Prager‐Shield Optimality Criteria for Linear Segmentation
Publication: Journal of Engineering Mechanics
Volume 115, Issue 1
Abstract
Static-kinematic optimality criteria are introduced for plastically designed structures having segments of prescribed length such that the variation of the cross sectional area is (1) Segmentwise linear; and (2) continuous across segment boundaries. It is shown that, compared to other geometrical constraints suggested in the past, these constraints have the following advantages: (1) Stress concentrations due to cross-sectional discontinuities are avoided; (2) unlike some unconstrained optimal solutions, the underlying assumptions of simple structural theories are not violated; and (3) a high degree of design flexibility, an easier fabrication (due to linear segments), and a greater material economy are achieved. The optimality criteria, which turn out to be similar to those of Foulkes, are derived in a general form and then they are applied to a clamped beam with four segments. This theory is being extended to (1) Elastic design; and (2) other types of structures (e.g., plates).
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 115 • Issue 1 • January 1989
Pages: 203 - 209
Copyright
Copyright © 1989 ASCE.
History
Published online: Jan 1, 1989
Published in print: Jan 1989
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