Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Effect of Hollow Glass Powder on the Self-Compacting Concrete

유공 유리분말이 자기충전 콘크리트의 특성에 미치는 영향

  • Yoon, Seob (R&D Center, Sampyo Industry) ;
  • Han, Min-Cheol (Department of Architectural Engineering, Cheong ju University)
  • Received : 2018.02.13
  • Accepted : 2018.03.07
  • Published : 2018.04.20
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Abstract

In this study, compacting, passing performance, segregation resistance and rheological properties were tested to improve the stability of fresh concrete in the production and construction of self-compacting concrete (SCC) using hollow glass powder(GB). As a result, T50 reaching time was shortened up to amount of GB $2.0kg/m^3$. The compacting according to the amount of GB was improved by ball bearing effect of GB. However, T50 reaching time was slightly increased at $4.0kg/m^3$. In the case of passing performance, the result showed that plain was Class 1, GB $0.5{\sim}2.0kg/m^3$ was Class 0, GB $4.0kg/m^3$ was Class 1. Therefore, the passing performance was improved with 'No blocking' up to amount of GB $2.0kg/m^3$. Passing performance Block step (PJ) number by J-ring method was also best at GB $1.0kg/m^3$. In the case of segregation resistance according to the amount of GB, dynamic segregation resistance was increased compared to plain regardless of the amount of GB. And static segregation resistance showed 2.5% of segregation rate at GB $1.0kg/m^3$. Therefore, it was greatly improved compared to plain (12.5%). In the case of rheology property according to the amount of GB, plastic consistency by increasing of GB content didn't show big difference. However, yield stress by increasing of GB content was decreased with GB $1.0kg/m^3$. In conclusion, GB $1.0kg/m^3$ was effective for improvement of compacting, passing performance and yield stress. Also, it will be useful for stability of SCC by improving segregation.

본 연구는 자기충전 콘크리트의 생산 및 시공 시 굳지 않은 상태의 안정성을 향상시킬 목적으로 유공 유리분말(GB)를 혼입한 자기충전 콘크리트에 대하여 충전성, 통과성, 재료분리 저항성 및 레올로지 특성을 평가하였다. 실험결과, GB 혼입량에 따른 충전성은 GB의 볼베어링 효과로 인해 GB $2.0kg/m^3$까지 $T_{50}$ 도달시간이 Plain에 비하여 단축되어 충전성이 개선되는 것으로 나타났다. 단, GB $4.0kg/m^3$에서는 오히려 약간 증가되었다. 통과성의 경우에는 Plain 1등급, GB $0.5{\sim}2.0kg/m^3$ 0등급, GB $4.0kg/m^3$ 1등급으로 GB 혼입량 $2.0kg/m^3$까지 '보이는 차단 없음'으로 통과성이 개선되었다. J-ring에 의한 통과성 Block step($P_J$) 값도 GB $1.0kg/m^3$에서 가장 우수한 통과성을 나타내었다. GB 혼입에 따른 재료분리 저항성은 동적 재료분리 저항성은 Plain 보다 GB을 사용하게 되면 그 혼입량에 상관없이 동적 재료분리 저항성이 증가하였다. 정적 재료분리 저항성은 GB $1.0kg/m^3$에서 재료분리도 2.5%를 나타내어 Plain(12.5%) 대비 크게 개선되었다. GB 혼입에 따른 레올로지 특성은 GB 혼입량 증가에 따른 소성 점도는 큰 차이가 발생하지 않았으나 항복응력은 $1.0kg/m^3$까지 낮아졌다. 이상을 종합하면, GB를 $1.0kg/m^3$ 사용하게 되면 자기충전 콘크리트의 충전성, 통과성, 항복응력 개선에 효과적인 것으로 나타났다. 또한 재료분리 저항성을 증가시켜 자기충전 콘크리트의 안정성에 도움이 될 것으로 판단된다.

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References

  1. Construction Trend Briefing[Internet]. Seoul(Korea): Construction Economy Reserch Institute of Korea. 2017-[citied 2017 Nov. 636]. 1-13. Available from: http://www.cerik.re.kr/01/report.asp?page=3&startpage=1&totalpage=82&subject=&team=&pcls=3#
  2. Specification and Guidelines for Self-Compacting Concrete[Internet]. EFNARC, Association House, 99 West Street, Farnham, Surrey GU9 7EN, UK. 2002-[citied 2002 Feb 1]. Available from: http://www.efnarc.org/pdf/SandGforSCC.PDF
  3. Shen L, Jovein HB, Shen S, Li M. Effects of aggregate properties and concrete rheology on stability robustness of self-consolidating concrete. Journal of Materials in Civil Engineering. 2015 May;27(5):1-10.
  4. Kwan AKH, Ng IYT. Optimum superplasticiser dosage and aggregate proportions for SCC. Magazine of Concrete Research. 2009 May;61(4):281-92. https://doi.org/10.1680/macr.2008.00010
  5. Malhotra VM. The rheology of fresh concrete. Canadian Journal of Civil Engineering. 1984 Nov;11(1):128-9.
  6. American Society for Testing and Materials C 1610/C 1610/M:Test Method for static Segregation of Self-Consolidating Concrete Using Column Technique. Annual Book of ASTM Standard. 2009;04(2):856-9.