DOI QR코드

DOI QR Code

나노 실리카를 혼입한 하이볼륨 플라이애시 콘크리트의 수화도 및 역학적 특성

Hydration and Mechanical Properties of High-volume Fly Ash Concrete with Nano-silica

  • 차수원 (울산대학교 토목공학과) ;
  • 이건욱 (가천대학교 토목환경공학과) ;
  • 최영철 (가천대학교 토목환경공학과)
  • 투고 : 2022.10.07
  • 심사 : 2022.11.10
  • 발행 : 2022.12.31

초록

최근 탄소중립에 관한 관심이 높아지면서 건설 산업에서 하이볼륨 플라이애시 콘크리트를 사용하는 연구가 다양하게 수행되고 있다. 하지만 HVFC는 초기 압축강도가 낮은 단점이 있어, 이를 개선하기 위해 나노 소재를 활용한 연구에 대한 관심이 높아지고 있다. 나노 실리카는 포졸란 재료로서 이러한 조기 강도 지연을 보완할 것으로 기대된다. 따라서 본 연구에서는 나노 실리카를 HVFC에 혼입하여 초기 수화반응에 미치는 영향과 이에 따른 미세구조의 개선에 대해 조사하였다. 초기 수화반응은 응결실험과 미소수화열을 통해 분석하였고, 재령에 따른 압축강도와 열중량 분석을 진행하였다. 미세구조 개선의 효과는 수은압입법을 통해 평가하였다. 실험결과 나노실리카를 혼입하였을 때, 초기 강도가 증가하였고 미세구조가 개선되는 것으로 나타났다.

Recently, as carbon neutrality has been important factor in the construction industry, many studies have been conducted on the high-volume fly ash concrete. High volume fly ash concrete(HVFC) is usually made by replacing more than 50% of cement with fly ash. However, HVFC has a disadvantage of low compressive strength in early age. To overcome this shortcoming of HVFC, improve this, interest in techonolgy using nanomaterials is increasing. Nano silica is expected to improve the early age strength of HVFC as a pozzolanic material. This study investigated the effect of nano silica on the early hydration reaction and microstructure of HVFC. The early hydration reaction of HFVC was analyzed through setting time, isothermal calorimeter, compressive strength and thermal weight analysis. In addition, the microstructure of HVFC was measured by mercury intrusion porosimetry. From the test results, it was confirmed that nano silica increased the early age strength and improve the microstructure of HVFC.

키워드

과제정보

이 성과는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(NRF-2020R1A2C2008926).

참고문헌

  1. Prakash, R., Raman, S. N., Subramanian, C., and Divyah, N. (2022), 6 - Eco-friendly fiber-reinforced concretes, Handbook of Sustainable Concrete and Industrial Waste Management, 109-145.
  2. Sahoo, S., Das, B. B., and Mustakim, S. (2017), Acid, alkali, and chloride resistance of concrete composed of low-carbonated fly ash. J. Mater. Civ. Eng., 29(3), 1-12.
  3. Bagheri, A. R., Zanganeh, H., and Moalemi, M. M. (2012), Mechanical and durability properties of ternary concretes containing silica fume and low reactivity blast furnace slag, Cem. Concr. Compos, 34(5), 663-670. https://doi.org/10.1016/j.cemconcomp.2012.01.007
  4. de Sensale, G. R., (2006), Strength development of concrete with rice husk ash. Cem. Concr. Compos, 28(2), 158-160. https://doi.org/10.1016/j.cemconcomp.2005.09.005
  5. Giner, V.T., Ivorra, S., Baeza, F. J., Zornoza, E., and Ferrer, B. (2011), Silica fume admixture effect on the dynamic properties of concrete. Constr. Build. Mater., 25(8), 3272-3277. https://doi.org/10.1016/j.conbuildmat.2011.03.014
  6. Obla, K. H., Hill, R.L., Thomas, M. D. A., Shashiprakash, S. G., and Perebatova, O. (2003), Properties of concrete containing ultra-fine fly ash, ACI Mater. J, 100(5), 426-433.
  7. Copeland, K. D., Obla, K. H., Hill, R. L., and Thomas, M. D. (2001), A. Ultra Fine Fly Ash for High Performance Concrete. In Construction Institute Sessions at ASCE Civil Engineering Conference , Houston, Texas, USA,166-175.
  8. Das, B. B., Singh, D. N., and Pandey, S. P. (2012), Rapid chloride ion permeability of OPC- and PPC-based carbonated concrete. J. Mater. Civ. Eng, 24(5), 606-611. https://doi.org/10.1061/(ASCE)MT.1943-5533.0000415
  9. Paya, J., Monzo, J., Borrachero, M. V., Peris-Mora, E., and Amahjour, F. (2000), Mechanical treatment of fly ashes: Part IV. Strength development of ground fly ash-cement mortars cured at different temperatures. Cem. Concr. Res. ,30(4), 543-551. https://doi.org/10.1016/S0008-8846(00)00218-0
  10. Qian, J., Shi, C., and Wang, Z. (2001) Activation of blended cements containing fly ash. Cem. Concr. Res, 31(8), 1121-1127. https://doi.org/10.1016/S0008-8846(01)00526-9
  11. Babaian, P. M., Wang, K., Mishulovich, A., Bhattacharja, S., and Shah, S.P. (2003), Effect of mechanochemical activation on reactivity of cement kiln dust-fly ash systems. ACI Mater. J, 100(1), 55-62.
  12. Goni, S., Guerrero, A., Luxan, M.P., and Macias, A. (2003), Activation of the fly ash pozzolanic reaction by hydrothermal conditions. Cem. Concr. Res, 33(9), 1399-1405. https://doi.org/10.1016/S0008-8846(03)00085-1
  13. Wang, K., Shah, S.P., and Mishulovich, A. (2004), Effects of curing temperature and NaOH addition on hydration and strength development of clinker-free CKD-fly ash binders. Cem. Concr. Res, 34(2), 299-309. https://doi.org/10.1016/j.cemconres.2003.08.003
  14. Yang, G., Wu, T., Fu, C., and Ye, H. (2021), Effects of activator dosage and silica fume on the properties of Na2SO4-activated high-volume fly ash. Constr. Build. Mater, 278, 1-9.
  15. Chuah, S., Pan, Z., Sanjayan, J.G., Wang, C.M., and Duan, W.H. (2014), Nano reinforced cement and concrete composites and new perspective from graphene oxide. Constr. Build. Mater, 73, 113-124. https://doi.org/10.1016/j.conbuildmat.2014.09.040
  16. Du, H., and Pang, S.D. (2015), Enhancement of barrier properties of cement mortar with graphene nanoplatelet. Cem. Concr. Res, 76, 10-19. https://doi.org/10.1016/j.cemconres.2015.05.007
  17. Li, H., Xiao, H., and Ou, J. (2004), A study on mechanical and pressure-sensitive properties of cement mortar with nanophase materials. Cem. Concr. Res, 34(3), 435-438. https://doi.org/10.1016/j.cemconres.2003.08.025
  18. Silvestre, J., Silvestre, N., and de Brito, J.(2016), Review on concrete nanotechnology. Eur. J. Environ. Civ. Eng. 20(4), 455-485. https://doi.org/10.1080/19648189.2015.1042070
  19. Wang, Y., Hughes, P., Niu, H., and Fan, Y.(2019), A new method to improve the properties of recycled aggregate concrete: Composite addition of basalt fiber and nano silica. J. Clean, 236, 1-12.
  20. Yesilmen, S., Al-Najjar, Y., Balav, M.H., Sahmaran, M., Yildirim, G., and Lachemi, M. (2015), Nano-modification to improve the ductility of cementitious composites. Cem. Concr. Res, 76, 170-179. https://doi.org/10.1016/j.cemconres.2015.05.026
  21. Senff, L., Tobaldi, D.M., Lucas, S., Hotza, D., Ferreira, V.M., and Labrincha, J.A. (2013), Formulation of mortars with nano-SiO2 and nano-TiO2 for degradation of pollutants in buildings, Compos. B. Eng., 44(1), 40-47. https://doi.org/10.1016/j.compositesb.2012.07.022
  22. Li, G. (2004), Properties of high-volume fly ash concrete incorporating nano-SiO2. Cem. Concr. Res., 34(6), 1043-1049. https://doi.org/10.1016/j.cemconres.2003.11.013
  23. Kong, D., Du, X., Wei, S., Zhang, H., Yang, Y., and Shah, S.P. (2012), Influence of nano-silica agglomeration on microstructure and properties of the hardened cement-based materials, Constr. Build. Mater., 37, 707-715. https://doi.org/10.1016/j.conbuildmat.2012.08.006
  24. Kawashima, S., Hou, P., Corr, D.J., and Shah, S.P. (2013), Modification of cement-based materials with nanoparticles, Cem. Concr. Compos., 36, 8-15. https://doi.org/10.1016/j.cemconcomp.2012.06.012
  25. Ghafari, E., Costa, H., Julio, E., Portugal, A., and Duraes, L. (2014), The effect of nano silica addition on flowability, strength and transport properties of ultra high performance concrete, Mater. Des., 59, 1-9. https://doi.org/10.1016/j.matdes.2014.02.051
  26. Liu, H., Li, Q., Ni, S., Wang, L., Yue, G., and Guo, Y. (2022), Effect of nano-silica dispersed at different temperatures on the properties of cement-based materials. J. Build. Eng. 46, 103750. https://doi.org/10.1016/j.jobe.2021.103750
  27. Wu, Z., Khayat, K.H., and Shi, C. (2017), Effect of nano-SiO2 particles and curing time on development of fiber-matrix bond properties and microstructure of ultra-high strength concrete. Cem. Concr. Res. 95, 247-256. https://doi.org/10.1016/j.cemconres.2017.02.031
  28. Chithra, S., Senthil Kumar, S.R.R., and Chinnaraju, K. (2016), The effect of colloidal nano-silica on workability, mechanical and durability properties of high-performance concrete with copper slag as partial fine aggregate. Constr. Build. Mater. 113, 794-804. https://doi.org/10.1016/j.conbuildmat.2016.03.119
  29. Xi, B., Zhou, Y., Yu, K., Hu, B., Huang, X., Sui, L., and Xing, F. (2020), Use of nano-SiO2 to develop a high performance green lightweight engineered cementitious composites containing fly ash cenospheres. J. Clean. 262, 1-14.
  30. Pacheco-Torgal, F., Miraldo, S., Ding, Y., and Labrincha, J.A. (2013), Targeting HPC with the help of nanoparticles: An overview. Constr. Build. Mater. 38, 365-370. https://doi.org/10.1016/j.conbuildmat.2012.08.013
  31. Yu. R., Spiesz. P., and Brouwers. H.J.H. (2014), Effect of nano-silica on the hydration and microstructure development of ultra-high- performance concrete (UHPC) with a low binder amount, Constr. Build. Mater. 65, 140-150. https://doi.org/10.1016/j.conbuildmat.2014.04.063
  32. Lee. S.H. (2003) About the pozzolanic reaction. Cement, 158, 40-44.
  33. Moon, G.D., Oh, S., and Choi, Y.C.(2016), Effects of the physicochemical properties of fly ash on the compressive strength of high-volume fly ash mortar. Constr. Build. Mater. 124, 1072-1080. https://doi.org/10.1016/j.conbuildmat.2016.08.148
  34. Hanif, A., Parthasarathy, P., Ma, H., Fan, T., and Li, Z. (2017), Properties improvement of fly ash cenosphere modified cement pastes using nano silica. Cem. Concr. Compos. 81, 35-48. https://doi.org/10.1016/j.cemconcomp.2017.04.008
  35. Kim. M.S., Jun. Y.b., Lee. C.H., and Oh. J.E. (2013), Use of CaO as an activator for producing a pricecompetitive non-cement structural binder using ground granulated blast furnace slag. Cem Concr Res. 54, 208-214. https://doi.org/10.1016/j.cemconres.2013.09.011