Some Studies on Composite Stiffened Skewed Hypars Under Free Vibration

Abstract

The skewed hypar shells are architecturally beautiful, easy to cast and are often preferred as roofing units. In the present study the literature on composite stiffened panel is studied and it is found that the free vibrations of composite stiffened hypar shell panels have not been studied in details. A finite element is developed combining a composite eight noded shell element with a three noded composite beam element. The code is validated by solving benchmark problems and fundamental frequencies are obtained for different combinations of laminations, boundary conditions and stiffener arrangements (both number and depth). Results are analysed thoroughly and the paper ends with a number of conclusions of design significance.