Uncertainty Analysis of multi-site damage Crack Propagation Based on the Monte Carlo Method

Abstract Widespread fatigue damage is one of the main damages of aging aircraft structures, and the problem of multi-site damage has always been a research hotspot in engineering analysis. The traditional probabilistic model for calculating the growth rate of multiple cracks takes into account the multiple uncertain parameters that affect each other’s cracks. However, when solving the multi-site damage (MSD) crack growth problem, the traditional random model needs to solve multiple nonlinear equations. This method becomes no longer applicable. Based on the statistical point of view, this study gives the mutual influence factors of the crack growth process in the form of distribution, and then calculates the probability density function of the crack length under different cycles by sampling with the Monte Carlo (MC) method. Finally, compared with the experimental data, the results show that the calculation results of this method are more accurate and are in good agreement with the experimental data. This method is feasible and accurate for multi-crack propagation analysis of random parameter structures.