Fracture Analysis for Damaged Aircraft Fuselage Using Substructure Method

This paper primarily describes the development and application of substructure computational analysis techniques to determine stress intensity factors for the damaged panels subjected to fatigue internal pressure. A program based on substructure analysis technique has been developed for the fracture analysis of curved aircraft panels containing cracks. This program may create whole model which consists of substructure superelements and obtain fracture parameter of the crack by expanding results in superelement automatically. For instance, a typical test curved panel model consists of 7 frames and 8 stringers is calculated. This numerical approach has been validated through comparison between the calculation SIF results and available experimental data of a typical test panel with a longitudinal crack. The technique that has been established here is also applied to the other analysis of a test series of cracked panel with 7 frames and 10 stringers. SIFs of four cracks in it with different crack lengths are obtained efficiently.