• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.49.2-53
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• 2003

This paper reports the application of high strength concrete designed as 800kg/$cm^2$ on the columns and belt wall of Tower Palace III. The concrete should meet or exceed the requirements of slump of 23cm, ${\sigma}$18H of 100kg/$cm^2$, ${\sigma}$91th of 800kg/$cm^2$. The concrete mixings with 4 different domestic Silica fumes were investigated. Laboratory tests, the pilot productions of batcher plant and the full-scale mock up tests were performed As results of site application, all test results are satisfied with the requirements of columns and belt wall.

• 한국구조물진단유지관리공학회 논문집
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• 제2권2호
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• pp.209-217
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• 1998

Compared to normal-strength concrete, high-strength concrete has the lower lateral expansion capacity caused by the higher elastic modulus and the lower internal crack characteristic. Therefore, the effect of the lateral confining action of hoops appears slowly. Nevertheless, it has been reported that the strength and deformation capacity of high-strength concrete is improved by well-distributed hoops. Due to that argument, this investigation has been compared and analyzed by the experimental works on the deformation capacity and the confinement mechanism of high-strength concrete shear wall of the high-rise building reinforced by rectangular steel tubes and rectangular hoops at both edges. It is suggested that, using high-strength concrete($500kgf/cm^2$, $700kgf/cm^2$), hoops should be replaced with rectangular steel tubes in order to prevent closely spaced hoops at the edge of the shear wall.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.885-888
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• 2006

Nowaday, High strength concrete(HSC) has been mainly used in high rise building. HSC have superior property as well as improvement in durability compared with ordinary strength concrete. In spite of durability of HSC, explosive spalling in concrete front surface near the source of fire occurs serious problem in structural safety. Thus, this study is concerned with experimentally investigation fire resistance of the inorganic fire protection materials at high temperatures up to $800^{\circ}C$. From the test result, developed inorganic binder becomes general that with rising temperature the compressive strength of the material increases in tendency. Therefore, the results indicate that it is possible to fireproof panels, fire protection of materials, etc.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.239-242
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• 2009

As the high-rise building increase due to the gravitation of population to big cities recently, it requires high quality and high performance of Concrete. As a result, people are keenly interested in Meta-kaolin as new admixture favorable from an economic perspective, which has strength and endurance with admixture at the same level like Silica-fume. Accordingly, as to Meta-kaolin, this study was to set by three levels like domestic one, foreign one, and Silica-fume, the water-binding material ratio 25%, and four level substitute like 0, 10, 20, and 30(%) in order to compare and analyze the quality durability of high-concrete according to the substitute of Meta-kaolin applicable with replacement of Silica-fume. As a result of performing experiment it was found that when water-binding material ratio increases, resistance of neutralization, carbonation, salt damage and sulfate decrease, and when replacement ratio of mineral admixture increases, depth of accelerating carbonation gets greater. Also, the combination of SF and MK-B favored resistance to chloride ion penetration better than MK-A, and it was found that when replacement ratio of binding material increases, the resistance to sulphuric acid increases. Therefore, based on this study, it was understood that meta-kaolin is useable in replacement of silicafume.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.111-112
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• 2022

Lightweight aggregate is a porous material that has a lower density than natural aggregate and is a lightweight construction material. Lightweight Aggregate has a suitable purpose because it is effective in reducing the heavy unit mass in high-rise buildings. However, since lightweight aggregate has weak strength and high water absorption compared to natural aggregate, it is difficult to control the quality of concrete. Although lightweight aggregate has disadvantages such as high water absorption, it is expected that the demand for lightweight aggregate concrete will continue to use in the future because the advantage of being able to reduce the weight of concrete is greater. In this study, we conducted an experimantal study on the compressive strength property of cement matrix according to the type of lightweight aggregate.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.136-137
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• 2018

The properties of concrete produced by ready mixed concrete company in Busan were measured. Because the concrete was mixed with blast furnace slag and fly ash etc., the compressive, tensile strength and chloride ion diffusion coefficient were lower than OPC concrete even though the specified concrete strength was same. If the durability about salt attack were satisfied, the concrete of lower specified concrete strength would be adopted to concrete mixing design. FEM analysis was carried out to predict the life time expectancy.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.101-102
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• 2012

In this study, it was evaluated about hydration heat reduction under hot weather condition. Placement temperature set 25℃ and 35℃, For hydration heat reduction was applied such as FA and BFS. As a results, mixture of BFS70% is the most effective hydration temperature reduction.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.37-40
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• 2005

High Performance Concrete(HPC) has been widely used in high-rise building. The HPC has several benefits including high strength, high fluidity and high durability. However. spatting is susceptible to occur in HPC and HPC also tends to be deteriorated in the side of fire resistance performance at fire. This paper focuses on the analysis of the temperature history and residual compressive strength with finishing material, in order to protect HPC from sudden-high-temperature, which is one of the main reason spatting occurs. Test results show that spalling occurs in all specimens. The most serious spalling took placed in HPC covering fire enduring spray-on material, whose covering thickness is 20mm but temperature history indicates that fire enduring spray effectively protected HPC from fire for more than 2hours. In addition, residual compressive strength ratio of HPC using fire enduring paint was more than $90\%$ of original strength, thus minimizing spatting and indicating significant fire resistance performance.

• 한국건축시공학회지
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• 제10권3호
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• pp.113-120
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• 2010

본 연구에서는 실내 배합 실험을 통하여 150MPa 초고강도 콘크리트의 제반 물성을 평가한 후 150MPa 초고강도 콘크리트제조를 위한 최적 배합 조건을 제시하고자 하며 압축강도, 응력-변형률 관계, 탄성계수와 인장강도, 휨강도 등과 같은 기본적인 재료역학 특성을 평가하고자 한다. 이를 위하여 초고강도 콘크리트의 목표 물성으로 배합강도는 150MPa, 슬럼프 플로는 $700{\pm}50mm$를 목표로 정하여 57개의 배합을 실시하였으며, 각각의 배합조건에 따른 물성 및 역학특성을 검토하였다. 실험결과 초고강도 콘크리트는 보통의 고강도 콘크리트보다 매우 큰 점성을 가지므로 이러한 점성과 콘크리트 타설 및 작업성의 상관성을 고려하여 700~800mm 정도의 플로값을 확보하여야 할 것으로 판단되며, 재령 56일 압축강도를 100%로 할 때 3일은 64%, 7일은 70%, 28일은 약 95% 발현하였다. 150MPa 정도의 초고강도 콘크리트 제조를 위한 단위 시멘트량은 대략 1030~1150kg/$m^3$ 정도이며, 물-결합재비는 12~14%의 범위 내에서 적당하며, 잔골재율은 점성 및 작업성을 고려하여 30~35% 범위 내에서 결정될 수 있음을 확인하였다.

• 국제초고층학회논문집
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• 제8권3호
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• pp.161-167
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• 2019

Making full use of material strength, maintaining sufficient ductility of structural components, and ensuring simple and robust connections are crucial to the development of steel-concrete composite structures. The steel-tubed concrete structure uses thin-walled steel tube to provide confinement, so that the strength and ductility of the concrete core are improved. Meanwhile, the thin-walled steel tube is terminated at the beam-column joint to avoid the local buckling problem and simplify the connections between steel tube and RC members. A brief overview of the development of steel-tubed concrete structures is presented. Through the discussion on the structural behavior of steel-tubed concrete and the introduction of typical practical projects, the prospects for future research are highlighted.