Safety analysis for large aircraft wing-fuselage joint structure with random uncertainty

Non-linear finite element (FE) methods and reliability techniques are used to determine the safety degree of the large aircraft wing-fuselage joint structure with random uncertainty. The randomness of the basic parameters, such as loadings, physical properties and geometrical parameters are considered in the safety analysis. For the given original basic parameters, the response of the stress-strain in the joint structure can be easily calculated by the standard finite element software, but it is very difficult to get the probability safety degree due to its implicit limit state equation. Two numerical algorithms, response surface method(RSM) and advanced mean value first order method(AMVFOM), are combined with the standard FE software for the reliability analysis of the joint structure. The advantages and disadvantages of these two numerical methods are illustrated by the analysis of the strength reliability, stiffness reliability and hybrid strength-stiffness reliability of the joint structure. The results show that the two numerical algorithms are not time consuming comparing with Monte Carlo Method, and the presented methods are acceptable compromise between the accuracy and the computational effort.