Effect of chloride content on bond behavior between FRP and concrete

Abstract

For reinforced concrete structures located along the seaside, the penetration of chloride ions into concrete may be a threat to the durability of the structures. Experimental investigations were carried out to study the effect of chloride content on the bond behavior between concrete and fiber reinforced polymer (FRP) plates. Direct shear tests were conducted on the FRP strengthened concrete members. Before testing, the specimens were immersed in NaCl solutions with concentrations ranging from 3%–15% for different time (0–120 d). Then, the specimens were dried and tested to obtain the initial and ultimate debonding loads, together with strain distributions along the FRP plates of different load values. The correlations between chloride content and debonding parameters are established. Test results show that the debonding parameters are closely related to the immersing time rather than the chloride content of the solution.

Keywords

fiber reinforced polymer (FRP) / concrete / chloride content / direct shear test / debonding behavior

References

[1] Meier U., Deuring M., Meier H., et al. Strengthening of structures with CFRP laminates: Research and applications in Switzerland[J]. Advanced Composite Materials in Bridges and Structures, 1992, 58(3): 33-77.

[2] Ritchie P. A., Thomas D. A., Lu L. W., et al. External strengthening of concrete beams using fiber-reinforced plastics[J]. ACI Struct J, 1991, 88 490-500.

[3] Saadatmanesh H., Ehsani M. R. RC beams strengthened with GFRP plates (I): Experimental study[J]. J Struct Eng, 1991, 117(11): 3417-3433.

[4] Almusallam A. A., Al-Gahtani A. S., Rasheeduzzafar A. R. Effect of reinforcement corrosion on bond strength[J]. Construction and Building Materials, 1996, 10(2): 123-129.

[5] Al-Sulaimani G. J., Kaleemullah M., Basunbul I. A., et al. Influence of corrosion and cracking on bond behaviour and strength of reinforced concrete members[J]. ACI Structural Journal, 1990, 87(2): 220-231.

[6] Cabrera J. G. Deterioration of concrete due to reinforcement steel corrosion[J]. Cement and Concrete Composites, 1996, 18(1): 47-59.

[7] Teng J G, Chen J F, Smith S. FRP-Strengthened RC Structures [M]. John Wiley and Sons, Ltd, 2001.

[8] Arduini M., Di Tommaso A., Nanni Antono. Brittle failure in FRP plate and sheet bonded beams[J]. ACI Structural Journal, 1997, 94(4): 363-370.

[9] Norris T., Saadatmanesh H., Ehsani M. R. Shear and flexural strengthening of RC beams with carbon fiber sheets[J]. Journal of Structural Engineering, ASCE, 1997, 123(7): 903-911.

[10] EI Maaddawy T., Chahrour A., Soudki Khaled. Effect of fiber-reinforced ploymer wraps on corrosion activity and concrete cracking in chloride-contaminated concrete cylinders[J]. Journal of Composites for Construction, ASCE, 2006, 10(2): 139-147.

[11] Craig B C, Soudki K A. Confining effects of CFRP laminates on corroded concrete members [C]. In: Brahim Benmokrane, Proceedings of the 2nd International Conference (CDCC’02). Montreal, Canada, 2002. 383–394.

[12] Masoud S., Soudki K., Topper Tim. CFRPstrengthened and corroded RC beams under monotonic and fatigue loads[J]. Journal of Composites for Construction, ASCE, 2001, 5(4): 228-236.

[13] Hanaoka D, Miyazato S, Moriwake A. Fundamental study on repair technology of reinforced concrete [C]. In: Proceedings of the 2nd International Conference on Protection of Structures Against Hazards. Singapore, 2004. 183–190.

[14] Yang Y., Guo C., Cai P., et al. The effect of sea water on CFRP/concrete interface[J]. Industrial Construction, 2006, 136(18): 10-12.

[15] Soudki K., EI-Salakawy E., Craig Brent. Behavior of CFRP strengthened reinforced concrete beams in corrosive environment[J]. Journal of Composites for Construction, ASCE, 2007, 11(3): 291-298.

[16] Yang Yongxin, Wang Jing, Zhang Xiaodong. Research for durability of concrete structures strengthened with carbon fiber reinforced polymer sheets [J]. Port Engineering Technology, 2002(2): 25–27 (in Chinese).

[17] Cai Guangting, Chen Junqiu, Zou Yue et al. Study on the durability of structural adhesive used to adhere steel for strengthening concrete [J]. Concrete, 2000(8): 37–40.

[18] Hu H., Yang Y., Guo C., et al. The effect of the sea water on the durability of resin[J]. Industrial Construction, 2006, 136(18): 13-15.

[19] Täljsten B. Strengthening of concrete prisms using the plate bonding technique[J]. Int J Fract, 1996, 82(1): 253-266.

[20] Pan J., Leung C. K. Y. Effect of concrete composition on FRP/concrete bond capacity[J]. Journal of Composites for Construction, ASCE, 2007, 11(6): 611-618.