GA topology optimization using random keys for tree encoding of structures

  • J. F. Aguilar Madeira
  • H. L. Pina
  • H. C. Rodrigues


Topology optimization consists in finding the spatial distribution of a given total volume of material for the resulting structure to have some optimal property, for instance, maximization of structural stiffness or maximization of the fundamental eigenfrequency. In this paper a Genetic Algorithm (GA) employing a representation method based on trees is developed to generate initial feasible individuals that remain feasible upon crossover and mutation and as such do not require any repairing operator to ensure feasibility. Several application examples are studied involving the topology optimization of structures where the objective functions is the maximization of the stiffness and the maximization of the first and the second eigenfrequencies of a plate, all cases having a prescribed material volume constraint.


Structural topology design Eigenfrequency design Optimization Genetic algorithms Graph theory 


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • J. F. Aguilar Madeira
    • 1
    • 2
  • H. L. Pina
    • 1
  • H. C. Rodrigues
    • 1
  1. 1.IDMEC - ISTLisbonPortugal
  2. 2.ISEL - Instituto Superior de Engenharia de LisboaLisbonPortugal

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