Nonlinear First Ply Failure Study on Clamped Composite Cylindrical Shells Under Sinusoidal Load

Composite materials are replacing the conventional ones in various structural engineering applications due to their high strength-to-weight and high stiffness-to-weight ratios. Failure in laminated composites starts with the failure of the weakest lamina and may propagate and lead to catastrophic failure of the structural element if the failure is unnoticed. So, the designer must be aware of the failure load carrying capacities of the laminated composite structural elements to arrive at a safe and economic design. Among the various composite shell geometries, the cylindrical shell panel has wide industrial applications but the first ply failure study on these structural units is far from complete. This shell configuration has also not received any attention from the researchers related to failure behaviour under nonuniform loadings like snow load which is often encountered in cold climate regions. Realising this aspect, the present research aims to study the nonlinear first ply failure characteristics of laminated composite cylindrical shell panels of clamped edges under sinusoidal load. The present finite element approach utilises the Sanders’ strains for thin shell together with the von-Kármán nonlinear strain components. An eight noded curved quadratic isoparametric finite element having five degrees of freedom at each node is used in the present study. The results will be presented systematically for lucid understanding and will be interpreted from practical engineering angles.