Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Effects of Chemical Admixture on the Quality Characteristics of Grout for Prestressed Concrete

화학 혼화제가 PSC용 그라우트 품질 특성에 미치는 영향

  • Received : 2017.03.03
  • Accepted : 2017.03.25
  • Published : 2017.03.30
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Abstract

The study investigates the effects of the content and using method of chemical admixtures such as superplasticizer and viscosity modifying admixture on the fluidity, bleeding ratio, volumetric change and compressive strength of the grout in order to provide basic data for the development of high-quality grout for prestressed concrete. It appeared that the combination of superplasticizer and viscosity modifying admixture decreased the fluidity of grout with small content of superplasticizer. On the contrary, Grout used more than 0.1% of superplasticizer appeared to have significant effect on the improvement of the fluidity. On the other hand, bleeding of grout reduced according to increasing the content of viscosity modifying admixture. Superplasticizer with less than 0.05% had practically no effect on the reduction of bleeding, whereas superplasticizer with more than 0.1% appear to have significant effect on the reduction of bleeding. Also the combination of superplasticizer with 0.15% and viscosity modifying admixture with 0.15% resulted in satisfactory fluidity accompanied with fair reduction of bleeding and shrinkage of the grout.

본 연구에서는 프리스트레스트 콘크리트용 고품질 그라우트를 개발하기 위한 기초 자료로 활용하기 위해 그라우트의 화학 혼화제로 고성능 감수제와 증점제의 양과 사용방법이 유동성, 블리딩률, 체적변화 및 압축강도에 미치는 영향에 대해 검토하였다. 증점제와 고성능 감수제가 유동성에 미치는 영향에 대해 검토한 결과, 증점제와 고성능 감수제를 조합사용한 경우에는 고성능 감수제의 사용량이 너무 적으면 응집현상이 발생하여 유동성이 저하되나, 고성능 감수제 사용량 0.1% 이상부터 유동성이 크게 향상되는 것으로 나타났다. 증점제의 사용량이 증가할수록 블리딩률이 감소하며, 고성능 감수제는 0.05%까지 블리딩률이 증가하나, 0.1%부터 블리딩률이 감소하는 것으로 나타났다. 또한 고성능 감수제와 증점제를 각각 0.15%를 조합한 그라우트의 배합이 유하시간, 플로우, 블리딩 및 체적변화 측면에서 가장 양호한 것으로 분석되었다.

Keywords

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