Analysis of residual strength of stiffened panels with multiple site damage

Multiple Site Damage (MSD) is a typical problem for ageing civil and transport aircraft, where the large number of fuselage pressure cycles may cause fatigue cracking at multiple rivet locations. The residual strength of a panel with a leading crack and MSD cracks is lower than that of a panel with the same leading crack but without MSD. This paper presents an advanced engineering model to predict link-up and the residual strength in flat unstiffened and stiffened panels with one leading crack and MSD cracks. The model is verified using experimental data from the open literature: the predictions are in good agreement with the measured residual strengths.