Probabilistic failure analysis of laminated sandwich shells based on higher order zigzag theory

The probabilistic failure analysis of laminated composite and sandwich shells is studied first time by using an efficient C ₀ 2D finite element model based on higher order zigzag theory incorporating all three radii of curvatures. The proposed model satisfies transverse shear stress continuity at each layer interface besides higher order theory features, hence predicts better transverse shear stresses. The present 2D finite element model predicts failure loads close to 3D elasticity solutions. The model can not only analyze normal curvature shells like cylindrical but also cross curvature shells like hypar shells. Elastic moduli and ultimate strength values are considered as basic random variables. The present study is to find probability of failure of composite/sandwich hypar and cylindrical shells using Monte Carlo simulation and response surface method. The study reveals that Monte Carlo simulation takes 18,500 finite element simulations for one composite/sandwich shell problem whereas RSM takes only 168 finite element simulations to achieve the same accuracy.