Performance indices for arbitrarily scaled rectangular cross-sections in bending stiffness design

Abstract

Performance indices are presented for the selection of optimal rectangular beams in bending stiffness design. Previous studies have developed performance indices for only three design cases: proportional scaling of width and height, constrained height and constrained width. This paper extends the methodology of the performance index to any arbitrary direction of scaling. The performance index has the form E^q/p, where q is a function only of the scaling vector between two cross-sectional envelopes of different materials. The paper also presents a graphical method for determining the performance of rectangular beams in stiffness design. The perormance index and the graphical method are applied to a design case study.

Keywords

performance index arbitrary scaling constrained design optimal selection

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