Introduction
Genetic algorithms (GA) have evolved over the last three
decades to be recognized as a very powerful tool in obtaining
solutions to nonengineering and engineering design
optimization problems. The simple GA, while powerful,
is perhaps too general to be efficient and robust
for structural design problems. First, function (or fitness)
evaluations are computationally expensive because
they typically involve finite element analysis. Second, the
(feasible) design space is at times disjointed with multiple
local minima. Third, the design space can be a function
of boolean, discrete and continuous design variables. The