Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Evaluation of Compressive Strength and Freeze-thaw Resistance Properties of Concrete using Superabsorbent Polymer

고 흡수성 폴리머를 혼입한 콘크리트의 압축 강도 및 동결융해 저항성 평가

  • 김일순 (강릉원주대학교 토목공학과) ;
  • 최소영 (강릉원주대학교 방재연구소) ;
  • 양은익 (강릉원주대학교 토목공학과)
  • Received : 2020.09.02
  • Accepted : 2020.10.16
  • Published : 2020.10.30
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Abstract

When the Superabsorbent Polymer (SAP) is added into concrete, the slump decreases rapidly, deteriorating the workability, the internal curing effect can be obtained through the water absorption and discharge process, and the internal voids of the concrete are increased. In this study, the effects of internal curing and voids were evaluated by evaluating the compressive strength, freeze-thaw resistance, and chloride penetration resistance of SAP-adding concrete that secured workability using a water reducing agent. Also, the internal curing effect of SAP was evaluated by dividing the curing conditions of concrete into water curing and sealed curing. From the result, as the SAP adding ratio increased, the amount of water reducing agent increased, and as for the compressive strength, the SAP adding ratio of 1.5% showed the greatest compressive strength. In particular, in the case of sealed curing showed higher compressive strength than the water curing. It is considered that the compressive strength increased due to the reduction of the effective water-cement ratio and the internal curing effect. Adding 1.0~1.5% of SAP improved the freeze-thaw resistance similar to the case of adding the AE agent, and the addition of more than 1.0% of SAP improved the chloride penetration resistance. The optimal adding ratio of SAP is 1.5%, and the adding ratio of 2.0% or more adversely affects the compressive strength and freeze-thaw resistance.

고 흡수성 폴리머(SAP)가 콘크리트에 혼입되면 슬럼프가 급격하게 감소하여 시공성이 저하되며, 수분 흡수·방출 과정으로 내부 양생 효과를 얻을 수 있고, 콘크리트의 내부 공극을 증가시킨다. 본 연구에서는 감수제를 사용하여 시공성을 확보한 SAP 혼입 콘크리트의 압축강도 및 동결융해 저항성, 염화물 침투 저항성을 평가하여 내부 양생과 공극의 영향을 평가하였다. 또한 콘크리트의 양생 조건을 수중 양생과 봉함 양생으로 구분하여 SAP의 내부 양생 효과를 평가하였다. 실험 결과, SAP 혼입율이 증가할수록 감수제 사용량은 증가하였으며, 압축강도는 SAP 혼입율 1.5%가 가장 큰 압축강도를 나타냈다. 특히, 봉함 양생의 경우 수중 양생보다 큰 압축강도를 나타냈으며, 유효 물-시멘트 비 감소와 내부 양생 효과에 의해 압축강도가 증가한 것으로 판단된다. SAP를 1.0~1.5% 혼입하면 AE제를 혼입한 경우와 유사하게 동결융해 저항성이 개선되었으며, SAP를 1.0% 이상 사용하면 염화물 침투 저항성이 개선되었다. 최적의 SAP 혼입율은 1.5%이며, 2.0% 이상의 혼입율은 압축강도 및 동결융해 저항성에 악영향을 준다.

Keywords

References

  1. Gutema, D.A. and Hong, K.N. (2018). Effect of absorption capacity of super absorbent polymer (SAP) in reducing autogenous shrinkage, Proceedings of the Korea Institute for Structural Maintenance and Inspection, Korea Institute for Structural Maintenance and Inspection, 22(2), 337-338.
  2. Hasholt, M.T., Jensen, O.M. and Laustsen, S. (2015). Superabsorbent polymers as a means of improving frost resistance of concrete. Advances in Civil Engineering Materials, 4(1), 237-256.
  3. Hasholt, M.T., Jensen, O.M., Kovler, K., and Zhutovsky, S. (2012). Can superabsorent polymers mitigate autogenous shrinkage of internally cured concrete without compromising the strength? Construction and Building Materials, 31, 226-230. https://doi.org/10.1016/j.conbuildmat.2011.12.062
  4. Jensen, O.M. (2013). Use of Superabsorbent Polymer in Concrete - An overview of the possibilities offered by using these smart materials as concrete admixtures. Concrete International, 35, 48-52.
  5. Jensen, O.M., and Hansen, P.F. (2001). Water-entrained cement-based materials-I. Principles and theoretical background, Cement and Concrete Research, 31(4), 647-654. https://doi.org/10.1016/S0008-8846(01)00463-X
  6. Jensen, O.M., and Hansen, P.F. (2002). Water-entrained cement-based materials-II. Experimental observations, Cement and Concrete Research, 32(6), 973-978. https://doi.org/10.1016/S0008-8846(02)00737-8
  7. Justs, J., Wyrzykowski, M., Bajare, D., and Lura, P. (2015). Internal curing by superabsorbent polymers in ultra-high performance concrete. Cement and Concrete Research, 76, 82-90. https://doi.org/10.1016/j.cemconres.2015.05.005
  8. Kang, S.H., Hong, S.G., and Moon, J.H. (2018). The effect of superabsorbent polymer on various scale of pore structure in ultra-high performance concrete. Construction and Building Materials, 172, 29-40. https://doi.org/10.1016/j.conbuildmat.2018.03.193
  9. Kang, S.H., Moon, J.H., and Hong, S.G. (2016). Effect of Internal Curing by Super-Absorbent Polymer (SAP) on Hydration, Autogenous Shrinkage, Durability and Mechanical Characteristics of Ultra-High Performance Concrete (UHPC). Journal of the Korea Concrete Institute, 28(3), 317-328. (in Korean) https://doi.org/10.4334/JKCI.2016.28.3.317
  10. Kim, I.S., Lee, C.K., Kim, S., Choi, H.E., Choi, S.Y., and Yang, E.I. (2019). Absorption Characteristics of Superabsorbent Polymer with Particle Types and Test Method, Proceedings of the Korea Concrete Institute Conference, Korea Concrete Institute, 31(1), 403-404. (in Korean)
  11. Kim, J.H., Cho, Y.K., and Lee, K.M. (2018). The Characteristics of Compressive Strength in Mortar with Internal Curing According to Curing Condition, J. Rec. Const. Resources, 6(2), 87-93. (in Korean)
  12. Laustsen, S., Hasholt, M.T. and Jensen, O.M. (2013). Void structure of concrete with superabsorbent polymers and its relastion to frost resistance of concrete, Materials and Structures, 48(1-2), 357-368. https://doi.org/10.1617/s11527-013-0188-0
  13. Lee, C.K., Kim, I.S., Choi, S.Y., and Yang, E.I. (2020). Evaluation of Fundamental Properties and CHloride Penetration Resistance of Concrete using Superabsorbent Polymers. Journal of the Korea Institute for Structural Maintenance and Inspection, 24(2), 50-59. (in Korean) https://doi.org/10.11112/JKSMI.2020.24.2.50
  14. Liu, J., Farzadnia, N., and Shi, C. (2020). Effects of superabsorbent polymer on interfacial transition zone and mechanical properties of ultra-high performance concrete. Construction and Building Materials, 231, 117142. https://doi.org/10.1016/j.conbuildmat.2019.117142
  15. Liu, J., Farzadnia, N., Shi, C., and Ma, X. (2019a). Effects of superabsorbent polymer on shrinkage properties of ultra-high strength concrete under drying condition. Construction and Building Materials, 215, 799-811. https://doi.org/10.1016/j.conbuildmat.2019.04.237
  16. Liu, J., Farzadnia, N., Shi, C., and Ma, X. (2019b). Shrinkage and strength development of UHSC incorporating a hybrid system of SAP and SRA. Cement and Concrete Composites, 97, 175-189. https://doi.org/10.1016/j.cemconcomp.2018.12.029
  17. Ma, X., Liu, J., Wu, Z., and Shi, C. (2017). Effects of SAP on the properties and pore structure of high performance cement-based materials. Construction and Building Materials, 131, 476-484. https://doi.org/10.1016/j.conbuildmat.2016.11.090
  18. Ma, X., Yuan, Q., Liu, J., and Shi, C. (2019). Effect of water absorption of SAP on the rheological properties of cement-based materials with ultra-low w/b ratio. Construction and Building Materials, 195, 66-74. https://doi.org/10.1016/j.conbuildmat.2018.11.050
  19. Mechtcherine, V., Reinhardt, H.W. (2010). Application of superabsorbent polymers (SAP) in concrete construction. State of the Art Report Prepared by Technical Committee 225-SAP, 1-169.
  20. Monnig, S. and Lura, P. (2007). Superabsorbent Polymers-An additive to increase the rfreeze-thaw resistance of high strength concrete. Advances in Construction Materials 2007, 351-358.
  21. Schrofl, C., Mechtcherine, V., and Gorges, M. (2012). Relation between the molecular structure and the efficiency of superabsorbent polymers (SAP) as concrete admixture to mitigate autogenous shrinkage. Cement and Concrete Research, 42(6), 865-873. https://doi.org/10.1016/j.cemconres.2012.03.011
  22. Shen, D., Wang, M., Chen, Y., Wang, W., and Zhang, J. (2017). Prediction of internal relative humidity in concrete modified with superabsorbent polymers at early age. Construction and Building Materials, 149, 543-552. https://doi.org/10.1016/j.conbuildmat.2017.05.121
  23. Shen, D., Wang, X., Cheng, D., Zhang, J., and Jiang, G. (2016). Effect of internal curing with super absorbent polymers on autogenous shrinkage of concrete at early age. Construction and Building Materials, 106(1), 512-522. https://doi.org/10.1016/j.conbuildmat.2015.12.115
  24. Shim, W.B., Hong, K.N., Batmunkh, G.O., and Yeon, Y.M. (2019). Evaluation of self shrinkage characteristics of concrete with super absorbent polymer, Proceedings of the Korea Institute for Structural Maintenance and Inspection, Korea Institute for Structural Maintenance and Inspection, 23(2), 188. (in Korean)
  25. Snoeck, D., Jensen, O. M., and De Belie, N. (2015). The influence of superabsorbent polymers on the autogenous shrinkage properties of cement pastes with supplementary cementitious materials. Cement and Concrete Research, 74, 59-67. https://doi.org/10.1016/j.cemconres.2015.03.020
  26. Yang, J., and Wang, F. (2019). Influence of assumed absorption capacity of superabsorbent polymers on the microstructure and performance of cement mortars. Construction and Building Materials, 204, 468-478. https://doi.org/10.1016/j.conbuildmat.2019.01.225
  27. Yang, J., Liu, L., Liao, Q., Wu, J., Li, J., and Zhang, L. (2019). Effect of superabsorbent polymers on the drying and autogenous shrinkage properties of self-leveling mortar. Construction and Building Materials, 201, 401-407. https://doi.org/10.1016/j.conbuildmat.2018.12.197
  28. Zhong, P., Wyrzykowski, M., Toropovs, N., Li, L., Liu, J., and Lura, P. (2019). Internal curing with superabsorbent polymers of different chemical structures. Cement and Concrete Research, 123, 105-789.