This article presents a methodology for optimizing the shape of thin-walled
structures having a beam-like dynamic behavior. The equivalent nominal bea
m characteristics (quadratic moments of inertia, torsional rigidity, etc.)
of a refined finite element model are determined from a direct calculation
based on explicit equations which are functions of the nodal coordinates de
fining the cross-sectional geometry. A subset of these coordinates is then
taken as the design variables for a nonlinear optimization problem where ne
w target physical properties are sought. A complementary model reduction pr
ocedure is introduced to improve the precision of the proposed method for b
eams with variable cross-section or topological accidents. (C) 2001 Elsevie
r Science Ltd. All rights reserved.