ABSTRACT
Mathematical formulation of optimum design in engineering is usually written as
minF(A') (1.1) subject to
gj(X)^0 i = l , . . . , m (1.2) In this expression
X is the vector of problem variables F{X) is the objective function gj(X) are the set of problem constraints
In structural optimization (Schmit, 1960) the most usual design variables are mechanical parameters of structure elements, size of cross section internal components or coordinates of nodes which define the structure. The objective function F(X) is generally the structural weight, but more complicated functions are chosen in some problems. The constraints gj{X) represent state variables of structural response for each loading case: stresses, internal forces, displacements, natural frequencies or buckling loads.
