[01] Sarmila Sahoo, Department of Civil Engineering, Heritage Institute of Technology, Kolkata, India.

Performance characteristics of stiffened composite doubly curved shells with cutout are analyzed in terms of natural frequency. A finite element code is developed for the purpose by combining an eight noded curved shell element with a three noded curved beam element. The code is validated by solving benchmark problems available in the literature and comparing the results. The size of the cutout is varied for different edge constraints of cross-ply and angle-ply laminated composite shells. The results furnished here may be readily used by practicing engineers dealing with stiffened composite conoids, hyperbolic paraboloids and elliptic paraboloids with cutouts.

Laminated Composite, Doubly Curved Shells, Cutout, Fundamental Frequency

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