DOI QR코드

DOI QR Code

Properties and Mock-up Test of Lightweight Foamed Concrete Based on Blast Furnace Slag by Crack Reducing Admixture

팽창성 균열저감제를 이용한 고로슬래그 미분말 기반 경량기포 콘크리트의 특성 및 목업실험

  • Received : 2017.09.22
  • Accepted : 2017.10.12
  • Published : 2017.12.20

Abstract

This study is to develop a high quality lightweight foamed concrete that can be applied in the field using EXFG by cracking reducing agent combined with FGD and ALS. First, to increase the volume of foam, the flow and density of the mixture was increased and decreased, respectively. At this time, the effect of substitution ratio of EXFG on fluidity was negligible. The fraction of foam was the highest at EXFG 1%, and the settlement was found to be prevented by the expansion reaction at EXFG 1%. At this time, the ratio of foam was 65%. In the compressive strength, the strengths were similar or decreased when the substitution ratio of EXFG was more than 1%. The apparent density satisfied the KS 0.5 type at the bubble contents was 65%. In case of EXFG substitution, dry shrinkage was decreased by about 10%. As the substitution ratio of EXFG increased, the thermal conductivity increased proportionally.

본 연구는 EXFG를 활용하여 실제 현장 적용이 가능한 고품질의 경량기포콘크리트를 개발하고자 하였는데, 그 결과를 요약하면 다음과 같다. 먼저, 기포혼입율이 증가할수록 플로치도 증가하였으며, 반대로 기포슬러리 밀도는 감소하는 것으로 나타났다. 이때, EXFG의 치환율이 유동성에 미치는 영향은 미미한 것으로 나타났다. 기포율은 EXFG 1%에서 가장 높은 기포율을 나타냈으며, 침하깊이 역시 EXFG 1% 치환 시 팽창반응에 의해 침하가 방지되는 것으로 나타났다. 이때 기포혼입율은 65%가 적정한 것으로 나타났다. 압축강도의 경우 EXFG의 치환율이 1% 이상일 때 강도는 유사하거나 오히려 감소하는 경향을 나타냈으며, 겉보기 밀도는 기포혼입율 65%에서 KS 0.5품 기준을 만족하였다. 건초수축길이변화율의 경우 EXFG를 치환한 경우 이를 사용하지 않는 배합 대비 건조수축일이변화율이 약 10% 이상 감소하는 것으로 나타났으며, EXFG의 치환율이 증가 할수록 열전도율도 비례하게 높아지는 것으로 나타났다. 한편, Mock-up 실험에서 균열발생의 경우 EXFG-1의 경우 기존기술 및 OPC 배합대비 약 50% 이상 균열이 저감되는 효과를 나타냈다.

Keywords

References

  1. Kim HS. Physical properties of lightweight foamed concrete according to lightweight aggregate types and foaming agent types. Journal of the Korea Concrete Institute. 2016 Aug;28(4):435-44. https://doi.org/10.4334/JKCI.2016.28.4.435
  2. Kim C. Reduction of floor impact sound and research subjects. Journal of the Korea institute of Building construction. 2003 Jun;3(3):43-7. https://doi.org/10.5345/JKIC.2003.3.3.043
  3. Yim G. Preparation of lightweight aerated concrete and characteristic analysis of foaming agent. Journal of Engineering Paichai University Korea. 2006 Mar;8(1):31-50.
  4. Han JS. An improvement method on the using probleme of the ground granulate blast-furnace slag as a concrete admixture in ready-mixed concrete plant. Journal of Architectural Institute of Korea. 2003 Mar;15(2):6-7.
  5. Kim MS. Effect of changes of bubble-based leavening agent and bubble mixing ratio on quality of lightweight concrete. Journal of the Korea institute of Building construction. 2016 May;16(1):189-90.
  6. Han CG. Quality of high volume blast furnace slag mortar depending on desulfurization gypsum treating methods and fine aggregate type. Journal of the Korea Recycled Construction Resources Institute. 2016 Jun;4(2):157-64. https://doi.org/10.14190/JRCR.2016.4.2.157