Title:
Torsion Behavior of Concrete Beams Reinforced with Glass Fiber-Reinforced Polymer Bars and Stirrups
Author(s):
Hamdy M. Mohamed and Brahim Benmokrane
Publication:
Structural Journal
Volume:
112
Issue:
5
Appears on pages(s):
543-552
Keywords:
beam; code; design; fiber-reinforced polymer; steel; torsion
DOI:
10.14359/51687824
Date:
9/1/2015
Abstract:
This paper presents the results of an investigation of torsional
strength and behavior of full-scale concrete beams reinforced with glass fiber-reinforced polymer (GFRP) bars and stirrups. The beams measured 4000 mm (157.5 in.) long, 250 mm (9.8 in.) wide, and 600 mm deep (23.6 in.) and were tested under pure torsion loading. The test specimens included four beams reinforced with GFRP bars and stirrups and one control beam reinforced with conventional steel reinforcement. The test variables were the type and ratio of torsional reinforcement. As designed, all specimens failed due to diagonal torsional cracking with GFRP stirrup rupture. The test results indicated that the GFRP-reinforced concrete (RC) beam exhibited similar strength and cracking behavior with lower postpeak torsional stiffness compared to the counterpart steel RC beam. In addition, it was found that the closer the spacing of the GFRP
stirrups, the higher the enhancement of the torsional strength with improvement in the post-peak stiffness. Finally, the paper examines the validity of the new design provisions in CAN/CSA S806-12 in predicting the nominal torsional strength of GFRP RC beams.