레올로지 정수를 이용하여 21, 24MPa급 일반강도 콘크리트의 재료분리 경계를 판단하기 위한 기초연구 = A Fundamental Research on Determining Segregation Boundary using Rheological Parameters for 21 and 24MPa grade of Normal Strength Concrete

다국어 초록 (Multilingual Abstract)

The aim of the research is to provide the boundary conditions for segregation of normal strength grade and high fluidity concrete mixture (so called mid-fluidity concrete) with rheology parameters. Since the normal strength grade concrete mixture has a relatively high water-to-cement ratio and no SCMs, it is easy to be segregated when superplasticizer is added. Hence, to achieve the mid-fluidity concrete of normal strength grade and high fluidity, preventing segregation of the mixture is inevitable. In this research, using two superplasticizers with different solid concentrations, the flow behaviors and rheological behaviors were assessed by increasing fluidity until the segregation happened. According to the experiment in this research, an unusual behavior in rheology parameters was observed when the concrete mixture started to be segregated. From this results and report, it is expected to contribute on the definition of segregation with rheological test methods.

참고문헌 (Reference)

1 손배근, "일반강도 콘크리트의 효과적인 유동성 증진 및 품질안정성 확보를 위한 감수제 성능에 대한 연구" 한국건축시공학회 17 (17): 429-435, 2017

2 Wedding P, "Water Soluble Polymers : The Relationship Between Structure, Dispersing Action, and Rate of Cement Hydration" 2 : 68-75, 1986

3 Peter B, "Use of viscosity-modifying admixtures to enhance robustness of SCC" Curran Associates 566-571, 2008

4 Han CG, "Suggestion of segregation evaluation method based on evaluation index for segregation (EIS)" Korea Concrete Institute 923-926, 2008

5 Wallevik OH, "Rheology as a tool in concrete science: The use of rheographs and workability boxes" 41 (41): 1279-1288, 2011

6 Wallevik OH, "Rheology as a tool in concrete science : The use of rheographs and workability boxes" 14 (14): 1279-1288, 2011

7 Han CG, "Ready-mixed-concrete quality management" Kimundang 10-, 2010

8 Lee JH, "Performance evaluation of superplasticizers using a test mortar" 10 : 9-10, 2016

9 Han CG, "Manufacturing and properties analysis of semi-high-fluidity concrete using segregationreducing type superplasticizer" 16 (16): 59-67, 2000

10 Germann Instruments, Inc, "ICAR Rheometer"

11 Han CG, "Development and property analysis of segregation_reducing type flowig concrete using the viscosity agent" 11 (11): 95-105, 1999