Theoretical Study of Strengthening for Increased Shear Bearing Capacity
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Volume 9, Issue 6
Abstract
In recent years, the use of carbon fiber reinforced polymer (CFRP) has been shown to be a competitive method for strengthening both the structural and economic performance of concrete. The method has been used for almost a decade, yet – most research undertaken has studied the flexural behavior of strengthened structures, while research on shear strengthening has been limited. The work presented in this paper focuses on CFRP shear strengthening of concrete beams. The theory presented addresses the limitations of the widely used truss model, and a refinement is suggested. A reduction factor to consider the nonuniform strain distribution over the cross section is proposed and strain limitations are prescribed for the principal strain in the concrete instead of the fiber strain, as in previous studies. The derived analytical model is compared to experimental data from tests. Fairly good agreement is found between results from tests and calculated values from theory with regard to both shear-bearing capacity and average fiber utilization.
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Acknowledgments
Lars-Erik Lundberg’s Foundation, The Swedish Building and Development Fund, and Skanska AB have provided financial support. For help with the laboratory tests, special thanks should be given to Håkan Johansson, Lars Åström, and Georg Danielsson at TESTLAB, Luleå University of Technology. Last but not least, the student Andy Hägglund should be thanked for his never-ending energy working on this project and for fruitful discussions.
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Information
Published In
Journal of Composites for Construction
Volume 9 • Issue 6 • December 2005
Pages: 497 - 506
Copyright
© 2005 ASCE.
History
Received: May 14, 2003
Accepted: Mar 7, 2005
Published online: Dec 1, 2005
Published in print: Dec 2005
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