Experimental Investigation on Bond Stress Behavior of Sand-Coated GFRP Bars with Concrete

Zana M. Qader; Feirusha S. M. Kakshar

doi:10.21271/ZJPAS.35.3.3

Authors

Zana M. Qader Department of Civil Engineering, College of Engineering, Salahaddin University-Erbil, Kurdistan-Iraq.
Feirusha S. M. Kakshar Department of Civil Engineering, College of Engineering, Salahaddin University-Erbil, Kurdistan-Iraq.

DOI:

https://doi.org/10.21271/ZJPAS.35.3.3

Keywords:

Bond stress, Slip, concrete beam, sand coated GFRP

Abstract

In this paper, a comprehensive experimental study was conducted to investigate the bond performance of sand-coated glass fiber reinforced polymer (GFRP) bars embedded in normal concrete with different bar sizes and different embedded regions of concrete beams following the regulation of the Rilem beam. The achieved results are compared to the analytical equations presented by current codes and reputable recent research using the average bond strength and the free end bond stress-slip curves. This study contains the effect of bar size and embedded length on bond stress and slippage of sand-coated GFRP bars. From the data observed, bond stress of 8mm bar size is about 23% higher than 10mm and 16% higher than 12mm bar size for 10D embedded length. The 8mm bar size showed the maximum bond stress of 13.8MPa among all the other specimens while the maximum slip measurement was detected from a 12mm bar size of 1.519mm. Bond stress with beam test showed a higher value by almost twice than those derived from other codes. In general, as the bar size increases the bond stress decreases, and as the embedded length increases the bond stress tends to fall. Similarly, the slip of the bar rises as the embedded length rises. The embedded length of 10D recommended by RILEM 1994 is inadequate for GFRP bars. Finally, GFRP bars show higher bond stress than steel bars by 20%.

References

Achillides, Z., Pilakoutas, K., 2004. Bond behavior of fiber reinforced polymer bars under direct pullout conditions. J. Compos. Constr. 8, 173–181.

Basaran, B., Kalkan, I., 2020. Investigation on variables affecting bond strength between FRP reinforcing bar and concrete by modified hinged beam tests. Compos. Struct. 242, 112185.

Coelho, M.R., Sena-Cruz, J.M., Neves, L.A., 2015. A review on the bond behavior of FRP NSM systems in concrete. Constr. Build. Mater. 93, 1157–1169.

Diab, A.M., Elyamany, H.E., Hussein, M.A., Al Ashy, H.M., 2014. Bond behavior and assessment of design ultimate bond stress of normal and high strength concrete, Alexandria Eng. J 53, 355–371.

Fernandez, I., Herrador, M.F., Marí, A.R., Bairán, J.M., 2016. Structural effects of steel reinforcement corrosion on statically indeterminate reinforced concrete members. Mater. Struct. 49, 4959–4973.

Golafshani, E.M., Rahai, A., Sebt, M.H., 2014. Bond behavior of steel and GFRP bars in self-compacting concrete. Constr. Build. Mater. 61, 230–240.

Hasan Sahan Arel and Semsi Yazici, 2014. Effect of Different Parameters on Concrete-Bar Bond under High Temperature. ACI Mater. J. 111. https://doi.org/10.14359/51686992

Kotynia, R., Szczech, D., Kaszubska, M., 2017. Bond behavior of GRFP bars to concrete in beam test. Procedia Eng. 193, 401–408.

Lee, J.Y., Yi, C.K., Cheong, Y.G., Kim, B.I., 2012. Bond stress–slip behaviour of two common GFRP rebar types with pullout failure. Mag. Concr. Res. 64, 575–591.

Lin, X., Zhang, Y., 2014. Evaluation of bond stress-slip models for FRP reinforcing bars in concrete. Compos. Struct. 107, 131–141.

Maranan, G. B., Manalo, A. C., Karunasena, W., & Benmokrane, B. (2015). Pullout behaviour of GFRP bars with anchor head in geopolymer concrete. Composite Structures, 132, 1113-1121.

Mias, C., Torres, L., Turon, A., Sharaky, I., 2013. Effect of material properties on long-term deflections of GFRP reinforced concrete beams. Constr. Build. Mater. 41, 99–108.

Okelo, R., Yuan, R.L., 2005. Bond strength of fiber reinforced polymer rebars in normal strength concrete. J. Compos. Constr. 9, 203–213.

Reichenbach, S., Preinstorfer, P., Hammerl, M., Kromoser, B., 2021. A review on embedded fibre-reinforced polymer reinforcement in structural concrete in Europe. Constr. Build. Mater. 307, 124946.

Rolland, A., Argoul, P., Benzarti, K., Quiertant, M., Chataigner, S., Khadour, A., 2020. Analytical and numerical modeling of the bond behavior between FRP reinforcing bars and concrete. Constr. Build. Mater. 231, 117160.

Solyom, S., Balázs, G.L., 2020. Bond of FRP bars with different surface characteristics. Constr. Build. Mater. 264, 119839.

Tekle, B.H., Cui, Y., Khennane, A., 2020. Bond properties of steel and sand-coated GFRP bars in Alkali activated cement concrete. Struct. Eng. Mech. Intl J. 75, 123–131.