Optimization of structures having general cross-sectional relationships using an optimality criterion method

Abstract

An optimality criterion-based method for locating the optimal designs of structures with members having general cross-sectional relationships is presented. The method exploits the concept of one most active constraint to avoid the need of calculating a large set of Lagrange multipliers for the active constraints and also eliminates the need to decide as to whether or not a particular constraint should be considered active. The method also avoids the scaling procedure normally used in other optimality criterion techniques and can deal with multiple load conditions and design-variables linkage. Several example structures, designed under stress, displacement, minimum and maximum area constraints and design-variables linkage are presented. The results demonstrate the simplicity, efficiency and reliability of the method even when used on small microcomputers. Although this research is based on the concept of one most active constraint, several constraints may be active at the optimal designs.