• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.257-262
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• 2000

The purpose of this study is grasping quality aggregate using Bottom Ash of Industrial Waste Incinerator, and is evaluating possibility of application as construction materials. Cement and Fly ash is used with binder of aggregates using bottom ash. It is tested for basic property and strength of artificial aggregates, and the results are compared with crushed stone and elution tests is done for environmental safety. In the results of tests, it is confirmed that basic property and strength are lowe than crushed stone but the aggregates have possibility of application as artificial lightweight aggregates. When it is manufactured with aggregates, it is sage environmentally because of protecting elution of harmful heavy metals.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.65-67
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• 2011

This research analyzed the mechanical properties of high strength concrete produced by limestone aggregate, and summarized the result as follows: Due to the property of unhardened concrete, slump flow value increased more or less according to the increase in LG replacement, but didn't show a big difference while clear tendency of air content couldn't be found. Due to the property of hardened concrete, there appeared an increase in the rate of compressive strength the more LG replacement increased, and the modulus of elasticity also showed a tendency similar to the increase rate of compressive strength.

• 한국환경보건학회지
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• 제33권4호
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• pp.325-337
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• 2007

The effect of seawater and air pollutants on the three-story stone pagodas on Gameunsa Temple Site have been studied in order to establish conservation basic plan. Also, an experimental study has been conducted to evaluate the effect of seawater salt and air pollutants on the weathering of granite. The results could be summarized as follows. Because the three-story stone pagodas on Gameunsa Temple Site are located outdoors, the external appearance has been largely deteriorated due to natural and artificial factors such as typhoon, wind, microorganisms, moisture, extreme change in temperature, air pollutants, and seawater, etc. When G.J fresh granite was dipped into the seawater, dissolution rate of three minerals (Mg, Ca, and K) are increased linearly until about 40 days and then increased abruptly. After seawater dipping experiments, the mineral compositions of the granite surface were lower then that of the G.J fresh granite but Poisson's ratio and absorption ratio were slightly increased. Therefore, from these results we can say that stone cultural properties could be weathered by seawater and air pollutants and it's considered being a meaningful experiment to study the conservation method of stone cultural properties from seawater.

• 한국건축시공학회지
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• 제6권1호
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• pp.101-107
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• 2006

While a Study with regard to the measurement on Concrete Strength and the Change of Drying Shrinkage in accordace with Content Ratio of Crushed Stone Powder, it is being analyzed as the result that the strength according to Content Ratio of crushed Stone Powder is somewhat lowering. Accordingly, it is the real situation that the Concrete mixed with Crushed Stone Powder is utilized for non-structural material, not for the structural material. Therefore, this Research willing to furnish the suitable utilizing scheme for construction site as well as practical life by means of conduct the experiment on both Concrete Pressure Strength according to mixture with Crushed Stone Powder and Elastic Modulus, it also presumes the optimum Elastic Modulus Equation after analysis of comparison with common concrete strength. As the result of the experiment, in case of the Content Ratio of Crushed Stone Powder is less than 5%, it did not display a big difference in its both strength and matter-property compare with common concrete. In case of Elastic Modulus, when the Pressure Strength is 50% and 40% respectively, the Elastic Modulus Equation accords very well with the provided condition of Quadratic function, and as the result of the Presumption on Elastic Modulus according to Content of Crushed Stone Powder, in case the Pressure Strength is 50%, Elastic Modulus Equation showed that Error Ratio of Cubic function is at degree of 0.0005%, in case the Pressure Strength is 40%, Elastic Modulus Equation was accorded well with the value of the experimental data likely as the Error Ratio of Cubic function is at the degree around 0.0034%, respectively.

• 한국지반환경공학회 논문집
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• 제13권8호
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• pp.45-55
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• 2012

본 연구는 폐석분의 성토재 활용에 대한 연구로서 폐석분, 화강풍화토, 그리고 폐석분과 화강풍화토의 혼합토에 대해 강도증진의 목적으로 단섬유를 보강한 경우의 강도 특성을 시험적으로 분석한 것이다. 폐석분, 화강풍화토 및 혼합토에 단섬유를 혼합한 경우 단섬유의 함량과 일축압축강도 증가비는 거의 선형적인 증가 경향을 보였으며, 화강풍화토에서 가장 큰 일축압축강도 증가비가 나타났고, 혼합토는 폐석분과 유사한 일축압축강도 증가비를 나타냈다. 전단강도 시험 결과 폐석분을 화강풍화토와 혼합한 혼합토의 경우 단섬유함량에 따른 점착력의 변화는 작았으나, 내부마찰각은 증가하는 추세를 보였으며, 단섬유 함유량 0.75%에서 21%의 내부마찰각 증가효과를 나타냈다. 폐석분 및 화강풍화토에 비교하여 상대적으로 강도정수가 크게 증가하는 경향을 보이고 있어 혼합토에서 단섬유의 보강효과를 기대할 수 있을 것으로 판단된다.

• 한국환경복원기술학회지
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• 제16권2호
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• pp.127-135
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• 2013

This study was carried out to verify the suitability of GRS(Glass-fiber Reinforced Slag) as natural type landscape stone according to the material property and structural safety performance standards. The structural safety performance of the GRS panel showed 12.4MPa and 16.2MPa each in flexural strength at 2 and 3% content of glass fiber while the flexural strength at 4 and 5% of glass fiber content showed 26.9MPa, and 30.2MPa, respectively, all satisfying the standards. In addition, air-dried gravity was found to be 1.82~1.89 in measuring range at 2~5% level of glass fiber content, satisfy the existing standards 1.8~2.3. In structural safety performance, the range of flexural strength consequent on glass fiber content was surveyed to be 12.8~30.2MPa, all satisfying the performance standards, while 10MPa and more while the compressive strength range was found to be 41.5~53.3MPa, all satisfying the performance standards, 40~60MPa. This study judged the suitability of only the items for a property of matter of landscape stone GRS by applying the natural-form landscape stone GFRC material standard, but in case an installation constructed with GRS material comes into existence later, there should be comprehensive performance guidelines through the research on durability, landscape performance and environmental and ecological performance.

• 보존과학회지
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• 제37권6호
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• pp.778-790
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• 2021

청주 비중리 석조여래삼존상 및 석조여래입상은 6세기 고구려 불상의 양식을 갖춘 중요한 국가지정문화재(보물)이다. 이들 석불상의 보존현황 파악 및 보존계획 수립을 위해 보존과학적 조사를 수행하였다. 석조여래삼존상 및 석조여래입상의 구성암석은 세립 내지 중립의 전형적인 흑운모화강암으로, 0.2(×10^-3 SI unit) 미만의 낮은 대자율 분포, 구성광물에서 서로 유사한 특성을 보여 동일한 기원의 암석으로 판단된다. 석조여래삼존상은 인근 노두의 암석과 광물 조성 및 입도, 전암대자율, 지구화학적 특성이 매우 유사하였으므로 성인적 동질성이 높은 것으로 해석된다. 한편 비중리 석조불상에서는 물리적, 화학적, 생물학적 요인이 복합적으로 작용하고 있는 것으로 확인되었다. 특히 석조여래삼존상과 여래입상 모두 전면에서 탈락이, 후면에서 균열과 박리박락이 우세한 경향을 보였다. 야외에 위치한 석조여래입상에서는 입상분해와 흑색조류가 발달하여 열악한 보존환경과 함께 풍화를 가속화하고 있다. 초음파속도를 이용한 비파괴 물성진단 결과, 석조여래삼존상과 여래입상의 풍화등급은 완전 풍화된 상태(CW)로 나타나 매우 낮은 물성을 지시하였다.

• 자원환경지질
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• 제32권2호
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• pp.203-208
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• 1999

The main objective of this study is to suggest a new assessment method of the influence of weathering due to salt crystallization on the engineering property of rock. For this purpose, various sources of salt and salt crystallization were investigated, and artificially accelerated weathering tests were carried out. In natural envionment, weathering rate is very slow and weathering process involves complex mechanisms. Therefore artificial weathering test is essential for systematic analysis. Arificial weathering test is defined as test which controls weathering rate and agents by controlling arificial environmental condition. In this study, salt crystallization test was selected among various artificial weathering test methods, for its important role in weathering. Change of various stone properties were detexted. The change of physical properties by salt crystallization were observed as follows : 72% in Brazilian tensile strength and 72% in Slake durability. These results explain the importance of salt crystallization in the mechanical behaviour and properties of stone.

• 지질공학
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• 제17권2호
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• pp.279-287
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• 2007

채석장으로부터 원석을 채취하여 건축석재 및 쇄석골재 등으로 가공하는 과정에서 원석의 약 60% 정도가 폐석이나 석분토로 손실되고 있다. 이 중에서 폐석의 일부만이 도로포장용 쇄석골재로 활용되고 있을 뿐 대부분의 석분토는 석재의 가공이나 파쇄공정에서 분말형태로 물에 혼입되어 슬러지탱크에 침전되게 된다. 이러한 석분토가 방류되거나 살포되면 지표나 지중의 공극들이 메워져 지표수의 지중침투, 지하수의 흐름, 공기의 소통 등이 원활하게 이루어지지 않아 생태계에 악영향을 끼칠 수도 있다. 현행 우리나라 폐기물관리법(2003)에 따르면 석분토가 사업장 내에서 발생되는 산업폐기물로 분류되고 있어 대부분을 지중에 매설하고 있는 실정이다. 따라서 석분토의 물성 및 공학특성을 개량하여 효율적 재활용방안의 수립이 필요하다. 이 연구에서는 국내 채석장에서 발생되는 석분토의 개량 및 재활용 가능성을 분석하기 위해 6개 채석장으로부터 시험용 석분토 및 원지반토를 채취한 후, 이를 일정한 비율의 배합비로 제작한 혼합토를 대상으로 여러 토질시험을 실시하였다. 시험결과를 토대로 도로용 재료로서 석분토의 개량 및 재활용 가능성을 검토하였다.

• 한국수학사학회지
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• 제15권2호
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• pp.161-168
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• 2002

We show that if the Stone-Cech compactification of $\textit{AX}$ and the minimal basically disconnected cove. of $\beta$Χ we homeomorphic and every real $\sigma$$Z(X)^#$-ultrafilter on X has the countable intersection property, then there is a covering map from $\nu$(ΛΧ) to $\nu$Χ and every real $\sigma$$Z(X)^#$-ultrafilter on Χ has the countable intersection property if and only if there is a homeomorphism from the Hewitt realcompactification of ΛΧ to the minimal basically disconnected space of $\nu$Χ.