• 산업기술연구
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• 제22권A호
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• pp.161-168
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• 2002

Latex modified concrete is governed by both cement hydration and polymer film formation processes in its binder phase. Such the reactions are expected to improve the polymer-cement co-matrixes themselves and the bond between the cement hydrates and aggregates, and to improve the properties of hardened latex-modified concrete. The purpose of this study was to study the strength and chemical resistance of Rapid-setting latex modified concrete(RSLMC) with the main experimental variables such as latex content(0, 5, 10, 15, 20%) and water-cement ratio(36, 38, 40%) at latex content 15%. Water absorption test was earned out to estimate water permeability resistance. Chemical resistance test was carried out to measure the weight change and to observe the appearance of RSLMC immersion in hydrochloric acid, sulfuric acid, and calcium choloride.

• 한국농공학회지
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• 제39권4호
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• pp.75-81
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• 1997

This study was performed to evaluate the engineering properties of surlightweight polymer concrete using synthetic lightweight aggregate. The following conclusions were drawn; 1. The unit weight was in the range of 0.849~0.969t/$m^3$, the unit weights of those concrete were decreased by 58 ~ 63% than that of the normal cement concrete. 2. The highest strength was achieved by $P_1$, and compressive strength was increased by 93% and bending strength by 364% than that of the normal cement concrete, respectively. 3. The ultrasonic pulse velocity was in the range of 2, 346~2, 702m/s, which was low compared to that of the normal cement concrete. 4. The dynamic modulus of elasticity was in the range of $1.561{\times} 10{^5}~1.916{\times} 10{^5}kgf/cm^2$, which was approximately 52~98% of that of the normal cement concrete. 5. The compressive and bending strength were increased with the increase of unit weight. But, the dynamic modulus of elasticity and ultrasonic pulse velocity were decreased with the increase of unit weight.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.51-57
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• 1996

The purpose of this study is to improve the properties by increasing of the adhesion strength of styrene-butadiene rubber(SBR) latex coated powdered rubber in cement mortar. SBR-modified mortar using powdered rubber is also tested as the same method. From the test results, the cement mortar using SBR latex coated powdered rubber have a good mechanical properties compared with that using uncoated powdered rubber. The mechanical properties of SBR-modified mortar using powdered rubber with polymer-cement ratios of 10% are also improved.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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• pp.67-73
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• 1992

Polymer-Impregnated Concrete(PIC) is a new polymer-concrete composite material which consist of basic cement concrete and polymer. The mechanical properties and behavior of PIC depend on the type of polymers and the impregnation techniques. In general, the polymer impregnation can improve the strength, durability and ductility of normal concrete. The objective of this study is to develop the analytical procedure for analyzing the structural responces of polymer-impregnated concrete beams with different polymer loading by using finite element method on the basis of experimental results.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.929-932
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• 2006

The effects of polymer-binder ratio, antifoamer content and shrinkage-reducing agent content on the setting time and drying shrinkage of high-fluidity polymer-modified pastes are examined. As a result, the setting time of the high-fluidity polymer-modified pastes tends to delayed with increasing polymer-binder ratio. Irrespective of the antifoamer content, the drying shrinkage of the high-fluidity polymer-modified pastes tend to decrease with increasing polymer-cement ratio and shrinkage-reducing agent content.

• 콘크리트학회지
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• 제4권1호
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• pp.107-118
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• 1992

본 연구는 고강도 고내구성이면서 신뢰성이 높은 폴리머 함침 탄소섬유보강 시멘트복합에의 개발 응용을 위한 여러 가지 특성을 검토하기 위하여, 복합체는 PAN계 및 Pitch계 탄소섬유, 조강포틀랜드 시멘트, Silica Powder 및 폴리머 함침재를 사용하여 제조하였고, 배합조건별, 재령별, 그리고 양생조건별로 역학적특성, 동결융해저항성 및 장기변형특성에 관한 실험연구를 행하였다. 연구결과, CFRC의 Flow값은 CF혼입율 증가에 따라 거의 직선적으로 저하하였고, 폴리머 함침 CFRC의 압축 인장 휨강도는 CF혼입율 증대에 따라 오토클래브 양생 및 기건양생의 경우에 비하여 현저히 증대하였으며, 또한 월등히 높은 강도를 나타내었다. 그리고, 인자응력-변형관계 및 휨응력-처짐관계는 기건양생 및 오토클래브 양생의 경우 연성적인 비선형을 나타낸 데 비하여 폴리머함침의 경우는 거의 직선적 으로 변화하였고, 동결융해저항성, 건조수촉변형특성 및 내크리프 특성도 다른 양생 방법의 경우에 비하여 크게 개선됨을 확인하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.749-752
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• 2008

본 연구는 섬유혼입 초속경 폴리머 시멘트 콘크리트의 강도 특성에 미치는 섬유 혼입량 의 영향을 검토한 것이다. 그 결과, 섬유혼입 초속경 폴리머 시멘트 콘크리트의 압축 및 휨강도는 섬유 혼입량이 증가함에 따라 증가하였다. 특히 폴리머-시멘트비 20%, 섬유 혼입량 0.12%인 콘크리트의 휨강도는 폴리머 미혼입 시멘트 콘크리트보다 2배 이상의 강도발현을 나타냈다. 이와 같은 강도발현은 폴리머 및 섬유의 높은 인장강도와 폴리머 및 섬유의 혼입에 의한 시멘트 수화물과 골재간의 접착성이 개선되었기 때문이라 판단된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1991년도 봄 학술발표회 논문집
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• pp.111-116
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• 1991

In order to discuss the mechanical properties of carbon fiber reinforced polymer impregnated cement composties with silica powder, experimental studies on CFRC were carried out. The types of fiber used which are in CFRC are PAN-based carbon fiber and Pitch-based carbon fiber. To examine the effects of types, length, contents of carbon fibers and matrices, their properties of fresh and hardened CFRC were tested. According to the test results, compressive, tensile flexural strength of polymer impregnated CFRC were remarkably increased more than that of air cured and autoclaved CFRC. Also, polymer impregnated CFRC were considerably effective in improving thoughness, freezing-thaw resistance and loss of shrinkage compared with air cured and autoclaved CFRC.

• 한국세라믹학회지
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• 제31권7호
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• pp.745-752
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• 1994

A polymer reinforced grouts using ordinary portland cement mortar and water soluble polymer{polyvinyl alcohol(PVA), styrene-butadiene rubbre(SBR), etylene-vinyl acetate copolymer(EVA)} were made. The mechanical properties of the hardened specimens were investigated through the observation of the microstructure and application of fracture mechanics. When the PVA, SBR and EVA was added with 1.5 wt% to the grouts, the compressive strength were about 54 MPa, 63 MPa and 68 MPa respectively, and the flexural strength was about 11 MPa, 12.8 MPa, and 13.6 MPa respectively, and Young's modulus was about 3.8 GPa, 4.4 GPa and 4.6 GPa respectively, and critical stress intensity was about 0.73 MNm-1.5, 0.85 MNm-1.5 and 0.9 MNm-1.5 respectively. It can be considered that the strength improvement of polymer mortar grouts may be due to the removal of macropores and the increase of various fracture toughness effects, such as grain bridging, frictional interlocking and polymer bridging.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.421-424
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• 2003

The purpose of this study is to clarify the effect of the emulsifier ratio on strength properties of the polymer-modified mortars using methylmethacrylate-ethyl acrylate(MMA/EA) latexes, and to obtain basic data necessary to develope appropriate latexes for cement modifiers. Polymer-modified mortars using MMA/EA latexes are prepared with various monomer ratios, and tested for air content, flexural and compressive strengths. From the test results, we knew that the water-cement ratio is decreased and the air content is increased with an increase in the amount of emulsifier. In general, the superior flexural and compressive strengths of polymer-modified mortars using MMA/EA latexes is obtained at a bound MMA content of 60 percent and a emulsifier ratio of 6 percent.