Title:
Assessment of the Existing Shear Resistance Models for RC Beams Strengthened with Near Surface-Mounted FRP Reinforcement
Author(s):
Amirhossein Mohammadi, Joaquim A.O. Barros, José Sena-Cruz, and Salvador J.E. Dias
Publication:
Symposium Paper
Volume:
360
Issue:
Appears on pages(s):
179-193
Keywords:
Analytical models, Shear strengthening, Reinforced concrete (RC), Beams, Near-surface mounted (NSM), Fibre-reinforced polymer (FRP)
DOI:
10.14359/51740624
Date:
3/1/2024
Abstract:
The near surface-mounted (NSM) technique utilizing fibre-reinforced polymer (FRP) reinforcements has gained significant popularity in enhancing the shear resistance of reinforced concrete (RC) beams. Various models have been proposed to predict the shear contribution of NSM FRP reinforcement in RC beams. In this study, the performance of five well-established models, namely those proposed by De Lorenzis and Nanni, Rizzo and De Lorenzis, Dias and Barros, Bianco et al., and Mofidi et al., is assessed. A comprehensive database comprising 137 beams from published works is compiled for this assessment. The findings reveal that the model proposed by Bianco et al. exhibits superior predictive performance but tends to produce extremely conservative predictions. On the other hand, the model proposed by Dias and Barros performs well for beams shear strengthened with FRP laminates, although it is not specifically calibrated for specimens shear strengthened with FRP rods. Notably, the latter model results within an appropriate safety domain, avoiding extreme conservatism. Further research is warranted to develop a comprehensive model with enhanced predictive accuracy.
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