Wide-bodied transport aircraft are susceptible to the problem of fatigue cracking of the pressurized cabin. In order to design against catastrophic failure due to such fatigue cracking, the residual strength of a transport aircraft fuselage stiffened panel is analyzed for a crack spanning over two bays. A finite element model of the entire fuselage structure of a transport aircraft was modeled and a linear elastic stress analysis was carried out to identify the location of maximum tensile stress location susceptible for initiation of a fatigue crack. This is followed by fracture mechanics analysis of a growing crack in the panel to assess its crack arrest capability. Residual strength assessment was carried out for the panel and it was observed that residual strength of stiffened panel decreases with increase in the crack length, As the crack length approaches stiffener location the stiffener will share the maximum load, resulting in higher residual strength in the skin leading to crack arrest. Also, the residual strengths of the skin, stiffener and the rivets are estimated individually to generate panel strength diagram, which demonstrates the crack arresting capability of the stiffened panel.
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