First Ply Failure Study of Laminated Composite Conoidal Shells Using Geometrically Nonlinear Formulation

Abstract

The literature clearly indicates that the failure of laminated composite plates have been studied in detail while composite shell structures have received limited attention. Though few recent papers reported first ply failure of conoidal shells in order to apply these shell forms confidently in industrial applications, the failure investigations need to be continued for different parametric variations keeping the industrial requirements in mind. This study attempts to fill the lacuna. An isoparametric finite element code considering geometrically nonlinear strains and constant shear deformation along the thickness direction of the shell is proposed to study failure initiation in uniformly loaded laminated conoidal shell roofs having two adjacent boundaries simply supported and other two adjacent edges clamped. Moreover, failure locations and modes or tendencies of failure are also reported. The results are studied for varying stacking orders and laminations. This study recommends that the practicing engineers must adopt 30°/−30°/30° laminate to maximize load-carrying capacity of the shell for the edge condition taken up here.