Structural Engineering and Mechanics

  • 제82권2호
  • /
  • Pages.163-172
  • /
  • 2022
  • /
  • 1225-4568(pISSN)
  • /
  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Flexural performance of RC beams incorporating Zinc-rich and epoxy bonding coating layers exposed to fire

  • Tobbala, Dina E. (Department of Civil and Architecture Constructions, Suez University) ;
  • Rashed, Ahmed S. (Department of Physics and Engineering Mathematics, Faculty of Engineering, Zagazig University) ;
  • Tayeh, Bassam A. (Department of Civil Engineering, Faculty of Engineering, Islamic University of Gaza)
  • 투고 : 2021.05.31
  • 심사 : 2022.01.12
  • 발행 : 2022.04.25
⟨ 이전 논문 다음 논문 ⟩

초록

Zinc-rich epoxy (ZRE) is used to overcome corrosion problems in reinforced concrete (RC) beams and coat steel rebars to protect them from humidity and chlorides. An extra coating layer of Sikadur-31 epoxy (SDE) is utilised to increase bond strength because the use of ZRE reduces the bond strength between concrete and steel rebars. However, the low melting point of SDE indicates that concrete specimens are vulnerable to fire. An experimental investigation on flexural performance of RC beams incorporating ZRE-SDE coating of steel rebars that were destroyed by fire is performed in this study. Twenty beams of five concrete mixes with different cementitious contents were tested to compare fire exposure for coated and uncoated rebars of the same beams at room temperature and determine the optimal cementitious content. Scanning electron microscopy (SEM) was also applied to investigate characteristics of fired mixture samples. Results showed that the use of SDE-ZRE at room temperature improves flexural strengths of the five mixes compared with uncoated rebars with percentages ranging from 8.5% to 12.3%. All beams with SDE-ZRE lost approximately 50% of their flexural strength due to firing. Moreover, the mix incorporating SF (silica fume) of 15% and cement content of 400 kg/m3 introduces optimum behaviour compared with other mixes. All results were supported and verified by the SEM analysis and compressive strength of cubic specimens of the same mixes.

키워드

참고문헌

  1. Al-Negheimish, A., Hussain, R.R., Alhozaimy, A. and Singh, D.D.N. (2021), "Corrosion performance of hot-dip galvanized zinc-aluminum coated steel rebars in comparison to the conventional pure zinc coated rebars in concrete environment", Constr. Build. Mater., 274, 121921. https://doi.org/10.1016/j.conbuildmat.2020.121921.
  2. Arianpouya, N., Shishesaz, M., Arianpouya, M. and Nematollahi, M. (2013), "Evaluation of synergistic effect of nanozinc/nanoclay additives on the corrosion performance of zinc-rich polyurethane nanocomposite coatings using electrochemical properties and salt spray testing", Surf. Coat. Technol., 216, 199-206. https://doi.org/10.1016/j.surfcoat.2012.11.036.
  3. Assaad, J.J. and Issa, C.A. (2012), "Bond strength of epoxy-coated bars in underwater concrete", Constr. Build. Mater., 30, 667-674. https://doi.org/10.1016/j.conbuildmat.2011.12.047.
  4. Banjara, N.K., Ramanjaneyulu, K., Banjara, N.K. and Ramanjaneyulu, K. (2019), "Effective CFRP retrofit strategy for flexural deficient RC beams", Struct. Eng. Mech., 69(2), 163-175. http://doi.org/10.12989/sem.2019.69.2.163.
  5. Campione, G. (2021), "Analytical model for flexural and shear strength of normal and high-strength concrete beams", Struct. Eng. Mech., 78(2), 199-207. http://doi.org/10.12989/sem.2021.78.2.199.
  6. Cubides, Y. and Castaneda, H. (2016), "Corrosion protection mechanisms of carbon nanotube and zinc-rich epoxy primers on carbon steel in simulated concrete pore solutions in the presence of chloride ions", Corros. Sci., 109, 145-161. https://doi.org/10.1016/j.corsci.2016.03.023.
  7. Dembovska, L., Bajare, D., Pundiene, I. and Vitola, L. (2017), "Effect of pozzolanic additives on the strength development of high performance concrete", Procedia Eng., 172, 202-210. https://doi.org/10.1016/j.proeng.2017.02.050.
  8. Deya, C., Blustein, G., del Amo, B. and Romagnoli, R. (2010), "Evaluation of eco-friendly anticorrosive pigments for paints in service conditions", Prog. Organ. Coating., 69(1), 1-6. https://doi.org/10.1016/j.porgcoat.2010.03.011.
  9. Goksu, C., Saribas, I., Binbir, E., Akkaya, Y. and Ilki, A. (2019), "Structural performance of recycled aggregates concrete sourced from low strength concrete", Struct. Eng. Mech., 69(1), 77-94. http://doi.org/10.12989/sem.2019.69.1.077.
  10. Hosseini, S.A., Shabakhty, N. and Khankahdani, F.A. (2019), "Sensitivity analysis of flexural strength of RC beams influenced by reinforcement corrosion", Struct. Eng. Mech., 72(4), 479-489. http://doi.org/10.12989/sem.2019.72.4.479.
  11. Irshidat, M.R. and Al-Saleh, M.H. (2017), "Flexural strength recovery of heat-damaged RC beams using carbon nanotubes modified CFRP", Constr. Build. Mater., 145, 474-482. https://doi.org/10.1016/j.conbuildmat.2017.04.047.
  12. Ishimura, T., Lu, R., Yamasaki, K. and Miyakoshi, T. (2010), "Development of an eco-friendly hybrid lacquer based on kurome lacquer sap", Prog. Organ. Coating., 69(1), 12-15. https://doi.org/10.1016/j.porgcoat.2010.04.019.
  13. Jiang, N., Wang, C., Wang, Z., Li, B. and Liu, Y.A. (2021), "Strength characteristics and microstructure of cement stabilized soft soil admixed with silica fume", Mater. (Basel, Switzerland), 14(8), 1929. https://doi.org/10.3390/ma14081929.
  14. Lasia, A. (2014), Electrochemical Impedance Spectroscopy and its Applications, Springer.
  15. Lee, J., Sheesley, E., Jing, Y., Xi, Y. and Willam, K. (2018), "The effect of heating and cooling on the bond strength between concrete and steel reinforcement bars with and without epoxy coating", Constr. Build. Mater., 177, 230-236. https://doi.org/10.1016/j.conbuildmat.2018.05.128.
  16. Marchebois, H., Joiret, S., Savall, C., Bernard, J. and Touzain, S. (2002), "Characterization of zinc-rich powder coatings by EIS and Raman spectroscopy", Surf. Coating. Technol., 157(2), 151-161. https://doi.org/10.1016/S0257-8972(02)00147-0.
  17. Marchebois, H., Keddam, M., Savall, C., Bernard, J. and Touzain, S. (2004), "Zinc-rich powder coatings characterisation in artificial sea water", Electrochimica Acta, 49(11), 1719-1729. https://doi.org/10.1016/j.electacta.2003.11.031.
  18. Megahed, M., Tobbala, D.E. and El-baky, M.A. (2020), "The effect of incorporation of hybrid silica and cobalt ferrite nanofillers on the mechanical characteristics of glass fiberreinforced polymeric composites", Polym. Compos., 42(1), 271-284. https://doi.org/10.1002/pc.25823.
  19. Memon, S.A., Shah, S.F.A., Khushnood, R.A. and Baloch, W.L. (2019), "Durability of sustainable concrete subjected to elevated temperature-A review", Constr. Build. Mater., 199, 435-455. https://doi.org/10.1016/j.conbuildmat.2018.12.040.
  20. Park, J.H., Yun, T.H., Kim, K.Y., Song, Y.K. and Park, J.M. (2012), "The improvement of anticorrosion properties of zinc-rich organic coating by incorporating surface-modified zinc particle", Prog. Organ. Coating., 74(1), 25-35. https://doi.org/10.1016/j.porgcoat.2011.09.012.
  21. Park, S. and Shon, M. (2015), "Effects of multi-walled carbon nano tubes on corrosion protection of zinc rich epoxy resin coating", JIEC J. Indus. Eng. Chem., 21, 1258-1264. http://doi.org/10.1016/j.jiec.2014.05.042.
  22. Pokorny, P., Kouril, M., Stoutil, J., Bouska, P., Simon, P. and Juranek, P. (2015), "Problems and normative evaluation of bond-strength tests for coated reinforcement and concrete= Problemi in normativna ocena preizkusov trdnosti vezi med armaturo s prekritjem in betonom", Mater. Technol., 49(6), 847-856.
  23. Poon, C.S., Azhar, S., Anson, M. and Wong, Y.L. (2001), "Comparison of the strength and durability performance of normal- and high-strength pozzolanic concretes at elevated temperatures", Cement Concrete Res., 31(9), 1291-1300. https://doi.org/10.1016/S0008-8846(01)00580-4.
  24. Rehman, A., Masood, A., Akhtar, S., Ibrahim, S.M. and Shariq, M. (2021), "Experimental and numerical investigation into flexural bond strength of RC beams exposed to elevated temperature", Constr. Build. Mater., 282, 122630. https://doi.org/10.1016/j.conbuildmat.2021.122630.
  25. Schaefer, K. and Miszczyk, A. (2013), "Improvement of electrochemical action of zinc-rich paints by addition of nanoparticulate zinc", Corros. Sci., 66, 380-391. https://doi.org/10.1016/j.corsci.2012.10.004.
  26. Shi, H., Liu, F. and Han, E.H. (2011), "The corrosion behavior of zinc-rich paints on steel: Influence of simulated salts deposition in an offshore atmosphere at the steel/paint interface", Surf. Coating. Technol., 205(19), 4532-4539. https://doi.org/10.1016/j.surfcoat.2011.03.118.
  27. Sika (2020a), Product Data Sheet Sika Zinc Rich®-1.
  28. Sika (2020b), Product Data Sheet Sikadur®-31 CF Normal.
  29. Tobbala, D.E., Abdelsalam, B.A. and Agwa, I.S. (2020), "Bond performance of a hybrid coating zinc-rich epoxy incorporating nano-ferrite for steel rebars subjected to high temperatures in concrete", J. Build. Eng., 32, 101698. https://doi.org/10.1016/j.jobe.2020.101698.
  30. Xu, R., He, T., Yang, R., Da, Y. and Chen, C. (2020), "Application zinc silicate-potassium silicate coating for anticorrosion of steel bar in autoclaved aerated concrete", Constr. Build. Mater., 237, 117521. https://doi.org/10.1016/j.conbuildmat.2019.117521.
  31. Zhang, L., Ma, A., Jiang, J., Song, D., Chen, J. and Yang, D. (2012), "Anti-corrosion performance of waterborne Zn-rich coating with modified silicon-based vehicle and lamellar Zn (Al) pigments", Prog. Nat. Sci., 22(4), 326-333. https://doi.org/10.1016/j.pnsc.2012.07.001.