Uniaxial Tensile Stress-Strain Relationships of RC Elements Strengthened with FRP Sheets
Publication: Journal of Composites for Construction
Volume 20, Issue 3
Abstract
The shear behavior of fiber-reinforced-polymer–strengthened reinforced concrete (FRP-strengthened RC) members is not fully developed and accurately predicted because of the lack of accurate constitutive laws for the components of the composite members. This paper presents experimental and analytical investigations of tensile stress-strain relationships of concrete and steel in FRP-strengthened RC members. These stress-strain relationships are required in formulations of softened truss models to predict the shear behavior of the FRP-strengthened RC element. Thirteen full-scale FRP-strengthened RC prismatic specimens with different FRP reinforcement ratios, steel reinforcement ratios, and FRP wrapping schemes were tested under uniaxial tension loading. The results show that the tensile behavior of the concrete and steel is altered because of the externally bonded FRP sheets. Modified constitutive laws are proposed and incorporated in the softened membrane model (SMM) to demonstrate through two tests the behavior of FRP-strengthened RC element subjected to pure shear. Moreover, crack spacing and crack width were studied and compared with existing code provisions.
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Acknowledgments
This research is supported by the National Science Foundation, award number 1100930. Steel reinforcements and FRP materials were donated by GERDAU AMERISTEEL Co. (Navasota, Texas) and FYFE. Co. (San Diego, California), respectively. Their support is greatly acknowledged.
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Journal of Composites for Construction
Volume 20 • Issue 3 • June 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Mar 2, 2015
Accepted: Sep 14, 2015
Published online: Nov 5, 2015
Discussion open until: Apr 5, 2016
Published in print: Jun 1, 2016
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