Flexural Resistance of Longitudinally Stiffened I-Girders. II: LTB and FLB Limit States
Publication: Journal of Bridge Engineering
Volume 22, Issue 1
Abstract
The current AASHTO specifications impose a penalty on the strengths corresponding to the compression flange in slender-web cross sections due to bend-buckling of the web in flexural compression. This web bend-buckling factor (Rb) does not account for any potential benefits from the influence of web longitudinal stiffening. In a companion paper, the authors developed a cross-section model that can be used to estimate the flexural capacity of I-girders at the yield limit state. In this paper, an improved handling of combined web bend-buckling and lateral torsional buckling (LTB) of longitudinally stiffened I-girders is proposed based on finite-element test simulations. Results from the proposed prediction model are compared to available experimental tests. In addition, the Rb calculated from the proposed model, used in conjunction with the current specification flange local buckling (FLB) equations, is shown to provide an improved characterization of the FLB capacity of these types of members.
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Acknowledgments
This research was funded by the American Iron and Steel Institute and AASHTO. The financial support from these organizations and the Georgia Institute of Technology is gratefully acknowledged. The opinions, findings, and conclusions expressed in this paper are those of the writers and do not necessarily reflect the views of the aforementioned organizations.
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Published In
Journal of Bridge Engineering
Volume 22 • Issue 1 • January 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Jan 28, 2016
Accepted: Jun 20, 2016
Published online: Aug 26, 2016
Published in print: Jan 1, 2017
Discussion open until: Jan 26, 2017
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