Investigation and examples of evalutionary structural optimization

ABSTRACTMaster ThesisINVESTIGATION AND EXAMPLES OF EVALUTIONARY STRUCTURAL OPTIMIZATIONÖmer Faruk USLUOĞULLARIFırat UniversityGraduate School of Science and TechnologyDepartment of Civil Engineering2005, Page: 61In this study steps of optimization methods and the concepts which can be come across inthese steps (design variables, constraints, objective functions, several optimization methods, etc.) werestudied. After then, as a new optimization method, Evolutionary Structural Optimization (ESO) will beintroduced. The objective of Evolutionary Structural Optimization is same with other optimizationmethods namely it want to get uniform designs where all the elements on structures or at the surface ofstructures are at the same stress level.In the ESO method ANSYS program was used and the analyses were carried out by finiteelement methods. Results were determined by using computer-aided programs with after using theseresults to remove ineffective elements simple ESO methods was used. With ESO method iterativeanalysis were carried out to remove elements. After all individual analysis was completed, ineffectiveelements removed gradually from system and result of this removal process optimum structure wasacquired. To make comparison with this method the optimization module of ANSYS program wasused.Systems which will be transformed into frames with two bars and Michell beams wereprepared as numerical examples. The systems used in the examples were designed by ANSYSprogram and structural analysis was carried out with macros added to algorithm of ANSYS program.Generally optimization processes contain complex mathematical formulations and equations.However, it can be seen in the examples that ESO method has steps which are, understandable, easilyapplied and aware of complexity.Keywords: ANSYS, Optimization, Evolutionary Structural Optimization, Structural Design