Strengthening of Preloaded RC Beams Using Hybrid Carbon Sheets
Publication: Journal of Composites for Construction
Volume 11, Issue 3
Abstract
Reinforced concrete (RC) beams subject to service loads of 40 or 60% of steel yielding were strengthened using hybrid continuous carbon fiber sheets. The hybrid systems were made of high-strength and high-modulus carbon sheets, and compared with systems using only high-strength carbon. It was found that the use of high-modulus carbon sheets in hybrid systems could increase the yielding load, the flexural stiffness, the postyielding ductility, and reduce the crack opening in concrete. The slope changes on load-deflection curves at steel yielding are not noticeable in hybrid systems. The tensile strains developed in hybrid sheets after the fracture of high-modulus carbon are higher in magnitude and distributed in a larger area, leading to an ultimate carbon fracture with concrete crushing. These unique features are attributed to the high stiffness and low ultimate tensile strain of the high-modulus carbon fibers which stiffen the structures, avoid or delay the fiber-reinforced polymer debonding, and facilitate the deformability during their subsequent breakdown.
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Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 11 • Issue 3 • June 2007
Pages: 299 - 307
Copyright
© 2007 ASCE.
History
Received: Jun 21, 2005
Accepted: May 18, 2006
Published online: Jun 1, 2007
Published in print: Jun 2007
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