NSM CFRP Strengthening and Failure Loading of a Posttensioned Concrete Bridge
Publication: Journal of Composites for Construction
Volume 20, Issue 3
Abstract
Two carbon-fiber-reinforced polymer (CFRP) systems developed as possible means to strengthen existing concrete structures have been applied to a bridge at Kiruna (Sweden). The bridge was no longer in service and was thus used in extensive tests to failure. It was a posttensioned five-span bridge consisting of three longitudinal main girders topped with a concrete slab. The program reported here consisted of a series of three tests of the girders in the second span: loading each girder up to 2.0 MN before strengthening, loading each girder up to 2.0 MN after strengthening, and loading to failure after strengthening. One of the girders was strengthened by installing three near-surface mounted (NSM) CFRP bars on the soffits, and another by installing three prestressed CFRP laminates. This paper focuses on the NSM-strengthened girder, which failed at a maximum load of 6.1 MN, with a corresponding midspan deflection of 159 mm. The failure was a combination of flexure and shear, and the strain in the NSM bars at the ULS was 1.2%.
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Acknowledgments
The authors would like to acknowledge LKAB, Trafikverket, the Hjalmar Lundbohm Research Center, MAINLINE and the Elsa & Sven Thysell Foundation for funding this research project. Complab assisted with the monitoring and Skanska Spännarmering managed the loading.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 20 • Issue 3 • June 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Apr 28, 2015
Accepted: Aug 25, 2015
Published online: Nov 12, 2015
Discussion open until: Apr 12, 2016
Published in print: Jun 1, 2016
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