Development of Live-Load Distribution Factors for Glued-Laminated Timber Girder Bridges
Publication: Journal of Bridge Engineering
Volume 16, Issue 2
Abstract
This paper presents simple relationships for calculating live-load distribution factors for glued-laminated timber girder bridges with glued-laminated timber deck panels. Analytical models were developed using the Ansys 11 finite-element program, and the results were validated using recorded data from four in-service timber bridges. The effects of the bridge span length, the spacing between girders, and the bridge width on the distribution of the live load were investigated by using the validated models. The live-load distribution factors obtained from the field test and the analytical models were compared with those obtained using the AASHTO LRFD Bridge Design Specifications live-load distribution relations. The comparison showed that the live-load distribution factors obtained by using the AASHTO LRFD Bridge Design Specifications were conservative. For this reason, statistical methods were used to develop accurate relationships that can be used to calculate the live-load distribution factors in the design of glued-laminated girder bridges.
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Acknowledgments
The writers would like to express their sincere appreciation to the engineers and staff from the USDA Forest Products Laboratory. Special thanks are extended to Mike Ritter from FPL for his support and technical recommendations for this research. Thanks are also extended to Douglas Wood from Iowa State, who supervised the field testing of the bridges listed in this work.
References
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Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 16 • Issue 2 • March 2011
Pages: 179 - 187
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Nov 25, 2008
Accepted: Mar 29, 2010
Published online: Apr 5, 2010
Published in print: Mar 1, 2011
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