• Title/Summary/Keyword: superplasticizer

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Study on the field application according to the early strength of the concrete admixed with polycarboxylate superplasticizer (폴리카본산계 고성능감수제를 이용한 콘크리트의 초기강도에 따른 현장적용성 연구)

  • Lee Jin Woo;Kim Kyung Min;Bae Yeoun Ki;Lee Jae Sam
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.05a
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    • pp.200-203
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    • 2004
  • In this study, it is examined the properties of flow and early strength of concrete according to superplasticizer. For this experiment, it is analyzed that the flow and strength properties according to the mixture factors, compared with naphthalene superplasticizer(normal & delay type) focused on polycarboxylate superplasticizer. (1) The slump loss of concrete used polycarboxylate superplasticizer showed $4\~8cm$, it is judged that slump loss according to the time lapse can be minimized. (2) The performance of polycarboxylate superplasticizer is about $70\%$ level of the normal naphthalene type, it is superior to the delay type, but the performance showed so lowly. The 28days, early strength didn't differ according to the kind of superplasticizer.

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A Study on the Experimental Study on Use Proper of Superplasticizer for Repair Mortar (보수 모르타르용 고성능 유동화제의 사용 적합성에 관한 실험적 연구)

  • Kim, Young-Sam;Song, Tae-Hyeob;Lee, Mun-Hwan;Lee, Sea-Hyun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.297-300
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    • 2006
  • Recently, To extend building's life, the use amount of repair mortar has been rapidly increased and naphthalenesulfonic and melanminesulfonic, polycarboxylic superplasticizer etc. are used for repair mortar in large numbers of construction site for efficient work. In this study, it was going to examine the use proper of superplasticizer for repair mortar through the hydrate setting time test and flow test with the mortar combination which replaced by alumina cement and added superplasticizer. As a result, the fluidity of the mortar replaced by alumina cement(10%) and added superplasticizer was dropped down and setting time was shortened. Especially this appearance was more increased on the mortar combination added ploycarboxylic and melanminesulfonic superplasticizer than naphthalensulfunic superplasticizer.

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Study on The Properties of The Concrete with Polycarboxylate Superplasticizer (폴리카본산계 고성능감수제를 사용한 콘크리트의 특성연구)

  • Oh, Byung-Hwan;Kim, Ki-Wan;Park, Dae-Gyun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.277-280
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    • 2004
  • Recently, as structure is more higher and bigger, we need high strength and high performance concrete. Therefore it is necessary superplasticizer for high strength and high performance concrete. In this study, it is examined the properties of flow, air content and strength of concrete with polycarboxylate superplasticizer in comparison with existing superplasticizer. First, The slump loss of concrete used polycarboxylate superplasticizer showed 2cm until 120 minutes. Second, The air content loss of concrete used polycarboxylate superplasticizer showed $1\%$ until 120 minutes. Third, It is possible to manufacture $1000kgf/cm^2$ strength concrete using polycarboxylate superplasticizer with $806kg/m^3$ cement content, $18\%$ water-binder ratio, $15\%$ silica fume, $10\%$ fly-ash content.

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Rheology Properties of Belite-rich Cement Mortar Added Blastfurnace Slag and Polycarbonate-based Superplasticizer (고로슬래그와 폴리카르본산계 유기 혼화제를 첨가한 Belite-rich Cement 모르타르 유동특성)

  • 송종택;송종택;조현태;황인수;박춘근
    • Journal of the Korean Ceramic Society
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    • v.37 no.2
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    • pp.145-151
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    • 2000
  • In order to investigate the rheological properties of belite-rich cement(BRC) added polycarbonate-based superplasticizer and blastfurnace slags which have different blaines at 4500, 6000 and 8000$\textrm{cm}^2$/g, the change of minislumps and mortar slumps are measured with time. The rheological properties improve as specific surface area of added slag decreases or amount of polycarbonate-based superplasticizer increases. The slump loss can be controlled effectively by the steric hinderance effect of polycarbonate-based superplasticizer. According to the results, when mix proportion of the mortar is 1.5% mass content of superplasticizer and 30% mass addition of blastfurnace slag which blaine is 4500$\textrm{cm}^2$/g, the best mortar slump can be achieved without any significant segregation of materials.

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Effects of silica fume, superplasticizer dosage and type of superplasticizer on the properties of normal and self-compacting concrete

  • Mazloom, Moosa;Soltani, Abolfazl;Karamloo, Mohammad;Hassanloo, Ahmad;Ranjbar, Asadollah
    • Advances in materials Research
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    • v.7 no.1
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    • pp.45-72
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    • 2018
  • In the present study, a special attention has been paid to the effects regarding the use of different superplasticizers in different dosages. To do so, 36 mixes of normal and self-compacting concrete with two water/binder ratios of 0.35 and 0.45, four different types of superplasticizer including melamine-formaldehyde, naphthalene-formaldehyde, carboxylic-ether and poly-carboxylate, four different superplasticizer/cement ratios of 0.4%, 0.8%, 1.2% and 1.6% and two silica fume/cement ratios of 0% and 10% have been cast. Moreover, the initial and final setting time of the pastes have been tested. For self-compacting mixes, flow time, slump flow, V-funnel, J-ring and L-box tests have been carried out as well as testing the compressive strength and rupture modulus. For normal concrete mixes,slump test has been conducted to assess the workability of the mix and then for each mix, the compressive strength and rupture modulus have been determined. The results indicate that in addition to the important role of superplasticizer type and dosage on fresh state properties of concrete, these parameters as well as the use of silica fume could affect the hardened state properties of the mixes. For instance, the mixes whose superplasticizer were poly-carboxylic-ether based showed better compressive and tensile strength than other mixes. Besides, the air contents showed robust dependency to the type of the superplasticizer. However, the use of silica fume decreased the air contents of the mixes.

The Execution and Estimation of Construction Cost of High Fluidity Concrete Applying Flowing Concrete Method (유동화공법에 의해 제조한 고유동 콘크리트의 시공 및 원가분석)

  • Han, Min-Cheol
    • Journal of the Korea Institute of Building Construction
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    • v.4 no.2
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    • pp.129-136
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    • 2004
  • High fluidity concrete(HFC) requires high dosage of superplasticizer to acquire sufficient fluidity, and high contents of fine powder and viscosity enhancing admixtures to resist segregation. The use of high amount of admixtures to make HFC at batcher plant in ready mixed concrete company is one of the reasons to raise the manufacturing cost of HFC. For this reason, new type of manufacturing method of HFC are described using both flowing concrete method and segregation reducing superplasticizer(SRS) in order to gain economical profit and offer the convenience for quality control.. As dosage of melamine based superplasticizer increases, it shows that fluidity and bleeding increase, while air contents and ratio of segregation resistance decrease. It also shows that addition of viscosity agent into superplasticizer reduce bleeding and improve segregation resistance of concrete. Dosage of AE agent into superplasticizer containing viscosity agent recovers loss of air contents during flowing procedure. Combination of proper contents of superplasticizer, viscosity agent and AE agent make possible to develope segregation reducing type superplasticizer. Compressive strength of high fluidity concrete applying flowing method with it is higher than that of base concrete. No differences of compressive strength between compacting methods are found. For the estimation of construction cost of high fluidity concreting using segregation reducing type superplasicizer, under same strength levels, although material cost of high fluidity concrete is somewhat higher than that of plain concrete due to segregation reducing type superplasticizer cost, labor cost and equipment cost of high fluidity concrete is cheaper than that of plain concrete. However, based on the strength differences, high fluidity concrete shows lower material cost, labor cost and equipment cost than that of plain concrete due to decreasing in size of member and re-bar caused by high strength development of concrete.

Development and Property Analysis of Segregation-Reducing Type Flowing Concrete Using the Viscosity Agent (증점제를 이용한 분리저감형 유동화 콘크리트의 개발 및 그 특성분석)

  • 한천구;강의영;오선교;반호용
    • Journal of the Korea Concrete Institute
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    • v.11 no.4
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    • pp.95-105
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    • 1999
  • When superplasticizer is added to manufacture flowing concrete, the base concrete usually needs the adjustment to assure the sufficient fines contained to obtain flowable consistency without excessive bleeding or segregation. However, this may not only increase the cost, but also cause inconvenience in producing the base concrete. In this paper, the experiments are performed on normal base concrete to achieve a segregation-reducing flowing concrete by adding superplasticizer mixed with viscosity agents and AE admixtures. Three kinds of superplasticizer and two kinds of viscosity agent are selected. According to the results, with regard to the performance and cost of the admixtures, melamine type superplasticizer combined with the PEO viscosity agent and AE admixtures at the ratio 1:0.28:0.001 can acquire good quality and reduce the cost in producing the flowing concrete. With proper addition of combined superplasticizer, even though water to cement ratios of the base concrete are different, the segregation-reducing flowing concrete could be also achieved without reproportioning of the base concrete. However, it would be more desirable if the superplasticizer could be adjusted, before it is put into the practical use in order not to cause some other problems, such as rapid rate of slump loss and retarding of setting time.

Synthesis and Application of Melamine-Type Superplasticizer at the Different Synthetic Conditions (멜라민계 고유동화제의 다양한 조건에서의 합성 및 응용)

  • Yoon Sung-Won;Shin Kyoung-Ho;Rho Jae-Seong
    • Journal of the Korea Concrete Institute
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    • v.17 no.5 s.89
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    • pp.811-818
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    • 2005
  • It is well known that the fluidity and the fluidity loss of fresh concrete are affected by the kind of organic admixtures. Organic admixture can improve the properties of concrete. Sulfonated Naphthalene-Formaldehyde(SNF) Superplasticizer is used representatively, but has a problem in fluidity loss. In this study, we synthesized the Sulfonated Melamine-Formaldehyde(SMF) superplasticizer at the various synthetic conditions and compared the physical properties with SMF superplasticizer. SW superplasticizer is synthesized with four synthetic steps. Step 1 is hydroxymethylation, Step. 2 is Sulfonation, Step. 3 is Polymerization and Step. 4 is Stabilization. Synthesis of SMF superplasticizer depends on pH, temperature and reaction time. In this reaction, we changed the mole ratio of melamine to formaldehyde at 1:3, 1:4, and the amount of acid catalyst at Step. 3. After application of SMF superplasticizer and its mixture with SNF superplasticizer to cement pastes and mortars, we measured the physical properties of them at the different dosages(0.5, 1.0, 1.5 wt%) to cement. All samples including superplasticizer showed higher compressive strengths and slump, smaller pore size and porosity than CEM

A Survey report on the Consumption Structure and Behavior of Domestic Superplasticizer (국내 고성능 감수제의 소비구조 및 형태에 관한 조사보고)

  • 최민수;이연우;김홍민;박영호;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1990.10a
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    • pp.141-144
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    • 1990
  • In recently, the interest of high strength and flowing concrete, to improve quality and workability of concrete, is gradually increased. In order to make high strength and flowing concrete, many processes may be considered, the water reducing technique using superplasticizer seems to be the most practical, but domestic superplsticizers are not widely used because of economical efficiency, low quality and lack of understanding in construction field. The purpose of this report is to analyze the consumption structure and behavior of domastic acmixtures containing superplasticizer, and to examine about, dessemination of superplasticizer.

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Determination of Optimal Mixture Proportion of Segregation Reducing Type Superplasticizer for High Fluidity Concrete (고유동 콘크리트용 분리저감형 유동화제의 최적배합비 결정)

  • 한천구;김성수;손성운
    • Journal of the Korea Concrete Institute
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    • v.14 no.3
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    • pp.275-282
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    • 2002
  • High fluidity concrete needs high dosage of superplasticizer to acquire sufficient fluidity and high contents of fine powder and viscosity agents to prevent segregation. But it requires high manufacturing cost and has difficult in quality control. Therefore, in this paper, determination of optimal mixture proportion of segregation type superplasticizer for high fluidity concrete and manufacturing high fluidity concrete by applying developed segregation reducing type superplasticizer are discussed using flowing concrete method. According to test results, as dosage of superplasticizer increases, it shows that fluidity and bleeding increase, while air contents and ratio of segregation resistance decrease. It also shows that adding viscosity agent into it reduce bleeding and improve segregation resistance. Dosage of AE agent into it containing viscosity agent recovers loss of air contents during flowing procedure. Combination of proper contents of superplasticizer, viscosity agent and AE agent make possible to develope segregation reducing type superplasticizer Compressive strength of high fluidity concrete applying flowing method with it is higher than that of base concrete. No differences of compressive strength between compacting methods are found.