Automatic Yield-Line Analysis of Practical Slab Configurations via Discontinuity Layout Optimization
Publication: Journal of Structural Engineering
Volume 143, Issue 7
Abstract
The yield-line method provides a powerful means of rapidly estimating the ultimate load that can be carried by a reinforced concrete slab. The method can reveal hidden reserves of strength in existing slabs and can lead to highly economic slabs when used in design. Originally conceived before the widespread availability of computers, the yield-line method subsequently proved difficult to computerize, limiting its appeal in recent years. However, it was recently demonstrated that the discontinuity layout optimization (DLO) procedure could be used to systematically automate the method, and various isotropically reinforced, uniformly loaded slab examples were used to demonstrate this. The main purpose of this paper is to demonstrate that the DLO procedure can also be applied to a wide range of more practical slab problems, for example involving orthotropic reinforcement, internal columns, and point, line, and patch loads. The efficacy of the procedure is demonstrated via application to a variety of example problems from the literature; for all problems considered solutions are presented that improve upon existing numerical solutions. Furthermore, in a number of cases, solutions derived using previously proposed automated yield-line analysis procedures are shown to be highly nonconservative.
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Acknowledgments
Initial work in the area of this study was undertaken while the second author was in receipt of an EPSRC Advanced Research Fellowship, Grant No. GR/S53329/01. The authors wish to thank Charles H. Goodchild from the U.K. Concrete Centre and John Sestak from Powell Tolner & Associates for providing the geometric data required for the analysis of the slab shown in Fig. 18.
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Published In
Journal of Structural Engineering
Volume 143 • Issue 7 • July 2017
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This work is made available under the terms of the Creative Commons Attribution 4.0 International license, http://creativecommons.org/licenses/by/4.0/.
History
Received: Aug 20, 2015
Accepted: Sep 19, 2016
Published ahead of print: Feb 28, 2017
Published online: Mar 1, 2017
Published in print: Jul 1, 2017
Discussion open until: Aug 1, 2017
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