Advances in concrete construction

  • 제12권6호
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  • Pages.507-515
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  • 2021
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  • 2287-5301(pISSN)
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  • 2287-531X(eISSN)
테크노프레스 (Techno-Press)
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DOI QR코드

DOI QR Code

Investigation on alkalinity of pore solution and microstructure of hardened cement-slag pastes in purified water

  • Hu, Ya-Ru (Department of Civil Engineering, Nanjing University of Science and Technology) ;
  • Zuo, Xiao-Bao (Department of Civil Engineering, Nanjing University of Science and Technology) ;
  • Li, Xiang-Nan (Department of Civil Engineering, Nanjing University of Science and Technology) ;
  • Jiang, Dong-Qi (Department of Civil Engineering, Nanjing University of Science and Technology)
  • 투고 : 2020.07.20
  • 심사 : 2021.12.04
  • 발행 : 2021.12.25
⟨ 이전 논문 다음 논문 ⟩

초록

To evaluate the influence of slag on the alkalinity of pore solution and microstructure of concrete, this paper performs a leaching experiment on hardened cement-slag pastes (HCSP) slice specimens with different slag content in purified water. The pH value of pore solution, average porosity, morphology, phase composition and Ca/Si of HCSP specimens in the leaching process are measured by solid-liquid extraction, saturated-dried weighing, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) and X-ray diffraction (XRD). Results shows that the addition of slag can mitigate an increase in porosity and a decrease in Ca/Si of HCSP in the leaching process. Besides, an appropriate slag content can improve the microstructure so as to obtain the optimum leaching resistance of HCSP, which can guarantee the suitable alkalinity of pore solution to prevent a premature corrosion of reinforced bar. The optimum slag content is 40% in HCSP with a water-binder ratio of 0.45, and an excessive slag causes a significant decrease in the alkalinity of pore solution, resulting in a loss of protection on reinforced bar in HCSP.

키워드

과제정보

The study of this paper is financially supported by the National Natural Science Foundation of China (51778297, 52078252).

참고문헌

  1. Alonso, C., Castellote, M., Llorente, I. and Andrade, C. (2006), "Ground water leaching resistance of high and ultra high performance concretes in relation to the testing convection regime", Cement Concrete Res., 36(9), 1583-1594. http://doi.org/10.1016/j.cemconres.2006.04.004.
  2. Awoyera, P.O., Dawson, A.R., Thom, N.H. and Akinmusuru, J.O. (2017), "Suitability of mortars produced using laterite and ceramic wastes: Mechanical and microscale analysis", Constr. Build. Mater., 148, 195-203. http://doi.org/10.1016/j.conbuildmat.2017.05.031.
  3. Awoyera, P.O., Akinmusuru, J.O. and Dawson, A.R. (2018), "Microstructural characteristics, porosity and strength development in ceramic-laterized concrete", Cement Concrete Compos., 86, 224-237. http://doi.org/10.1016/j.cemconcomp.2017.11.017.
  4. Bellifa, S. and Boumechra, N. (2019), "Effects of calcium leaching on the physical and mechanical properties of aerial lime-cement mortars", J. Eng. Des., 17(3), 649-66. http://doi.org/10.1108/JEDT-11-2018-0199.
  5. Cherif, R., Hamami, A. and At-Mokhtar, A. (2020), "Effects of leaching and chloride migration on the microstructure and pore solution of blended cement pastes during a migration test", Constr. Build. Mater., 240, 117934. http://doi.org/10.1016/j.conbuildmat.2019.117934.
  6. Choi, Y.S., Choi, S.Y., Kim, I.S. and Yang, E.I. (2018), "Experimental study on the structural behaviour of calcium-leaching damaged concrete members", Mag. Concrete Res., 70(21), 1102-1117. http://doi.org/10.1680/jmacr.17.00297.
  7. Choi, Y.S., Kim, J.G. and Lee, K.M. (2006), "Corrosion behavior of steel bar embedded in fly ash concrete", Corros. Sci., 48(7), 1733-1745. http://doi.org/10.1016/j.corsci.2005.05.019.
  8. Ping, D.A., Zsa, B., Wei, C.A. and Cs, C. (2013), "Efficiency of mineral admixtures in concrete: Microstructure, compressive strength and stability of hydrate phases", Appl. Clay Sci., 83, 115-121. http://doi.org/10.1016/j.clay.2013.08.021.
  9. Figueira, R.B., Sadovski, A., Melo, A.P. and Pereira, E.V. (2017), "Chloride threshold value to initiate reinforcement corrosion in simulated concrete pore solutions: The influence of surface finishing and pH", Constr. Build. Mater., 141, 183-200. http://doi.org/10.1016/j.conbuildmat.2017.03.004.
  10. Gunasekara, C., Zhou, Z., Law, D.W., Sofi, M. and Mendis, P. (2020), "Microstructure and strength development of quaternary blend high-volume fly ash concrete", J. Mater. Sci., 55(15), 6441-6456. http://doi.org/10.1007/s10853-020-03864473-1.
  11. GB 175 (2007), Chinese National Standard for Common Portland Cement, Standardization Administration of China, Beijing, China.
  12. GB/T 203 (2008), Chinese National Standard for Granulated blastfurnace slag used for cement production, Standardization Administration of China, Beijing, China.
  13. Hu, H.H., Zuo, X.B., Cui, D. and Tang, Y.J. (2019), "Experimental study on leaching-abrasion behavior of concrete in flowing solution with low velocity", Constr. Build. Mater., 224, 762-772. http://doi.org/10.1016/j.conbuildmat.2019.07.125.
  14. Jain, J. and Neithalath, N. (2009), "Analysis of calcium leaching behavior of plain and modified cementpastes in pure water", Cement Concrete Compos., 31(3), 176-185. http://doi.org10.1016/j.cemconcomp.2009.01.003.
  15. Jia, Y., Bian, H.B., Xie, S.Y., Burlion, N. and Shao, J.F. (2017), "A numerical study of mechanical behavior of a cement paste under mechanical loading and chemical leaching", Int. J. Num. Anal. Meth., 41(18), 1848-1869. http://doi.org/10.1002/nag.2703.
  16. Jiang, W.G., Li, X.G., Lv, Y., Jiang, D.B. and He, C.H. (2020), "Mechanical and hydration properties of low clinker cement containing high volume superfine blast furnace slag and nano silica", Constr. Build. Mater., 238, 117683. http://doi.org/10.1016/j.conbuildmat.2019.117683.
  17. Li, X., Grasley, Z.C., Garboczi, E.J. and Bullard, J.W. (2017), "Simulation of the influence of intrinsic C-S-H aging on time-dependent relaxation of hydrating cement paste", Constr. Build. Mater., 157, 1024-1031. http://doi.org/10.1016/j.conbuildmat.2017.09.178.
  18. Li, X. and Yan, P. (2010), "Influence of fly ash content on alkalinity of pore solution and microstructure of cement pastes", J. Build. Eng., 13(6), 787-791. http://doi.org/10.3969/j.issn.1007-9629.2010.06.017.
  19. Liu, R.Y., Chi, Y., Chen, S.Y., Jiang, Q.H., Meng, X.Y., Wu, K. and Li, S.J. (2020), "Influence of pore structure characteristics on the mechanical and durability behavior of pervious concrete material based on image analysis", Int. J. Concrete Struct. Mater., 14(1). http://doi.org/10.1186/s40069-020-00404-1.
  20. Majhi, R.K., Nayak, A.N. and Mukharjee, B.B. (2020), "Characterization of lime activated recycled aggregate concrete with high-volume ground granulated blast furnace slag", Constr. Build. Mater., 259, 119882. http://doi.org/10.1016/j.conbuildmat.2020.119882.
  21. Majhi, R.K. and Nayak, A.N. (2019), "Bond, durability and microstructural characteristics of ground granulated blast furnace slag based recycled aggregate concrete", Constr. Build. Mater., 212, 578-595. https://doi.org/10.1016/j.conbuildmat.2019.04.017.
  22. Majhi, R.K. and Nayak, A.N. (2020), "Production of sustainable concrete utilising high-volume blast furnace slag and recycled aggregate with lime activator", J. Clean. Prod., 255, 120188. http://doi.org/10.1016/j.jclepro.2020.120188.
  23. Melchers, R.E. and Chaves, I.A. (2020), "Durability of reinforced concrete bridges in marine environments", Struct. Infrastruct. Eng., 16(1), 169-180. http://doi.org/10.1080/15732479.2019.1604769.
  24. Mohamed, O.A. (2019), "A review of durability and strength characteristics of alkali-activated slag concrete", Mater., 12(8), 1198. https://doi.org/10.3390/ma12081198.
  25. Mehta, P. and Saloni, A. (2019), "Effect of ultra-fine slag on mechanical and permeability properties of metakaolin-based sustainable geopolymer concrete", Adv. Concrete Constr., 7(4), 231-239. https://doi.org/10.12989/acc.2019.7.4.231.
  26. Popov, V., Popov, D. and Davidenko, A. (2018), "Complex characteristic for forecasting durability of hydraulic concrete", MATEC Web Conf., 196, 04007. https://doi.org/10.1051/matecconf/201819604007.
  27. Proske, T., Rezvani, M., Palm, S., Muller, C. and Graubner, C.A. (2018), "Concretes made of efficient multi-composite cements with slag and limestone", Cement Concrete Compos., 89, 107-119. http://doi.org/10.1016/j.cemconcomp.2018.02.012.
  28. Pu, Q., Yao, Y., Wang, L., Shi, X.X., Luo, J.J. and Xie, Y.F. (2017), "The investigation of pH threshold value on the corrosion of steel reinforcement in concrete", Comput. Concrete, 19(3), 257-262. http://doi.org/10.12989/cac.2017.19.3.257.
  29. Rafieizonooz, M., Mirza, J., Salim, M.R., Hussin, M.W. and Khankhaje, E. (2016), "Investigation of coal bottom ash and fly ash in concreteas replacement for sand and cement", Constr. Build. Mater., 116, 15-24. http://doi.org/10.1016/j.conbuildmat.2016.04.080.
  30. Ramakrishnan, K., Pugazhmani, G., Sripragadeesh, R., Muthu, D. and Venkatasubramanian, C. (2017), "Experimental study on the mechanical and durability properties of concrete with waste glass powder and ground granulated blast furnace slag as supple mentary cementitious materials", Constr. Build. Mater., 156, 739-749. http://doi.org/10.1016/j.conbuildmat.2017.08.183.
  31. Rao, M.J., Wei, J.P., Gao, Z.Y., Zhou, W., Li, Q.L. and Liu, S.H. (2016), "Study on strength and microstructure of cement-based materials containing combination mineral admixtures", Adv. Mater. Sci. Eng., 2016, 7243670. http://doi.org/10.1155/2016/7243670.
  32. Patel, R.A., Perko, J., Jacques, D., Schutter, G.D., Ye, G. and Breugel, K.V. (2018), "A three-dimensional lattice Boltzmann method based reactive transport model to simulate changes in cement paste microstructure due to calcium leaching", Constr. Build. Mater., 166, 158-170. http://doi.org/10.1016/j.conbuildmat.2018.01.114.
  33. Rashad, A.M. (2018), "An overview on rheology, mechanical properties and durability of high-volume slag used as a cement replacement in paste, mortar and concrete", Constr. Build. Mater., 187, 89-117. https://doi.org/10.1016/j.conbuildmat.2018.07.150.
  34. Razak, H.A. and Sajedi, F. (2011), "The effect of heat treatment on the compressive strength of cement-slag mortars", Mater. Des., 32(8-9), 4618-4628. http://doi.org/10.1016/j.matdes.2011.04.038.
  35. Roh, H., Park, C. and Moon, D.Y. (2017), "Experimental investigation of the effects of concrete alkalinity on tensile properties of preheated structural GFRP rebar", Adv. Mater. Sci. Eng., 2017, 6327848. http://doi.org/10.1155/2017/6327848.
  36. Saeki, T. and M. and Monteiro, P.J. (2005), "A model to predict the amount of calcium hydroxide in concrete containing mineral admixtures", Cement. Concrete. Res., 35(10), 1914-1921. http://doi.org/10.1016/j.cemconres.2004.11.018.
  37. Sahani, A.K., Samanta, A.K. and Roy, D. (2019), "Influence of mineral by-products on compressive strength and microstructure of concrete at high temperature", Adv. Concrete Constr., 7(4), 263-275. http://doi.org/10.12989/acc.2019.7.4.263.
  38. Savija, B., Zhang, H. and Schlangen, E. (2020), "Micromechanical testing and modelling of blast furnace slag cement pastes", Constr. Build. Mater., 239, 117841. http://doi.org/10.1016/j.conbuildmat.2019.117841.
  39. Tang, Y.J., Zuo, X.B., He, S.L., Ayinde, O. and Yin, G.J. (2016), "Influence of slag content and water-binder ratio on leaching behavior of cement pastes", Constr. Build. Mater., 129, 61-69. http://doi.org/10.1016/j.conbuildmat.2016.11.003.
  40. Wang, W., Chen, H., Li, X. and Zhu, Z. (2017), "Corrosion behavior of steel bars immersed in simulated pore solutions of alkali-activated slag mortar", Constr. Build. Mater., 143, 289-297. http://doi.org/10.1016/j.conbuildmat.2017.03.132.
  41. Wang, X., Xu, K., Li, Y. and Guo, S. (2018), "Dissolution and leaching mechanisms of calcium ions in cement based materials", Constr. Build. Mater., 180, 103-108. http://doi.org/10.1016/j.conbuildmat.2018.05.225.
  42. Wang, Y., Shui, Z., Sun, T., Huang, Y. and Wang, G. (2018), "Effect of fly ash, sinking beads and metakaolin on the workability, strength, free shrinkage and chloride resistance of concretes: A comparative study", Arab. J. Sci. Eng., 43(10), 5243-5254. http://doi.org/10.1007/s13369-018-3068-7.
  43. Jin, W. and Wu, W. (2010), "Study on wireless sensing for monitoring the corrosion of reinforcement in concrete structures", Meas., 43(3), 375-380. http://doi.org/10.1016/j.measurement.2009.12.003.
  44. Wang, X.Y. and Lee, H.S. (2014), "Prediction of compressive strength of slag concrete using a blended cement hydration model", Comput. Concrete, 14(3), 247-262. http://doi.org/10.12989/cac.2014.14.3.247.
  45. Yu, X., Chen, J., Xu, Q. and Zhou, Z. (2018), "Research on the influence factors of thermal cracking in mass concrete by model experiments", KSCE. J. Civ. Eng., 22(8), 2906-2915. http://doi.org/10.1007/s12205-017-2711-2.
  46. Zuo, X.B., Jiang, K., Feng, Y.X., Tang, Y.J. and Sun, X.H. (2017), "Analysis on depassivation process and chloride ion threshold of passive film on surface of ductile iron in simulated pore solution", J. Southeast U. Nat. Sci. Ed., 47, 392-396. (in Chinese). http://doi.org/10.3969/j.issn.1001-0505.2017.02.031.