Application of an advanced evolutionary strategy for the automatic design of modular steel structures

Modular three-dimensional steel frames, like steel pallet racks or shelving assemblies and scaffoldings are prefabricated structures with slender elements and dominating compressive forces. The analysis includes different nonlinearities and the optimization variables are often mixed-discrete or topological.The optimization of these systems requires the most advanced solution techniques but also a systematic preprocessing, a sophisticated nonlinear structural analysis and an automated handling of stress- and displacement-constraints as well as further side-constraints resulting from the underlying codes of practice. The objective of the optimization is the minimization of cost. In this contribution a (µ +1)- evolutionary strategy (ES) in combination with an adaptive penalty function and a special selection scheme is presented to solve this optimization problem.Two examples from literature are solved and the results are compared. The examples show the reliability and robustness of the presented method.