Vector optimization of stiffened plates subjected to axial compression load using the Canadian norm

This paper is concerned with the vector optimization problem of longitudinally stiffened plates subjected to axial compression load. This leads to a non-linear vector optimization problem with a finite number of side-conditions, As an application it is considered the optimal design of such plates where the ultimate buckling load should be maximal and the weight minimal. Among the different formulae and recommendations for the prediction of the ultimate buckling load, the Canadian norm CAN-S136-M89 (1989) was chosen for its simplicity and for producing one of the best results, The chosen design variables are the number, the thickness and the height of the stiffeners, Several constraints are considered, Brosowski and Conci (1983), and constrains avoiding the failure due to the lateral buckling for torsion of the longitudinal stiffeners are introduced considering different norms Falco (1996), These side-conditions created a bounded feasible set of points, The compromise solution of this multi-objective optimization problem is established by an interactive procedure using the Efficient Points Method, developed by Brosowski (1985), which leads the problem, with n objective-functions, to a problem with (n-1) ones. In the particular case of the optimization of stiffened plates, it is used a simplification procedure of scalarization, which consists of the minimization of only one objective-function with only one variable within an established interval. An example is considered illustrating the potentiality of this method for practical cases.