Comparative Flexural Performance of HSC and NSC One-Way Slabs Reinforced with GFRP and Steel Bars under Three-Point Loading
Ahmed Abdallah Altayeb
Department of Civil Engineering, College of Engineering, University of Bahri, Khartoum, Sudan and Civil Engineering Department, College of Engineering, University of Sinnar, Sinnar, Sudan.
Salih Alhadi Mohamed Ahmed
Department of Civil Engineering, College of Engineering, University of Bahri, Khartoum, Sudan.
Bashir H. Osman *
Civil Engineering Department, College of Engineering, University of Sinnar, Sinnar, Sudan.
Eltayeb Abdellatif Ahmed Habib
Department of Civil Engineering, College of Engineering, University of Bahri, Khartoum, Sudan.
*Author to whom correspondence should be addressed.
Abstract
The flexural behavior of simply supported one-way slabs constructed with high-strength concrete (HSC) and normal-strength concrete (NSC) and reinforced with glass fiber reinforced polymer (GFRP) bars, was investigated experimentally with different pf/pfb ratios. The ultimate load capacity, crack patterns, failure modes, ultimate deflection, and concrete and GFRP steel bar strains, are considered as main parameters. Four large-scale reinforced concrete slabs were compared under three-point load. Results showed that slabs reinforced with GFRP bars in both NSC and HSC exhibited higher deflections at each load increment compared to steel- reinforced slabs and recorded less ultimate load, compared to control slabs. Furthermore, GFRP reinforced slab failed by GFRP rupture and bond failure without any warning and showed large cracks compared to that reinforced with normal steel. Moreover, the experimental results align with analytical results from several codes. The predicted and experimental moments at cracking and ultimate loads aligned well for under-reinforced slabs, whereas the results for the over-reinforced GFRP slabs were slightly un conservative, also CSA S806 2012 showed a good agreement for a comparison between predicted and experimental mid-span deflection. The EURO EN 1992-1-1:2004 shows reasonable agreement with experimental cracks width results compared with other codes with error band not more than 10%.
Keywords: GFRP, Slab, flexural behaviors, HSC, failure modes