Shear Strength of Normal Strength Concrete Beams Reinforced with Deformed GFRP Bars.

This paper evaluates the shear strength, Vc, of intermediate length (2.5 < a/d < 6) simply supported concrete beams subjected to four-point monotonic loading and reinforced with deformed, glass fiber-reinforced polymer (GFRP) reinforcement bars. Six different overreinforced GFRP designs, r > rb, were tested with three replicate beams per design. All samples failed as a result of diagonal-tension shear. Measured shear strengths at failure are compared with theoretical predictions calculated according to traditional steel-reinforced concrete procedures and recently published expressions intended for beams reinforced with GFRP. Recommendations are made regarding the adequacy of shear strength prediction equations for GFRP-reinforced members. The study concludes that shear capacity is significantly overestimated by the ‘‘Building Code Requirements for Structural Concrete and Commentary’’ (ACI 318-99) expression for, Vc, as a result of the large crack widths, small compression block, and reduced dowel action in GFRP-reinforced flexural members. Shear strength was found to be independent of the amount of longitudinal GFRP reinforcement. A simplified empirical equation for predicting the ultimate shear strength of concrete beams reinforced with GFRP is endorsed.

Main Author: Yost, Joseph R.
Other Authors: Gross, Shawn P., Dinehart, David W.
Language: English
Published: 2001
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