• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.641-646
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• 1997

Polymer cement mortar which is used as material for aging concrete structures is generally mixed manually and applied on the job site. but, to secure the required quality of the mortar, pre-mixed polymer cement mortar is favored. This study was initiated to four different pre-mixed polymer cement mortars which are produced in Korea. The for pre-mixed mortars were selected and tested with respect to physical and mechanical properties an proved that their qualities were better than those of common cement concrete mortars.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.93-100
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• 2004

In recent years, it has widely been studied on the light-weight composites for the purpose of the large space and thermal insulation of building structures. The purpose of this study is to evaluate the properties of light-weight composites made by binders as cement, resin and polymer cement slurry. The concrete composites are prepared with various conditions such as polymer-cement ratio, void-filling ratio, type of resin, filler content and light-weight aggregate content, tested for thermal conductivity. From the test results, the thermal conductivity of concrete composites with the binder of cement tends to decrease with increasing polymer-cement ratio, and to increase with increasing void-filling ratio. The thermal conductivity of concrete composites with the binder of resin are markedly affected by the light-weight aggregate content, type of resin and filler content. The composites made by polymer-modified concrete and polymer cement slurry have a good thermal insulation property. From the this study, we can recommend the proper mix proportions for thermal insulation Panel or concrete. Expecially. the thermal conductivity of concrete composites made by polyurethane resin is almost the same as that of the conventional expanded polystyrene resin.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.695-698
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• 2004

Recently, the usage of polymer concrete mortar gathering an interest as a new construction material rapidly increases inside and outside of the country because it is an environment-friendly and endurable material. However, up to these days, the researches about the polymer composite have not been satisfactorily conducted. The polymer concrete is superior to the general cement materials in the properties of strength and durability while it is inferior in elastic modulus. Because that the members using the polymer concrete have therefore higher strength and ductility than the members of general cement concrete, an analysis equation of high-strength cement concrete can be referenced but it is not applied for the researches about the polymer concrete members. In this study, the flexural properties of T-shaped beam of the steel- and GFRP-reinforced polymer concrete are analyzed to examine the suggested analysis equation. Results of this experimental researches are to be used as the basic data in a structural design of the polymer concrete.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.2
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• pp.125-134
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• 1989

This study was conducted to investigate the flexural behaviour of sandwich constructions with cement concrete core and polymer concrete facings. Six different cross-sectional shapes using epoxy based polymer concrete facings were investigated. Some of the results from the static tests are given including the load-deflection responses, load-strain relationships, ultimate moment, and mode of failure. From the. results the following conclusions can be made. 1. The various strengths of polymer concrete were very high compared to the strengths for portland cement concrete, while modulus of elasticity assumed an aspect of contrast. 2. The thickness of core and facing exerted a great influence on the deflection and ultimate strenght of polymer concrete sandwich constructions. 3. The variation shape of deflection and strain depend on loading were a very close approximation to the straight line. The ultimate strain of polymer concrete at the end of tensile side were ranged from 625x10-6 to 766x10-6 and these values increased in proportion to the decrease of thickness of core and facings. 4. The ultimate moments of polymer sandwich constructions were 3 to 4 times that of cement concrete constructions which was transformed same section. It should he noted that polymer concrete have an effect on the reinforcement of weak constructions. 5. Further tests are neede to investigate the shear strain of constructions, and thermal expansion, shrinkage and creep of cement and polymer concrete which were composite materials of sandwich constructions.

• 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.

• Magazine of the Korea Concrete Institute
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• v.8 no.5
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• pp.135-143
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• 1996

Diffusion of water in hardened cement concrete and mortar influences on the dry shrinkage. creep. modulus of' elasticity, etc. In general, water loss through drying process in polymer-modified concrete and mortar is small compared with that of unmodified concrete and mortar due to the films formed by polymer as cement modifieder. The purpose of this study is to investigate the diffusion process of water in the polymer-modified mortars. The polymer-modified mortars using three polymer dispersions and epoxy resin are prepared with various polymer-cement ratios, and water diffusion coefficient of polymer-modified mortars according to inside water content is calculated. From the test results, the water diffusion coefficient of polymer modified mortars i s smaller than that of unmodified mortars and decreases with increasing polymer cement ratio.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.333-338
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• 2000

At present, reinforced concrete pipe has been widely used as drain pipe. However, many reinforced concrete pipe is exposed at deteriorated environment by the growth of a sulfur-oxidizing bacterium isolated from corroded concrete. The purpose of this study is to evaluate the effects of lining by polymer-modified mortar on the development in durability of reinforced concrete pipe. Polymer-modified mortars ate prepared with various polymer typer as cement modifier and polymer-cement ratio and rested for compressive and flexural strengths, adhesion in tension, acid resistance test, freezing and thawing test, and lining test of product in the field. From the rest results, it is apparent that polymer-modified mortars have good mechanical properties and durability as lining material. In practice, all polymers can be used as lining materials for reinforced concrete pip, and type of polymer, and polymer-cement ratio and curing conditions are controlled for good lining product.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1121-1126
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• 2000

The purpose of this study is to clarify chemical resistance of polymer-cement slurry coated reinforcing bars. Polymer cement slurry coated reinforcing bars were showed the good state to the bending resistance, impact resistance, adhesive strength, but exact data of the chemical resistance do not exist. Through the experimental, it is to certify chemical resistance of polymer cement slurry coated reinforcing bars. In this study, polymer cement slurry coated reinforcing bars are prepared with two types of polymer, polymer-cement ratios of 50%, 100%, 150%, coating thickness, curing periods of 3, 7, 28days, and tested for chemical resistance as KS(Korea Standard). From the test results, chemical resistance of polymer cement slurry coated reinforcing bars used by acrylic and St/BA emulsion were showed excellent without concerned polymer-cement ratios, curing period except for 1% aqueous solution $H_2SO_4$. But polymer cement coated reinforcing bar used by acrylic emulsion is inferior to aqueous solution NaOH.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.215-220
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• 2002

Epoxy-coated re-bar was partly used to the structures and put to practical use, but were not economical and appeared to have defects such as the diminishing of long term bond strength between concrete. The study of polymer cement slurry coated re-bar was started in order to complement the defect of epoxy coated re-bar, and ever since the basic properties appeared to be excellent. But, study of bond properties embedded in concrete specimens was insufficient until now. This study attempts to examine the possibility of improving the bond strength of polymer cement slurry coated re-bar between concrete specimens in accordance with ACI Code and KS Code through pull-out test of 150mm$\times$150mm$\times$150mm substrates with polymer cement slurry coated re-bar having polymer cement ratios of 50%, 75% and 100%, coating thickness 250${\mu}{\textrm}{m}$, 450 ${\mu}{\textrm}{m}$ and with curing ages of 3, 7 and 28 days. High strength concrete was designed having a compressive strength of 500kgf/cm2 as specified. Practical bond length ranges of 55 and 85mm were applied to each of specimen. The bond strength of polymer cement slurry coated re-bar using St/BA-1 and St/BA-2 was compared to that of plain re-bar. The results of this study showed that the bond strength of 55mm bond length was much higher than that of 85mm bond length.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.727-730
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• 2004

The purpose of this study is to evaluate the fundamental properties of fine type cement grouts with redispersible polymer powders. Cement grouts with redispersible polymer powders are prepared with various polymer-cement ratios, and tested. for flow, water absorption, drying shrinkage, flexural and compressive strengths. From the test results, flow of the cement grouts with EVA and Va/VeoVa polymer powers decreased with increasing elapsed time. Regardless of polymer type, the flexural strength of the cement grouts tends to increase with increase in polymer-cement ratio. The maximum compressive strengths of the cement grouts are obtained at a polymer-cement ratio of $5\%$.