Simplified Method for Calculating Lateral Distribution Factors for Live Load Shear
Publication: Journal of Bridge Engineering
Volume 10, Issue 5
Abstract
The simplified equal distribution factor (EDF) method for live load shear presented in this study originates from Henry’s method, a method that has been used in Tennessee for nearly forty years. Henry’s method allows for equal distribution of live load effects in all beams. This study focused on a careful examination and modification of Henry’s method by comparing shear distribution factors obtained from Henry’s method with those from finite element analysis and other code-specified methods for actual bridges. Twenty-four Tennessee bridges with six different types of superstructures were used in the study. The effects of structural parameters on the shear distribution factors were also studied. Modification factors to Henry’s method were proposed based on the comparison study. The proposed modification factors include structure type factors that are applied to different types of superstructures and a skew correction factor that is used to account for the effects of skew angle for skewed bridges. With proper modifications, the simplified EDF method can produce very reasonable and reliable distribution factors for live load shear.
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Acknowledgments
The writers wish to gratefully acknowledge the financial support of the Tennessee Department of Transportation on this research. Particularly, the writers would like to thank Mr. Mitch Hiles at the TDOT for his advice and assistance. Thanks also go to graduate assistants Stewart Conner, Michael Patrick, and Pingsheng Zhu, who provided assistance during the study. The writers gratefully acknowledge the support of the Center for Electric Power at Tennessee Technological University.
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Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 10 • Issue 5 • September 2005
Pages: 544 - 554
Copyright
© 2005 ASCE.
History
Received: Oct 2, 2003
Accepted: Sep 16, 2004
Published online: Sep 1, 2005
Published in print: Sep 2005
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