• 콘크리트학회지
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• 제9권1호
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• pp.153-163
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• 1997

본 논문은 규사 분말을 치환한 모르터의 내화학성에 관한 실험적 연구이다. 모르터 시험체에 대하여 모르터의 내화학성능 개선용 혼화재로서 규사 분말의 활용성 및 콘크리트 시험체의 내화학적 특성에 관한 예측 모델로서의 모르터 모델의사용 가능성 등을 검토하였다. 그결과 다음과 같은 결론을 얻을 수 있었다. 모르터 모델의 콘크리트 내화학성 예측 모델로서 사용 가능성 검토 결과, 혼화재의 종류 및 치환량에 따른 내화학성 실험 결과가 콘크리트의 실험 결과와 유사하게 나타나므로 콘크리트 시험체의 내화학성 예측 모델로서 활용이 가능하리라 사료된다.

• 한국구조물진단유지관리공학회 논문집
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• 제23권7호
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• pp.113-119
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• 2019

해안매립지에 건설되는 구조물은 해수로부터 유입되는 염소 및 황산염 이온 등의 화학적 침식에 의한 영향을 복합적으로 받는다. 염해는 콘크리트 내부의 철근을 부식시켜 구조물의 성능을 저하시킨다. 또한, 하수처리시설에서는 내부에서 발생되는 황산염에 의해 콘크리트가 열화되는 문제점을 가진다. 따라서 본 연구에서는 해안매립지에 건설되는 하수처리구조물에 적용할 수 있는 혼합형 저발열시멘트의 특성 및 내화학성을 평가하였다. 실험결과, 모든 배합조건에서 목표슬럼프 및 공기량을 모두 만족하였다. 동일 배합조건에서 LHC사용시 OPC 보다 슬럼프는 증가되고, 공기량은 감소하는 경향을 나타내었다. 압축강도 시험결과, 초기재령에서는 OPC의 강도발현이 빨랐으며, 28일 이후 LHC가 OPC보다 높은 강도를 나타내었다. 염소이온침투저항성 평가결과, LHC-B의 경우 56일 재령에서, "매우낮음" 단계의 염소이온침투저항성을 나타내 LHC의 내염해성을 확인하였다. 내화학성 평가 결과, 에폭시 처리 하지 않은 경우 LHC를 적용한 경우, OPC보다 약 18%정도 내화학성이 개선되는 것으로 나타났으며, 콘크리트 표면에 에폭시 공법 적용시 강도보존율이 95% 이상 확보 가능한 것으로 확인되었다.

• International Journal of Concrete Structures and Materials
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• 제3권2호
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• pp.97-101
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• 2009

It has been known that acid-resistant concretes on the liquid glass basis have high porosity (up to 18${\sim}$20%), low strength and insufficient water resistance. Therefore they can not be used as materials for load-bearing structural elements. Significant increasing of silicate matrix strength and density was carried out by incorporation of special liquid organic alkali-soluble silicate additives, which block of superficial pores and reduces concrete shrinkage deformation. It was demonstrated that introduction of tetrafurfuryloxisilane additive sharply increases strength, durability and shock resistance of silicate polymer concrete in aggressive media. This effect is attributable to hardening of contacts between silicate binder gel globes and modification of alkaline component owing to "inoculation" of the furan radical. The optimal concrete composition with the increased strength, chemical resistance in the aggressive environments, density and crack resistance was obtained.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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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.

• 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.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.567-570
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• 2005

This study aims to verify the relationship between the penetration depth and chemical resistance, which can demonstrates the performance of the applied surface penetration sealers.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.183-188
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• 1996

The durability of concrete structures decrease due to deterioration of concrete when they are constructed in marine or pollutional environments. In this study, the mortar specimens made from the five different types of cement were immersed in artificial seawater and four kinds chemical solution, and were measured the change of compressive strength and weight. The results show that the longer the immersed days are, the more the compressive strength reduction is. It has been remarked that the resistance of slag cement and ground granulated blast-furnace slag is excellent in chemical attack.

• 한국농공학회논문집
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• 제55권6호
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• pp.11-17
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• 2013

This study was performed to evaluate the chlorine ion penetration resistance, chemical resistance and freezing and thawing resistance used ordinary portland cement, crushed coarse aggregate, crushed sand, river sand, fly ash, limestone powder, blast furance slag powder and superplasticizer to find optimum mix design of low carbon green concrete for structures. The performance of low carbon green concrete used fly ash, limestone powder and blast furnace slag powder were remarkably improved. This fact is expected to have economical effects in the manufacture of low carbon green concrete for offshore structures. Accordingly, the fly ash, limestone powder and blast furnace slag powder can be used for offshore structure materials.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.41-42
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• 2017

In this study, an investigation was made to study the chemical resistance performance of epoxy resin injection type leakage repair material used in the Korean construction market in accordance to the test method outlined in "ISO TS 16774, Part 2; Test Method for Chemical Resistance." This is a new standard document used for quality control method of injection type repair material used for leakage cracking of underground concrete structures. The results of this study can be expected to be utilized as reference data that can be used for quality improvement of the maintenance methods for future construction.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.625-630
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• 2002

The availability of natural aggregates has decreased in recent years due to depleting reserves. From the viewpoint of energy and resources saving, it may be advantageous to use the waste concrete as construction aggregates. The purpose of this study is to analyze petrographic and chemical properties of recycled aggregate, and to investigate the resistance of concrete to rapid freezing and thawing by using replacement ratios (0, 10, 20, 30, 40, 50, 60, 70, 100% ) of recycled aggregate.