Probabilistic failure prediction in a double composite cantilever beam with single and double source uncertainty

Abstract

Predicting failure in composite materials under service loading conditions has been challenging due to the non-uniform mechanical properties arising from the composite fabrication process. Including these uncertainties in the analysis becomes critical. The probabilistic approach plays a vital role in making the design less conservative and anticipates the risk associated with the design incorporating the uncertainties. In this work, metamodels such as support vector machines, radial basis function, and logistic regression in conjunction with Latin hypercube, Sobol, and Halton sequence sampling methods were used to calculate the failure probability in the carbon fibre/epoxy-based composite material. Here, the composite plates were fabricated using the vacuum-assisted resin transfer molding (VARTM) process. The variation in the fibre-volume fraction was evaluated at different sites of the composite plate. Then, the effective orthotropic properties of the composite for various fibre-volume fractions have been numerically computed by the homogenisation method using periodic boundary conditions. A double cantilever composite beam problem was considered to predict the failure probability by including the uncertainties in single-source — fibre-volume fraction and double-source — fibre-volume fraction and fracture toughness. At the end, a study to ascertain the metamodels stability was presented to demonstrate the accuracy and effectiveness of the proposed approach.