Parameter Inversion for Composite Interlayer Cohesive Zone Model Based on Bayesian Inference

Due to the advantages of high specific strength, high specific stiffness and high designability, composites have been widely used in aerospace and other fields, and their main damage mode is delamination damage. Cohesive zone model（CZM） is widely used in design and analysis of composite structures due to its capacity of simulating delamination damage, thus it is very important to accurately determine the parameters of CZM to increase the reliability of the numerical results. The load-displacement data is obtained through the composite double cantilever beam（DCB） experiments. Combined with the corresponding finite element model,Bayesian inference is employed to inversely determine the probability distributions of the parameters for bilinear and exponential CZMs, respectively. Numerical simulation and experimental results have demonstrated that, the two CZMs have neglected effect on the identification of fracture toughness but important effect on the identification of interface strength; since Bayesian inference considers uncertainties from modeling error and measurement noise, compared to deterministic methods, it can obtain more information about the CZM parameters, providing a new method to identify parameters of CZM and perform uncertainty analysis on the results.