Numerical Study on Failure of Thin Composite Conoidal Shell Roofs Considering Geometric Nonlinearity

Thin laminated composite conoidal shell roofs are popular among civil engineers due to its stiff, singly ruled and aesthetically appealing geometry. Such surfaces may undergo large displacements under transverse static overloading. Since no researchers reported failure of laminated conoids using nonlinear strains the authors aim to fill the void in the literature. A finite element code is proposed considering von-Karman nonlinearity. The study of linear and nonlinear failure loads clearly indicates that the linear formulation wrongly overestimates the failure loads and hence, not acceptable from practical engineering standpoint. Moreover, displacements at failure, the coordinate locations from where the failure initiates and the lamina stress initiating failure in the shell are also studied.