Integrally forming stiffeners in a panel provides an economically favorable means of manufacturing stiffened composite panels for use in aerospace structures. How ever, the initial curvature that is introduced into the flat panel region between the stiffeners can significantly reduce the panel's resistance to buckling. The influence of initial curva ture on buckling due to uniaxial compression and to uniform shear is investigated. Finite element analysis is used to predict the initial curvature, and analytical results are used in compensation of the forming tool to reduce the initial curvature. Predictions are compared with experimental buckling results for panels fabricated using the compensated tool.
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