• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.165-168
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• 2005

This paper investigated the effect of W/C and the kinds of cement on the chloride invasion resistance of the offshore concrete. W/C set up 0.30, 0.35, 0.40 and The kinds of cement were used four(ordinary portland cement, ground granulated blast-furnace slag cement, belite cement, low heat portland cement). For the electrical migration test, NT BUILD 492's method was used to estimate the migration coefficient of chloride ion. As a result, the migration coefficients of chloride ion of concrete according to w/c were shown reducing with the w/c increasing, and according to kinds of cement were shown discrepancy in chloride invasion resistance. Especially blast-furnace slag cement was most low it. In the each cement, the compressive strength was shown related to the migration coefficient.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.126-129
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• 2000

To investigate the influence of kinds of cement on state of high-strength concrete, this study deals with the engineering properties of high-strength concrete used 4 kinds of ordinary portland cement. The result of this study be summarized as follows. 1) It appeared that the change in fluidity with time differ with kinds of cement. 2) The difference of setting time was seen over 3 hours according to kinds of cement. Therefore, it must be examined about used materials when high-strength concrete is manufactured in the construction field.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.599-602
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• 2005

In this research, the characteristics of the strength development and chloride attack resistance on the concrete using high early strength cement by steam curing temperature condition were studied. As a result, It is observed that the early strength(16hr) is increasing and the strength of 28 days is decreasing, according as the rising of the steam curing temperature without the kinds of base cement(OPC and high early strength cement). On the other hand, it is observed that the more the contents of the unit binder(base cement + GGBF) is abundant, the more the steam curing temperature can be reduced in case of the high early strength. Also, the chloride attack resistance is improved according as the amount of GGBF is increased with the kinds of base cement(OPC and high early strength cement).

• 대한치과보철학회지
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• 제42권1호
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• pp.41-48
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• 2004

Statement of problem : The Cement as well as restoration required esthetics for making natural color restoration. Purpose : The purpose of this research is to evaluate color stability of restoration intermediated by resin cement which is used for cementation of all ceramic crown. Material and method : After making Empress 2 ingot into the size of $10mm{\times}10mm{\times}1mm$ according to indication, it glazed and made 48 Empress 2 blocks. Three kinds of resin cement(Rely-X, Variolink 2, Choice) having same shade cemented between Empress 2 blocks and Ivory shade tiles and made 48 specimens in the thickness of $30{\mu}m$ and $80{\mu}m$. After measureing color difference using spectorphotomenter, the result of this study were as follows. Results : The color difference of resin cement used in experiment increased in the order Rely-X, Variolink 2. As the thickness of cement increases, the color difference of all kinds of cement found statistically sifnificant difference but, this result is clinically acceptable. Conclusion : More resarch would have to be done in order to decrease the color difference as cement's thickness.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.196-202
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• 1997

The objective of this study is characterize of Mortar and Concrete mae with Cement made with Cement containing Fly ash as an additive. Cement samples were prepared using tow kinds of Fly ash, which containing unburnt Carbon content 3.5% and 4.5%. Fly ash content in cement was in range 3wt% to 13wt%. In consequence of various experiments, these cement samples satisfied specification of Type I cement, and it is possible to use Fly ash as an additive to Type I cement in this content.

• 한국농공학회지
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• 제21권1호
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• pp.63-77
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• 1979

Six kinds of weathered granite soils whose degree of weathering and mineral compo- sitions are different, were tested in order to improve the soil-cement. by performing compression test, durability (freezing-thawing) test and mesurement of shrinkage are made. From result of the tests as mentioned above, the following conclusions are drawn. The unconfined compressive strength of seondary additives containing soil-cement mixtures and their resistance against freezeing-thawing are more increased and shrinkage is more decreased than soil-cement mixtures only in case opitimun quantity of additives are added to soil-cement mixtures, and according as types of soils.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.53-56
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• 2006

The objection of this study is to investigate the properties of cement mortar with the kinds and addition of expansive additives. 3 kinds of expansive additives produced in our country and 0, 5, 10, 15, 20% of ratio of addition rate are selected for this experiment. According to experimental results, flow of cement mortar with expansive additives is nearly same with flow of plain mortar and compressive strength, tensile strength, bend strength of cement mortar with expansive additives at 28 days is higher than that of plain mortar.

• 대한치과의사협회지
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• 제53권3호
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• pp.187-194
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• 2015

This paper reflects on the state of the art of two kinds of tooth hard tissue (enamel and dentin) bonding with resin cement. After presenting composition of resin cement, concepts of enamel bonding and resin bonding are addressed. Special attention is devoted to the concept and advantage of self-etching technique. Finally, recommended clinical performance regarding bonding to tooth with resin cement is summarized.

• 한국구조물진단유지관리공학회 논문집
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• 제23권6호
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• pp.53-60
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• 2019

이산화탄소 농도가 높은 도심지의 경우 탄산화로 인한 철근부식이 발생하기 쉬우며 이는 콘크리트 구조물의 내구수명을 감소시킨다. 콘크리트 구조물의 경우 다양한 구속조건을 가지며 항상 외부의 재하하중을 받고 있다. 도입된 응력수준은 이산화탄소와 같은 유해인자의 확산을 변화시키며 탄산화 깊이의 변동성을 야기한다. 본 연구에서는 응력재하수준에 따른 탄산화 변동성을 정량화하였으며, 이를 이용하여 탄산화 예측식을 도출하였다. 내구성 설계인자인 피복두께, 이산화탄소 확산계수, 탄산화 반응 수화물, 그리고 외부 이산화탄소 농도를 확률변수로 정의하였으며, MCS을 통하여 영향인자의 변동성에 따른 내구수명을 도출하였다. 또한 응력수준에 따라 변화하는 내구수명을 도출하였으며, 이를 결정론적인 방법의 결과와 비교하였다. 피복두께 및 내부 수화물 생성이 내구수명 변동성에 가장 큰 영향을 미쳤으며, 응력수준을 고려한 내구수명평가는 유지관리 우선순위 설정에 합리적으로 적용할 수 있다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.14-18
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• 1995

Since cement is one of materials of concrete and have an important effect upon physical properties of concrete, the quality characteristics of ordinary portland cement in domestic market are evaluated in this study. For this purpose, eight kinds of cement are selected and tested on the specific gravity, normal consistency, setting time, fincness, and compressive strength of cement ranged from 300kg/$\textrm{m}^3$ to 600kg/$\textrm{m}^3$ are tested for each kind of cement. As a result,ordinary portland cement in domestic market are satisfied with physical performance prescribed by KS L 5201(Portland Cement) and when unit weight of cement is 300~600kg/$\textrm{m}^3$, the maximum compressive strength of concrete cylinder is showed to be about 440-540kgf/$\textrm{cm}^2$.