MULTI-OBJECTIVE TRUSS STRUCTURAL OPTIMIZATION CONSIDERING SIZE, SHAPE AND TOPOLOGY DESIGN VARIABLES SIMULTANEOUSLY

Resumo

Structural multi-objective optimization problems are common in real-world problems of En-
gineering field where one or more objective functions may be considered and desired to be optimized. In

general, these functions are conflicting, leading to complex optimization problems. This paper analyses
the multi-objective structural optimization problems considering the weight minimization (or volume)

with the compliance or the maximum nodal displacement. The constraints refer to the allowable ax-
ial stresses in the bars. Several experiments are analyzed in this paper, presenting their Pareto-fronts

showing the non-dominated solutions. The structural optimization problems consider sizing, shape, and
topology design variables simultaneously, and they can be continuous, discrete, or mixed. One of the
most important steps, after obtaining the Pareto curve, is the definition of which solution or solutions will
be considered after obtaining the Pareto curve. This task is not trivial, and a Multi-Tournament Decision
method is applied to extract the solutions from the Pareto based on Decision Maker preferences. The
search algorithm adopted here is a modified version of the Differential Evolution called Third Evolution
Step Differential Evolution (GDE3).