* Unit of Mechanics, Modelling and Manufacturing, Tunisia
**University of Technology, Compiegne, France
Département de Technologie, Institut Préparatoire aux Etudes
d’Ingénieurs de Sfax, Route de Menzel Chaker Km 0,5 BP 805
3018 Sfax Tunisia.
This work deals with optimum design of isotropic or composite beams and shell structures with geometrical non-linearities (large displacements and rotations analysis). Suspension parts such as leaf springs are practical applications in the car industry. The thickness distribution is designed to minimize the stresses with a prescribed stiffness for a given load level. An Updated Corotational Lagrangian Formulation is considered for the non-linear analysis with large displacements and rotations but small elastic strains. A mathematical programming technique is coupled with the non-linear analysis code to design 2D and 3D leaf springs.