Visualizing Search and Solution Spaces in the Optimum Design of Biaxial Columns

Abstract

Optimum detailing of reinforcement bars for biaxial columns is a nontrivial task and there is no guidance in the codes of practice on this issue. Conventional methods of producing a single design solution and the use of optimization methods to find a single global optimum solution is not what practicing engineers require. This paper introduces an innovative approach to design, which emphasizes the interactive use of evolutionary computing in design and a new approach to visualization of search and solution spaces. This replaces the “black box” nature of the optimization techniques with an interactive approach in which the designer is in full control of the process. Instead of locating a single solution, clusters of good designs are identified in color, allowing the designer to conduct a more focused search in the areas of high performance design solutions. This method enables the designer to view individual solutions in the vicinity of the local peaks in order to learn more about the interrelationship between design parameters. Interactive visualization tools enable designers to develop a deeper understanding of the search and solution spaces and assist them in evaluating the merits of alternative designs and in their decision making. A by-product of visualization is knowledge discovery, which allows the designer to discover novel solutions that would not have been possible by conventional means. This approach could be easily extended to any stage of multidisciplinary design, especially to the conceptual stage of the design process. For example, the position of bars within a column is similar to the position of columns in a floor layout optimization problem.