S. Nagendra et al., DERIVATIVE BASED APPROXIMATION FOR PREDICTING THE EFFECT OF CHANGES IN LAMINATE STACKING-SEQUENCE, Structural optimization, 11(3-4), 1996, pp. 235-243
Derivatives of buckling loads of stiffened panels with respect to ply
thicknesses are easy to calculate. Consequently, such derivatives are
often available in computer programs that calculate buckling loads of
composite structures. These derivatives can be used to construct appro
ximations of the dependence of the buckling load on ply thicknesses. T
he present work demonstrates the use of derivatives of buckling loads
with respect to ply thicknesses to approximate the effects of changes
in stacking sequence and ply orientations on buckling load of a lamina
te. Examples of unstiffened and stiffened panels are used to demonstra
te the effectiveness of the proposed approximation.