• Title/Summary/Keyword: Polymer cement

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Properties of Adhesion Tension of Polymer Cement Slurry for Coated Reinforcing Bar (철근 도장용 폴리머 시멘트 슬러리의 부착 특성)

  • 김현기;이철웅;장성주;김완기;소양섭
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.04a
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    • pp.343-348
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    • 2000
  • The purpose of this study is to clarify properties adhesive strength of polymer-cement slurry for coated reinforcing bars. The epoxy coating material is superior to performance of anti-corrosion but lately age adhesive strength between concrete raise to structural problems. However, polymer dispersion with excellent performance of elasticity and adhesion can solve this problems. From the test results. adhesion of steel with polymer cement slurry using St/BA emulsion is show excellent without concerned coating thickness, and polymer cement slurry using St/BA emulsion is show adhesion in tension 1.2~2.2MPa at polymer cement ratio 50% of more.

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Enhanced Durability Performance of Polymer Modified Cement Composites for Concrete Repair Under Combined Aging Conditions (복합열화 환경을 받는 콘크리트 시설물을 위한 보수용 폴리머 시멘트 복합체의 내구성능 향상에 관한 연구)

  • Won, Jong-Pil;Park, Chan-Gi
    • Journal of The Korean Society of Agricultural Engineers
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    • v.47 no.6
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    • pp.27-34
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    • 2005
  • The purpose of this study is to improve the durability performance of polymer modified cement composites for repair of concrete under combined aging conditions. The experimental procedure was divided into three parts. First, the replacement level of mineral admixtures in polymer modified cement composites were determined in an experimental study based on a Box Behnken design. Second, the flow value, compressive strength and chloride permeability test of sixteen types of mixtures were conducted. Test results show that the polymer modified cement composites were effected on the improvement of the compressive strength and permeability performance. Third, the effects on the replacement level of silica fume mixture was evaluated by the compressive strength, chloride permeability, chemical resistance and repeated freezing and thawing cycles test. They demonstrated that the polymer modified cement composites using mixture of silica fume, fly ash, and blast furnace slag improved the durability performance.

An Experimental Study on Properties of Polymer Cement Concrete with a Kind of Admixtures (혼화제 종류에 따른 폴리머 시멘트 콘크리트의 특성에 관한 실험적 연구)

  • Chang, Cheol-In;Yoo, Deok-Ryong;Yum, Hwan-Seok
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.8 no.1
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    • pp.121-128
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    • 2004
  • This study aims to attain the basic data needed for the adaptation and application of polymer cement concrete as a new construction material by reviewing the various physical characteristics of polymer cement concrete following the changes in polymer type. The research found that cement concrete mixed with polymer, while it had some variation, had excellent qualities in all of compressive strength, tensile strength, water absorption, weight reducing ratio, and resistance of freezing and thawing.

Exploring the Flexural Bond Strength of Polymer-Cement Composition in Crack Repair Applications (균열 보수용 폴리머 시멘트 복합체의 휨접착강도에 관한 연구)

  • Jo, Young-Kug
    • Journal of the Korea Institute of Building Construction
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    • v.24 no.1
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    • pp.23-34
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    • 2024
  • This research aims to assess the flexural bonding efficacy of polymer-cement composites(PCCs) in mending cracks within reinforced concrete(RC) structures. The study involved infilling PCCs into cement mortar cracks of varying dimensions, followed by evaluations of enhancements in flexural adhesion and strength. The findings indicate that the flexural bond performance of PCCs in crack repair is influenced by the cement type, polymer dispersion, and the polymer-to-binder ratio. Specifically, the use of ultra-high early strength cement combined with silica fume resulted in an up to 19.0% improvement in flexural bond strength compared to the application of ordinary Portland cement with silica fume. It was observed that the augmentation in flexural strength of cement mortar filled with PCCs was significantly more dependent on the depth of the crack rather than the width. Furthermore, PCCs not only acted as repair agents but also as reinforcement materials, enhancing the flexural strength to a certain extent. Consequently, this study concludes that PCCs formulated with ultra-high early strength cement, various polymer dispersions, silica fume, and a high polymer-to-binder ratio ranging from 60% to 80% are highly effective as maintenance materials for crack filling in practical settings.

Drying Shrinkage and Strength Properties of Polymer-Modified Mortars Using Redispersible Polymer Powder (재유화형 분말수지 출입 폴리머 시멘트 모르타르의 건조수축 및 강도특성)

  • Yeon, Kyu-Seok;Joo, Myung-Ki;Lee, Hyun-Jong;Jin, Xing-Qi;Lee, Chi-Won
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.1
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    • pp.51-60
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    • 2006
  • This study was conducted to investigate experimentally the drying shrinkage and the strength properties of redispersible SBR and PAE powder-modified mortars. Polymer-cement ratio, content of shrinkage-reducing agent and antifoamer content were manipulated as the experimental variables. The peculiarity of this study is to obtain a high early-age strength by using the portland cement and alumina cement with the ratio of 8 : 2. Until 7 days of age, the drying shrinkage remarkably increased up to $1\~2\times10^{-4}$, while it tended to decrease as the ratio of polymer to cement ratio and the content of shrinkage-reducing agent increased. Polymer-cement ratio was effective in improving the flexural, tensile and adhesive strengths: As the ratio increased, the strengths correspondingly increased. The flexural strength was in the range of $7\~11$ MPa, the tensile strength was $3.5\~5$ MPa and the adhesive strength was $1.2\~3.9$ MPa. On the other hand, the compressive strength tended to decrease as the polymer-cement ratio increased, and it was in the range of $23\~39$ MPa. All strengths, flexural, tensile, adhesive and compressive strengths, decreased as the content of powder shrinkage-reducing agent increased. It turned out that the polymer-cement ratio influenced more on the behavior of drying shrinkage and the properties of strength than the powder shrinkage-reducing agent did.

Basic Properties of Polymer Cement Mortar with EVA Emulsion and Admixtures (EVA 에멀젼과 혼화재를 사용한 폴리머 시멘트 모르타르의 기초적 성질)

  • Jo, Young-Kug
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.6
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    • pp.53-60
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    • 2019
  • The purpose of this study is to evaluate the degree of improvement in strengths by mixing blast-furnace slag and fly ash in polymer cement mortar(PCM). The test specimens are prepared with EVA polymer dispersion, two types of Admixtures (blast-furnace slag and fly ash), five kinds of polymer-cement ratios (0, 5, 10, 15 and 20%), and six kinds of admixtures (0, 3, 5, 10, 15 and 20%). Plain cement mortar is also made for comparison. From the test results, the flowing of PCM is greatly improved with the mixing of the admixtures, and strengths of PCM compared to ordinary cement mortar are also improved due to a decrease in water cement ratio. In addition, the strength characteristics of PCM by admixtures are greatly improved in flexural strength with fly ash compared to other strengths. It is apparent that the optimum mix proportions with polymer-cement ratio of 10% or more, admixture contents 5 to 10% of flay ash for flexural strength improvement of EVA-cement mortar are recommended in this study.

Drying Shrinkage and Strength Properties of Ultrarapid-Hardening Polymer-Modified Mortar Using Redispersible Polymer Powder (재유화형 분말수지를 혼입한 초속경 폴리머시멘트 모르타르의 건조수축 및 강도특성)

  • Lee, Youn-Su;Joo, Myung-Ki
    • Journal of the Korea Concrete Institute
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    • v.15 no.3
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    • pp.409-416
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    • 2003
  • The effects of polymer-cement ratio, antifoamer content and shrinkage-reducing agent content on the air content, setting time, drying shrinkage and strength of polymer-modified mortars using redispersible polymer powder are examined. As a result, the air content of the polymer-modified mortars using redispersible polymer powder tend to decrease with increasing polymer-cement ratio and antifoamer content. Regardless of the antifoamer content, the setting time of the polymer-modified mortars using redispersible polymer powder tend to delayed with increasing polymer-cement ratio. Irrespective of the antifoamer content, the drying shrinkage of the polymer-modified mortars using redispersible polymer powder tend to decrease with increasing polymer-cement ratio and shrinkage-reducing agent content. Regardless of the antifoamer content, the flexural and tensile strengths of the ultrarapid-hardening polymer-modified mortars using redispersible polymer powder tend to increase with increasing polymer-cement ratio, and tend to decrease with increasing shrinkage-reducing agent content. However, the compressive strength of the ultrarapid-hardening polymer-modified mortars using redispersible polymer powder decrease with increasing polymer-cement ratio and shrinkage-reducing agent content.

Flame Retardant Properties of Polymer Cement Mortar Mixed with Light-weight Materials for 3D Printing (3D 프린팅용 경량재료 혼입 폴리머 시멘트 모르타르의 난연특성)

  • Son, Bae-Geun;Song, Hun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.9 no.3
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    • pp.330-337
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    • 2021
  • 3D printing is not only at the fundamental study and small-scale level, but has recently been producing buildings that can be inhabited by people. Buildings require a lot of cost and labor to work on the form work, but if 3D printing is applied to the building, the construction industry is received attention from technologies using 3D printing as it can reduce the construction period and cost. 3D printing technology for buildings can be divided into structural and non-structural materials, of which 3D printing is applied to non-structural materials. Because 3D printing needs to be additive manufacturing, control such as curing speed and workability is needed. Since cement mortar has a large shrinkage due to evaporation of water, cement polymer dispersion is used to improve the hardening speed, workability, and adhesion strength. The addition of polymer dispersion to cement mortar improves the tensile strength and brittleness between the cement hydrate and the polymer film. Cement mortar using polymer materials can be additive manufacturing but it has limited height that can be additive manufacturing due to its high density. When light-weight materials are mixed with polymer cement mortar, the density of polymer cement mortar is lowered and the height of additive manufacturing, so it is essential to use light-weight materials. However, the use of EVA redispersible polymer powder and light-weight materials, additional damage such as cracks in cement mortar can occur at high temperatures such as fires. This study produced a test specimen incorporating light-weight materials and EVA redispersible polymer powder to produce exterior building materials using 3D printing, and examined flame resistance performance through water absorption rate, length change rate, and cone calorimeter test and non-flammable test. From the test result, the test specimen using silica sand and light-weight aggregate showed good flame resistance performance, and if the EVA redispersible polymer powder is applied below 5%, it shows good flame resistance performance.

Basic Properties of Polymer Cement Composites with Polymer Dispersions and Cement for Crack Repair (폴리머 디스퍼전과 시멘트로 만든 균열보수용 폴리머 시멘트 복합체의 기초적 성질)

  • Young-Kug Jo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.5
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    • pp.97-104
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    • 2023
  • The aim of this study was to produce polymer cement composites (PCCs) composed of polymer dispersion and cement as crack repair materials for RC structures, and to investigate their fundamental properties. The test mixtures for the study were based on EVA and SAE polymer dispersions, and the water-cement ratio was determined while varying the polymer-cement ratio(P/C) in four different levels (20%, 60%, 80%, and 100%) to achieve the desired viscosity of PCCs considering their fillability as crack repair materials. Additionally, silica fume was incorporated into P/C 80% and 100% specimens to enhance their stiffness. The basic properties of PCCs as crack repair materials, such as viscosity, flowability, fillability, tensile strength, elongation, and modulus of elasticity, were examined. The results showed that P/C depending on the type of polymer significantly affected the viscosity and flowability, and appropriate w/c ratios were needed to achieve the desired viscosity for the mixture design with consideration of fillability as crack repair materials for RC structures. All designed mixtures in this study exhibited excellent fillability. The tensile strength and elongation of PCCs satisfied the KS regulation for cement- polymer modified waterproofing coatings. The incorporation of silica fume improved the tensile strength and modulus of elasticity of PCCs. Depending on the type of polymer, mixtures using SAE showed better fundamental properties as crack repair materials for RC structures compared to those using EVA. In conclusion, SAE-based P/C 80% or 100% with the addition of up to 30% silica fume can be recommended as suitable mixtures for crack repair of RC structures.

Properties of Polymer-Modified Cement Mortars Using Methylmethacrylate - Butyl Acrylate Latexes (MMA/BA 합성 라텍스 혼입 폴리머 시멘트 모르타르의 성질)

  • 형원길;송해룡;김완기;소양섭
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.123-128
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    • 2001
  • The Purpose of this study is to clarify the effect of the monomer ratio on properties of the polymer-modified mortars using methyl methacrylate-butyl acrylate latexes, and to obtain basic data necessary to develop appropriate latexes for cement modifiers. This paper deals with the effect of the monomer ratio on the typical properties of polymer-modified mortars with methyl methacrylate-butyl acrylate latexes. The polymer latex-modified mortars are prepared with 5, 10, IS and 20% of polymer cement ratio respectively, and properties of modified mortars such as water absorption, compressive and flexural strengths, chloride-ion penetration depth are tested. The test results indicate that the monomer ratio is very important factors to characterize the strength properties of polymer-modified mortars, but the water absorption and chloride-ion penetration depth are influenced by polymer-cement ratio rather than monomer ratios.

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