Abstract
There are a large number of inequality constraints in a structural optimum design problem, however, an optimum design point is usually located on active constraint surfaces that are equivalent to equality constraint. If we select such equality constraints among the inequality constraints, the inequality constrained problem can be transformed into an equality constrained problem. An optimum point of the new problem that is subjected to the selected equality constraints is obtained by using the Lagrange multiplier technique. In this paper an optimization method in which selection techniques are used is proposed, and a simple example on optimum solutions of composite plate girders is shown.
