• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.45-46
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• 2016

As coal fly ash emissions have increased due to additional constructions of domestic heat power plants, the amount of embedded reject ash (Rj henceforth) is increasing as well. Most Rj is embedded, so if it is used as an alternative admixture instead of cement, embedded quantities will decrease, leading to economic and environmentally positive effects. Therefore this study conducted an experiment to contemplate the usability of Rj ground in the Los Angeles abraser, and what effects ground Rj has on the engineering properties of high compressive strength mortar. The result was that as the number of grinding turns increased, liquidity, air quantity and intensity were improved, proving Rj a possible alternative admixture to cement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.54-55
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• 2016

Recently in the construction industry, industrial by-product admixtures like blast-furnace slag fine particles (BS henceforth) are being used as binding material, reducing the use of cement, and measures to reduce CO₂ emissions are being examined on various levels. However, the BS being used domestically varies depending on the origin of resources, and by circulating BS that is inappropriate to the KS standard, problems are occurring in terms of changes and declines in the quality of concrete which uses it. Therefore in this study the liquid densimeter principle was used to assess various BS fineness qualities; with 100 g/L fixed, a 1,000cc mass cylinder was most appropriate for assessing the quality of cement fineness.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.113-114
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• 2016

In this study, various fats and oils were soaked in low-strength mortar to experiment what kind of fats and oils had the worst effect on low-strength mortar; it went as follows. For rate of change in length of fat and oil soaking, there was an increase in the order of pig fat, bio-diesel, grape seed oil, and water; in the case of olive oil it was destroyed within 56 days. For rate of change in mass, there was an increase in the order of bio-diesel, water, pig fat, grape seed oil, and olive oil. For relative motion elastic coefficient, there was a decrease in the order of olive oil, grape seed oil, and water. On the whole, pig fat, bio-diesel, and olive oil were shown to have the worst effect on low-strength mortar.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.701-703
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• 2014

The intense noise generated by military aircraft hans a significant impact on ground crews and their families on airbase. For minimizing the impact of the aircraft noise on the airport, appropriate indoor noise standard is required. This paper studied to establish the indoor noise standard on the military airport. The aircraft noise was measured and analyzed the frequence characteristics. the remodeling of office for the noise mitigation was enforced to verify the appropriate internal noise standard and to select the method of reinforcement. The noise standard was classified three categories according to the dwelling, office and usage of building with flight train facilities and banishment in military airfield.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 1998년도 추계 학술논문발표회 논문집
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• pp.159-164
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• 1998

포틀랜트 시멘트가 개발되어 콘크리트에 응용됨으로서 콘크리트의 적용범위가 무한히 확대되고 있는 상황에서, 최근, 구조물이 고층화, 대형화, 특수화됨에 따라 건설재료인 콘크리트의 고품질화가 요구되고 있다. 이러한 고품질화의 최우선과제로 콘크리트의 고강도화에 관한 많은 연구가 국내외에서 이루어지고 있고, 실제 시공된 사례도 급속히 증가하고 있다. (중략)

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.38-39
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• 2016

In this research, the possibility of wasted refractory powder pulverized from refractory block as an expansive admixture and additional alkaline stimulant for class two and three blast furnace slag cements (BSC) was assessed with its high content of free CaO or free MgO. As the replacement ratios of wasted refractory powder and blast furnace slag were increased, flow and air content were decreased, while unit volume weight was increased under same conditions. Compressive strength of mortar was increased with increased replacement ratio of wasted refractory powder, especially, in the case of class three BSC, the highest compressive strength was obtained when wasted refractory powder was replaced 10 %.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.147-148
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• 2016

Generally, the vegetable oil contains glycerin esther and free fatty acid. When the vegetable oil reacts with concrete, the glycerin esther from oil induces saponification by reacting with and hydrolyzing calcium hydroxide from cement hydration. As a result of this saponification, it has been reported the expansion of concrete. although the free fatty acid from vegetable oil, as an acid, can decompose the concrete by producing soluble salt from calcium hydroxide or CSH, the hydration products of cement, there was no report on the harmful oil type for concrete. therefore, in this research, the property change of cement mortar incorporating fly ash was analyzed experimentally by immerging various types of vegetable oils.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1242-1247
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• 2000

Results from a study on the effect of the chemical agent on the flowing and setting properties of high flowing.high strength concrete using blast-furnace slag are presented in this paper. The flowing and setting properties of concrete are investigated by slump, slump-flow, flowing velocity, L-flow, velocity of V-funnel, L-spatial passability and setting time. In addition, kinds of chemical agent were composed of naphthalene type, of naphthalene and melamine and melamine type. The results indicate that dispersive capacity can be increased by naphthalene composition. Also, it shows that viscosity and early strength can be increased by melamine composition.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.75-76
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• 2017

In this study, it is speculated that the special admixture can be mixed with ERCO beforehand to prevent adsorption of cement and AE at the time of contamination together with water, and the change in the amount of special admixture preliminarily added to ERCO We will try to analyze the influence on normal strength mortar. As a result, the flow quantity, the air quantity, the compressive strength and the flexural strength were improved as the added amount of the special admixture was increased, and When the special admixture with the addition amount of ERCO 3% was added, the strength was rather lowered. Therefore, it was found that the optimum amount of special admixture added to ERCO was 2%.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.65-66
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• 2017

Early-frost damages easily take place in smaller and thinner walls and slabs. In case of slabs, it is difficult to visually determine the depth of early-frost damage. As such, the current study aims to determine the depth of early-frost damage caused to concrete structures due to bad curing in the winter. As a result, the study found that the depth of early-frost damages increased from the top as the atmospheric temperature on the concrete surface decreased. The changes in the color allowed the observer to easily identify the depth of early-frost damage with the naked eye. In particular, the color difference between potentially damaged parts and undamaged parts were the greatest around thirty minutes of drying after wetting.