Optimum Design of Trusses with Buckling Constraints
Publication: Journal of Structural Engineering
Volume 111, Issue 7
Abstract
A method is developed for the optimum design of trusses including constraints on tension and compression stresses, displacements and bounds on the design variables. It is intended to solve a practical problem. The method takes into account the efficiencies achieved for simpler mathematical models where the allowable values for compression stresses are constant. In this work, these values depend on the member cross section and are prescribed in the Code AISC‐78. All the peculiarities introduced by the buckling constraints are identified and solved. They are: (1) Consideration of the radius of gyration, in addition to the cross‐sectional area, as design variable; (2) introduction of more complicated constraint functions; and (3) computation of a scale factor to the constraint surface for buckling restrictions. The problem is solved by means of a sequence of approximate problems in the dual space. The approximation is basically due to the fact that the constraint functions are replaced by their first order Taylor series expansions to improve the efficiency of the solution. The effectiveness of the method is shown through some examples.
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Copyright © 1985 ASCE.
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Published online: Jul 1, 1985
Published in print: Jul 1985
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