Live Load Testing of NEXT-D Bridges to Determine Distribution Factors for Moment
Publication: Journal of Performance of Constructed Facilities
Volume 34, Issue 4
Abstract
Live load tests were conducted on an in-service bridge containing decked Northeast Extreme Tee (NEXT-D) girders. The purpose of the tests was to evaluate transverse load distribution and to determine which (if any) of the AASHTO LRFD standard bridge sections should be considered when calculating moment distribution factors (DFM). The NEXT-D girders in the test bridge span 12.2 m (40 ft) and utilize ultrahigh performance concrete as the girder shear key fill. The live load tests consisted of crawling () loaded dump trucks at several critical transverse locations across the bridge while simultaneously measuring bending strain in the girders. From this data, experimental interior and exterior girder DFMs were calculated for both one and two lane loads. Based on comparison with the experimental DFMs, it is recommended that the AASHTO LRFD type-k standard bridge section be used when calculating design moment distribution factors for NEXT-D girders.
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Data Availability Statement
All data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
Testing and analysis were sponsored by SCDOT, the Federal Highway Administration, and Clemson University’s Glenn Department of Civil Engineering. Also, thank you to Scott Black, Sachin Sreedhara, and Carter Wertz for helping with the live load test setup.
References
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Published In
Journal of Performance of Constructed Facilities
Volume 34 • Issue 4 • August 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Feb 21, 2019
Accepted: Dec 30, 2019
Published online: May 11, 2020
Published in print: Aug 1, 2020
Discussion open until: Oct 11, 2020
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