Novel Design Algorithms for Factor Calculation and Beam‐Column Selection
Publication: Journal of Structural Engineering
Volume 119, Issue 12
Abstract
Existing methods for calculating the LRFD design nomograph for an effective length factor utilize iterative algorithms such as the method of bisection. This paper presents a novel algorithm that computes the factor with no iterations. This algorithm computes an approximate factor, which is often within 2% of the true nomograph value of . The initial section selection method offered in the LRFD Manual is primarily a hand‐calculation technique relying on the engineer's intuition for selection trial sections. A computer‐based algorithm is developed herein for the initial beam‐column section selection using the LRFD strength criteria (the beam‐column interaction equation). An example problem presents typical preliminary member sizes for girders and beam‐columns using these techniques. The computer program DFRAME, which uses these methods, is briefly described and is implemented in C++, an object‐oriented language, using Digital Equipment and Sun workstations.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 119 • Issue 12 • December 1993
Pages: 3630 - 3648
Copyright
Copyright © 1993 American Society of Civil Engineers.
History
Received: Sep 27, 1991
Published online: Dec 1, 1993
Published in print: Dec 1993
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