• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.193-194
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• 2019

The purpose of this study is to design the basic mix proportions of antiwashout underwater polymer cement mortar as a repair material. The antiwashout underwater polymer cement mortars are prepared with various mix proportions using three type polymer dispersions without or with antifoamer. From the test results, the whole antiwashout underwater polymer cement mortars can be cast underwater without segregation like plain mortar. It is apparent that the flexural strength of antiwashout underwater SBR cement mortars with antifoamer at polymer- cement ratios of 5% and 10% is higher than that of plain mortar irregardless of a little low compressive strength.

• Computers and Concrete
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• v.12 no.3
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• pp.319-335
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• 2013

In this paper, the properties of the cement mortar modified with styrene acrylic ester copolymer were investigated. Expanded vermiculite as lightweight aggregate was used for making the polymer modified mortar test specimens. To study the effect of polymer-cement ratio and vermiculite-cement ratio on various properties, specimens were prepared by varying the polymer-cement and vermiculite-cement ratios. Tests of physical properties such as density, water absorption, thermal conductivity, three-point flexure and compressive tests were made on the specimens. Furthermore, a coupled thermal-structural finite element model of an entire corner wall was modelled in order to study the best material configuration. The wall is composed by a total of 132 bricks of $120{\times}242{\times}54$ size, joined by means of a contact-bonded model. The use of advanced numerical methods allows us to obtain the optimum material properties. Finally, comparisons of polymer-cement and vermiculite-cement ratios on physical properties are given and the most important conclusions are exposed.

• Polymer(Korea)
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• v.32 no.6
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• pp.603-609
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• 2008

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 (MMA/BA) latexes, and to obtain basic data necessary to develop appropriate latexes for cement modifiers. From the test results, the total pore volume of polymer-modified mortars using MMA/BA latexes is linearly reduced with an increase in the bound MMA content and increased in the polymer-cement ratio. In general, the superior flexural and compressive strength of polymer-modified mortars using MMA/BA latexes is obtained at a bound MMA content of 70 or 80 percent and a polymer-cement ratio of 15%. And, the water absorption and chloride ion penetration depth are greatly affected by the polymer-cement ratio rather than the bound MMA content.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.1011-1016
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• 2001

The purpose of this study is to find out the effect of polymer glass transition temperature on mechanical properties of polymer latex-modified mortars in comparison with ordinary cement mortar. The Polymer latex-modified mortars are prepared with 5, 10, 15 and 20% of polymer cement ratio respectively, and properties of modified mortars such as air content, compressive, flexural and tensile strengths are tested. The test results indicate that the types of polymer dispersion and the polymer-cement ratio are very important factors to characterize the properties of polymer-modified mortars, and also the glass transition temperature of polymer dispersions has an important effect on the performance of polymer-modified mortars. The modifying effects of two kinds of polymer dispersion, St/BA-1 and SBR, are evaluated.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.273-279
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• 2003

The purpose of this study is to clarify the effect of the monomer ratio on properties of the polymer-modified mortars using methylmethacrylate-butyl acrylate(MMA/BA) latexes, and to obtain basic data necessary to develop appropriate latexes for cement modifiers. From the test results, we knew that the pore volume of polymer-modified mortars using MMA/BA latexes at bound MMA contents of 60 and 70 percent is 7.5∼75nm and the fine pore volume is increased with an increase in the polymer-cement ratio. The total pore volume of polymer-modified mortars using MMA/BA latexes is linearly reduced with an increase in the bound MMA content and increased in the polymer-cement ratio. In general, the superior compressive strength of polymer-modified mortars using MMA/BA latexes is obtained at a bound MMA content of 70 percent and a polymer-cement ratio of 15%. And, the water absorption and chloride ion penetration depth are greatly affected by the polymer-cement ratio rather than the bound MMA content. The important factors affecting the properties of polymer-modified mortars using MMA/BA latexes polymerized with various monomer ratios are the variations of the pore size distribution with changing bound MMA content and the polymer-cement ratio.

• Journal of the Korea Institute of Building Construction
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• v.19 no.1
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• pp.47-57
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• 2019

The purpose of this study is to evaluate the improvement effect of adhesion in tension and flexure of polymer cement mortars that have widely used as a repair-reinforcement material in construction field according to adding of polymer dispersions depending on different three types test methods. From the test results, the adhesion performance is improved with a raise in polymer-cement ratio irrespective of the type of polymer. The maximums of A type adhesion in tension, B type adhesion in tension and adhesion in flexure show 1.90 times, 2.17 times and 1.83 times, respectively that of plain cement mortar. The relative strength ratios, B type adhesion in tension and adhesion in flexure of polymer cement mortars to tensile and flexural strengths of plain mortar respectively are in ranges of 50.1% to 101.7% and 73.8% to 132.9% compared to 46.9% of plain mortar. It is apparent that polymer cement mortars with EVA and polymer cement ratios of 10% to 15% are recommended considering its adhesion performance and cost as a repair-reinforcement material in construction field.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.350-355
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• 1998

Preplaced aggregate concrete in the building fields has recently been used in the partial repair works for damaged reinforced concrete structures, and polymer-modified mortars have been employed as grouting mortars for the preplaced aggregate concrete. The objective of this study is to clear the properties of polymer-modified grouting mortars. Polymer-modified mortars using a polystyrene acrylic(St/Ac) emulsion as grouting mortars for preplaced aggregate concrete are prepared with various mix proportions, and tested for flexural and compressive strengths, adhesion in tension. The flexural strength of emulsion-modified grouting mortars does not give much variation with increasing fly ash replacement for cement and sand-binder ratio. With increasing polymer-binder ratio, the flexural strength and adhesion in tension of St/Ac emulsion-modified grouting mortars increases, become nearly constant or reaches a maximum at a polymer-binder ratio of 5%. From the test results, St/Ac emulsion-modified grouting mortar with a polymer-binder ratio of 5%, a fly ash replacement of 10% for cement and sand-binder ratio of 1.0 is recommended as a grouting mortar for preplaced aggregate concrete.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.979-984
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• 1997

Test specimens of polymer-cement concrete composites were prepared using styrene-butadiene rubber(SBR) latex, ethylenevinyl acetate(EVA) and polyacrylic ester(PAE) emulsions as polymer dispersions in cement modified system at constant slump($10{\pm}0.5cm$), then compressive and flexural strengths water absorption, pore size distribution, and microstructures were investigated. Compressive and flexural strengths of these composites were remarkably improved with an increase of polymer-cement ratio. These composites had a desirable pore size distribution against frost damage due to a small capillary pore volume. Continuous polymer film was able to form in higher than 15% of polymer cement ratio.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.467-472
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• 2005

Asphalt emulsion is manufactured by the emulsification of asphalt, and is considered as an energy-saving, ecologically safe material because it does not need any heating processes with gas emission and fire hazard in its use. This study is concerned with evaluating the feasibility of the use of an asphalt emulsion as a poly-meric admixture. Asphalt-modified mortars using an experimentally manufactured asphalt emulsion were prepared with various polymer-cement ratios, and tested far the mechanical properties such as strengths and adhesion and the properties related to durability such as water absorption, permeation, carbonation and chloride ion penetration. As a result, the waterproofness, carbonation resistance and chloride ion penetration resistance of the asphalt-modified mortars were markedly improved with an increase in the polymer-cement ratio, but their compressive strength and adhesion to mortar substrates were reduced with increasing polymer-cement ratio. Therefore, it is recommended to control their polymer-cement ratio to be $10\%$ or lower in their practical applications. Further study to improve their compressive strength and adhesion is needed.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.11
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• pp.147-154
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• 2019

The purpose of this study is to evaluate the effect of admixtures as blast-furnace slag(BF) and fly ash(FA) on tensile and adhesive properties of polymer cement mortar(PCM) with EVA emulsion. The test specimens are prepared with five polymer-cement ratio(P/C) and five admixture contents, and tested for tensile strength and adhesion in tension. From the test results, the tensile strength and adhesion in tension could be improved by an appropriate combination of P/C and admixture contents. In particular, the maximum of tensile strength of PCM with P/C 10% and BF content of 10% is 4.70MPa which is about 1.55 times higher than that of plain mortar, and about 1.22 times that of PCM that does not contain any mixture. The ratio of adhesion in tension to tensile strength of PCM with admixtures averaged 55.8%. It is also apparent that admixture contents of 5% or 10% could be proposed for improvement of tensile strength and adhesion in tension of PCM.