite stiffened hypar shells. Benchmark problems are solved to validate the proposed approach and a variety of author’s own problems are solved taking simply supported and clamped boundary conditions. Different types of laminations including symmetric and antisymmetric, cross and angle ply laminations and sixteen combination of stiffening schemes are considered for the present study. The fundamental frequencies obtained for different combinations of laminations, boundary conditions and stiffening schemed are discussed critically.