Title:
Bond Strength of Nonmetallic Reinforcing Bars
Author(s):
Christopher P. Mosley, A. Koray Tureyen, and Robert J. Frosch
Publication:
Structural Journal
Volume:
105
Issue:
5
Appears on pages(s):
634-642
Keywords:
aramid; bond strength; crack widths; development length; fiber-reinforced polymers; reinforced concrete; splice length
DOI:
10.14359/19947
Date:
9/1/2008
Abstract:
The corrosion of steel reinforcement in reinforced concrete has proved to be a serious detriment to the service life of structures. Whereas there are a multitude of methods that have been employed to minimize the risk of corrosion, the use of nonmetallic or fiberreinforced polymer (FRP) reinforcement eliminates it. Due to the fact that FRP reinforcement has different properties than steel, structures reinforced with FRP reinforcement behave differently. Therefore, many of the design equations used for steel-reinforced concrete structures are not applicable for use with FRP reinforcement. The bond behavior of FRP-reinforced concrete is of particular interest and is the focus of this study. Three series of beam splice tests were performed on specimens reinforced with steel, glass FRP (GFRP), and aramid FRP (AFRP). The test results are compared to evaluate the influence of the reinforcement type, development length, and reinforcement spacing. Furthermore, the test results are compared with current design expressions provided by ACI Committees 318 and 440 to evaluate their applicability. The results of this study demonstrate that the bond strength achieved by FRP reinforcement is significantly lower than that achieved by steel reinforcement and that the reinforcement modulus of elasticity is an essential variable affecting bond strength.