Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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The Rheology of Cement Paste Using Polycarboxylate-Based Superplasticizer for Normal Strength-High Fluidity Concrete

보통강도 고유동 콘크리트용 PC계 고성능 감수제를 사용한 시멘트 페이스트의 레올로지 특성 평가

  • Kong, Tae-Woong (Department of Architectural Engineering, Hanyang University ERICA) ;
  • Lee, Han-Seung (Department of Architectural Engineering, Hanyang University ERICA)
  • 공태웅 (한양대학교 건축시스템공학과) ;
  • 이한승 (한양대학교 건축시스템공학과)
  • Received : 2021.08.06
  • Accepted : 2021.08.26
  • Published : 2021.09.30
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Abstract

General high fluidity concrete is the area of high strength concrete with a high amount of cement to secure the required fluidity and workability. Since most of the concrete structures currently used have normal strength, there is a limit to the practical expansion and practicality of use. Thus it is necessary to develop normal strength-high fluidity concrete with low binders that can be used not only in general buildings but also in special buildings, and can greatly reduce construction time and save labor costs. This requires to develop and apply the polycarboxylate-based superplasticizer. In this study, PCE was prepared for each combination of starting materials(WR, HB, RT) and the rheological properties of cement paste were analyzed using ringflow cone and a rotary viscometer. As a result, when PCE with a combination of WR 80%, HB 6.5%, and RT 13.5% was applied, the yield stress can be minimized while securing the plastic viscosity at level of the normal strength. In addition, high fluidity due to the high dispersion effect was confirmed.

기존 고유동 콘크리트는 소요의 유동성과 작업성 확보를 위해 대부분 단위시멘트량이 높은 고강도 콘크리트 영역으로써, 현재 사용되고 있는 대부분의 콘크리트 구조물이 보통강도(18~35MPa) 수준임을 감안한다면 현실적인 사용범위확대 및 실용성에 한계가 있었다. 고유동 콘크리트의 사용범위를 확대하기 위해 보통강도 수준에서도 유동성과 점성을 발휘할 수 있고 일반건축물뿐만 아니라 특수건축물에서도 사용가능하며, 타설시간과 인건비를 대폭 감축할 수 있는 보통강도 고유동 콘크리트의 개발이 필요한 실정이다. 보통강도 고유동 콘크리트의 개발은 유동성 및 점성을 발휘하여 자기 충전성을 확보함으로써 다짐작업 최소화에 따른 인건비 감축, 공사비 절감, 공기 단축 등의 시공효율성 뿐만 아니라 공사품질을 향상시킬 수 있다. 본 연구에서는 출발원료(WR, HB, RT)의 조합별로 PCE를 제조하고 링플로콘과 회전형 점도계를 사용하여 시멘트 페이스트의 레올로지 특성을 분석하였다. 실험결과 WR 80%, HB 6.5% RT 13.5%를 조합한 PCE를 적용할 경우, 결합재량이 낮은 보통강도 고유동 콘크리트에서 소성점도를 확보하면서 항복응력은 최소화시킬 수 있으며 동시에 높은 분산효과로 인한 고유동성의 확보가능성을 확인할 수 있었다.

Keywords

Acknowledgement

본 연구는 2020년 과학기술정보통신부의 재원으로 한국연구재단의 지원을 받아 수행된 연구(No.2015R1A 5A1037548) 임을 밝히며 이에 감사를 드립니다.

References

  1. Choi, S.W., Jo, H.T., Ryu, D.H., Kim, G.Y. (2012). An experimental study on the influence of the qualities of ordinary portland cement on the flow ability of high flow concrete, Journal of the Korea Concrete Institute, 24(1), 37-44 [in Korean]. https://doi.org/10.4334/JKCI.2012.24.1.037
  2. Jeong, J.G. (2011). A Study on the Development and Application of Normal Strength-High Fluidity Concrete using Powdered Mixing System, Master's Thesis, Semyung University.
  3. Han, S.D., Kwon, J.H., Choi, S.K., Lim, B.H., Yoon, J.H. (1997). An experimental study on the manufacturing and application of high-workable and normal-strength concrete, Journal of the Architectural Institute of Korea, 17(1), 699-701 [in Korean].
  4. Lee, K.S. (2010). Effects of Mixing Parameters on the Flowing Behavior in High Flowing Concrete, Master's Thesis, Kyungpook National University.
  5. Lee, P.S., Kwon, K.J., Kim, S.M. (2004). The comparative experimental study of short and long-term behavior of the blended high-fluidity cement concrete and existing nuclear power plant structural concrete, Journal of the Korea Institute for Structural Maintenance and Inspection, 8(4), 195-202 [in Korean].
  6. Machoka, C.S. (1993). Report of superfluid concrete research committee(I), Japan Concrete Institute, 31(3), 79-82 [in Japanese].
  7. Okamura, H. (1986). Expectations for New Concrete Materials, Cement Concrete, 475 [in Japanese].
  8. Ozawa, K., Maekawa, K., Okamura, H. (1992). Development of the high performance concrete, Journal of the Faculty of Engineering, Tokyo University, Series B, 41(3), 381-439.
  9. Rols, S., Ambroise, J., Pera, J. (1999). Effects of different viscosity agents on the properties of self-leveling concrete, Cement and Concrete Research, 29(2), 261-266. https://doi.org/10.1016/S0008-8846(98)00095-7
  10. Seo, I. (2010). Study on the Evaluation of Pumpability and Fluidity of Concrete using Rheological Parameters, Master's Thesis, Hanyang University.
  11. Shadkama, H.R., Dadsetan, S., Tadayon, M., Sanchez, L.F.M., Zakeria, J.A. (2017). An investigation of the effects of limestone powder and viscosity modifying agent in durability related parameters of self-consolidating concrete(SCC), Construction and Building Materials, 156(15), 152-160. https://doi.org/10.1016/j.conbuildmat.2017.08.165
  12. Shin, H.C., Park, Y.S., Cho, S.H., Choi, H.Y., Kim, G.Y., Kim, M.H. (1997). A study on the evaluation method of fluidity of high flowing concrete, Journal of the Architectural Institute of Korea Conference, 17(1), 707-709 [in Korean].
  13. Wallevik, O., Wallevik, J. (2011). Rheology as a tool in concrete science: the use of rheographs and workability boxes, Cement and Concrete Research, 41(12) 1279-1288. https://doi.org/10.1016/j.cemconres.2011.01.009
  14. Yamada, K., Takahashi, T., Hanehara, S., Matushisa, M. (2000). Effects of the chemical structure on the properties of polycarboxylate-type superplasticizer, Cement and Concrete Research, 30(2), 197-207. https://doi.org/10.1016/S0008-8846(99)00230-6