An efficient reliability method for composite laminates with high-dimensional uncertainty variables

This paper develops an efficient reliability analysis method for composite structures with high-dimensional uncertain variables. The concept and mathematical definition of the approximate design point (ADP) and the approximate important direction (AID) are introduced. A fast calculation ADP/AID formula is proposed. A numerical line sampling (LS) strategy is devised, which is further combined with ADP/AID to form a novel reliability method, named AID-LS. An equivalent criterion is introduced to address the problems with the non-normal random variables. A stochastic mechanical model of composite structures with geometrical nonlinearity is established based on first-order shear deformation theory and implemented with finite element analysis (FEA). Numerical examples are given to demonstrate the validity of the proposed method. The results show that the proposed method can significantly reduce the number of FEA samples in the reliability analysis of composite structures.