Title:
Analytical Load-Deflection Behavior of Prestressed Concrete Girders Strengthened with FRP
Author(s):
Kimberly Waggle Kramer and Hayder A. Rasheed
Publication:
Symposium Paper
Volume:
327
Issue:
Appears on pages(s):
13.1-13.20
Keywords:
Externally bonded CFRP, Prestressed Concrete Girders, Deflection, Moment-Curvature
DOI:
10.14359/51713334
Date:
11/1/2018
Abstract:
Strengthening of concrete members with external fiber-reinforced polymer (FRP) has become a common practice to in the consulting engineering industry. The deflection of reinforced concrete beams strengthened with FRP is well studied. Conversely, limited studies are available to address the deflection analysis of prestressed reinforced concrete (PRC) beams strengthened with FRP. Nonlinear sectional analysis, simplified by implementing a trilinear moment-curvature response, is used in this paper to obtain closed form analytical deflection expressions for simply supported girders subjected to different loading conditions. The complete load-deflection response of PRC and PRC-FRP beams studied in this paper are generated using the presented procedure and compared to their testing results. To establish the accuracy of the trilinear approach, the analytically assumed moment-curvature predictions were compared to the test results performed by Larson, Peterman, and Rasheed (2005) on T-girders. To verify this response, a fully nonlinear analysis of the same T-girders strengthened with CFRP are performed. A comparison between the analytical and numerical moment-curvature responses are made and presented. The comparison indicates the high accuracy of the analytically assumed moment-curvature function, which represents the foundation for establishing the short-term deflection expressions. The proposed method produced accurate predictions for moment-curvature and short term load-deflection responses of PRC flexural members with straight strands and a T-cross section strengthened with externally bonded FRP. As such, this method shows high promise for establishing short-term deflection expressions that can be universally used in a variety of applications.
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