• Fire Science and Engineering
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• v.24 no.4
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• pp.55-61
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• 2010

Fire resistance is very essential for all buildings to save peoples who live within buildings or use and to protect the properties when the buildings are covered with fire. The fire resistance were evaluated by loading or nonloading fire tests which are known very expensive and require lots of time. That causes the lacks of research activities and there are only small cases of fire resistance. The purposes of this paper are to analyze the temperature analysis for various structural elements such as columns and beams those are can be applied to buildings and to suggest the resonable fire protective thickness of concrete slab according to the required fire resistance time.

• Journal of the Korea Institute of Building Construction
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• v.16 no.3
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• pp.193-199
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• 2016

This study is a research about performance of fireproof board using industrial waste such as oyster shell and dry process bottom ash through the heating test and conclusions were obtained as follows. Test samples show back side temperatures as follows : in $300^{\circ}C$, $103.1{\sim}125.1^{\circ}C$, in $600^{\circ}C$, $201.1{\sim}210.1^{\circ}C$, in $900^{\circ}C$, $249.2{\sim}276.9^{\circ}C$. In the test, temperature increases of specimens of fireproof board are kept at certain temperatures hence it could be concluded that the specimens withstand high temperatures. According to the test, it could be concluded that fireproof board made by smaller particles shows better performance up to $600^{\circ}C$ while at higher temperatures, fireproof board made by bigger particles shows better performance. It is estimated that fireproof board made by particles of bigger size has more pore structure and it delays heat conduction.

• International Journal of Highway Engineering
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• v.4 no.1 s.11
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• pp.135-147
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• 2002

Application of the foamed asphalt techniques in recycling the waste asphalt shows that large quantify of waste asphalt(60$\sim$70% of the total mix) can be used comparing with hot mix asphalt techniques and also is environmentally safe. However, the constant quality of the recycling foamed asphalt mixtures is not readily achieved and can not be applied to the heavy traffic road due to the characteristics of the conventional foamed asphalt mixtures. The semi-hot technique that the RAP and the aggregate is heated below $100^{\circ}C$ is adopted in this study and expected to solve the problems of conventional foamed asphalt mixtures. This study presents the viability of the semi-hot foamed asphalt mixtures when using the RAP. The semi-hot recycling foamed mixtures are tested and evaluated in the laboratory. The test results including coating rates, creep tests, resilient modulus tests, indirect tensile tests and the Marshall stability tests showed significant improvement.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.3-5
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• 2018

유도 가열 (Induction Heating; IH) 기기는 빠른 가열 속도, 안전성, 청결성 등의 장점으로 산업계와 가정에서 널리 사용되고 있다. 하지만 기존 IH 기기는 낮은 저항을 갖는 비자성체 용기를 가열할 때 1차측 스위치에 높은 전류가 유도됨으로써 스위칭 손실과 전도 손실이 증가하고 스위치 정격 전류량을 초과하는 문제가 발생하였다. 본 논문에서는 용기 재질에 따른 임피던스 특성을 분석하여 비자성체 용기를 가열하기 위한 적절한 유도 가열용 직렬 공진형 컨버터의 새로운 스위칭 변조방식을 제안한다. 2 kW의 정격 전력을 가지는 유도 가열용 컨버터의 시작품을 사용하여 설계 방법론과 스위칭 변조 방식의 타당성과 성능을 검증하고자 한다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.05a
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• pp.112-115
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• 1993

복사관을 이용한 가열방식은 복사관내에서 연료를 연소시킬 때 얻어지는 열이 관을 통하여 복사됨으로서 피가열물을 가열하는 방식으로서 분위기제어가 필요한 열처리로 등에 널리 사용되고 있다. 본 연구에서는 연속 소둔설비용으로서 저 NOx화 및 복사관의 표면온도를 상대적으로 균일하게 가열시키는 특성을 가진 버너의 개발을 위한 것으로서 실기규모 연소실험을 수행하였다. 연소실험은 기존버너 및 편심노즐버너에 대해서 수행하였으며 특히 개발실험용 버너의 실험과정에서는 새로 고안된 버너의 성능평가로부터 최적화에 이르기까지의 종합적인 실험을 수행하였다. 개발실험에 의해 편심노즐을 특징으로 하는 2단연소식 복사관버너를 고안하였으며 시제품버너의 성능실험결과 기존버너보다 NOx방출량에서 30%의 감소를 보여주었으며 복사관에서의 온도의 균일성이 향상되었음을 확인하였다.

• Magazine of the Korea Concrete Institute
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• v.10 no.5
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• pp.109-115
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• 1998

철근콘크리트 구조물이 과소설계되어 있거나 과다 하중이 작용하게 되면 그 구조물의 구조성능을 파악하여 보수.보강을 시행하게 된다. 최근에 가장 맣이 사용되는 보수.보강 재료로는 특히 휨내력을 보강하는데 탄소섬유를 들 수 있다. 탄소섬유쉬트는 내열성과 내호염성에 있어서 회재가 발생할 경우 보강재료로서 충분한 성능을 가지고 있다. 그러나 이를 접착시키는데 사용되는 에폭시는 유기계 물질로서 화재시 유독가스가 발생하고 내열성능도 30$0^{\circ}C$정도에도 지탱하기 어려워 화재 발생이 가능한 구조물에 사용하기 어렵다. 이 연구에서는 무기계 폴리머 복합재료로 접착된 탄소섬유를 고온(약 800~100$0^{\circ}C$, 1시간)으로 가열한 후 가열된 섬유판의 인장, 휨 전단내력을 검토하여 내열성능을 파악하고 이 섬유쉬트로 보강한 철근콘크리트 부재의 휨 성능을 실험적으로 규명하여 화재의 위험이 있는 구조물에 구조적인 보강재료로 사용이 가능한가를 검토하였다. 연구 결과, 개발된 무기계 폴리머 복합체는 인장강도, 휨강도 및 접착강도가 유기계 접착제와 유사하게 나타났고 800~100$0^{\circ}C$ 정도로 1시간 가열한 이후에도 상온 시험체 휨내력과 전단내력의 63%, 33% 정도를 유지하여 화재의 위험이 있는 부위에도 사용이 가능한 것으로 판단되었다.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.627-631
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• 2021

Research on induction heating catalyst system was conducted to solve problems of the existing catalyst system for removing volatile organic compounds. In the present study, three types of Ni-based commercial catalysts were employed, and induction heating reaction characteristics including the catalyst volume, composition, heat treatment atmosphere, and position in the coil were investigated. The composition and volume of the catalyst affected the exothermic and toluene oxidation performance in the induction heating system. In particular, the Fe-added catalyst showed high exothermic performance compared to that of other catalysts consisting of more than 99% Ni, but had low toluene oxidation performance. In addition, the heat treatment in an air atmosphere of the Ni-based catalyst drastically reduced the performance. In the induction heating system, the optimal condition for the catalyst was to be located in the center of the coil. The catalyst showed similar activities among seven repeated experiments under the optimal condition derived from this work.

• Journal of the Korean Recycled Construction Resources Institute
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• v.12 no.1
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• pp.47-52
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• 2024

The demand for FRPs that are corrosion-free and have an excellent tensile strength-to-weight ratio. However, there is a lack of research on the mechanical properties of FRP in the form of rebars, especially the changes in performance due to heating. Therefore, in this paper, 60 tensile and compression specimens of CFRP rebars with a diameter of 12 mm were fabricated and subjected to direct tensile and direct compression tests, and their performance was evaluated according to the heating temperature. It was found that as the heating temperature increases above 300 ℃, the performance decrease becomes larger due to the burning of epoxy. The compressive strength was found to be much lower than the tensile strength, but the modulus of elasticity was found to be the same in tension and compression.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.4
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• pp.68-75
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• 2018

This study presents the performance test results and the analyses of the vitiated air heater with high temperature and high pressure. In the performance test, four test conditions and three rake measurement conditions were implemented. In the results of the performance test, the vitiated air heater met targets of temperature and flow rate, and the performance with maximum temperature of 2000 K and maximum combustion pressure of 40 bar was confirmed. Flow rate of provided methane increased 36% more than what was calculated, and 19.6% difference was displayed between measured temperature and theoretically calculated temperature.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.6
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• pp.188-197
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• 2010

This paper presents research result to study the change of structural capacity of reinforced concrete beams with various shear reinforcement ratios after damage by fire load. In addition, fundamental data are given in order to predict the strength variation of RC member due to fire damage by evaluating the previous calculation method codified in codes. Nine RC beam specimens were made and exposed to the fire controled by the standard fire curve. And the structural capacity was evaluated through a failure test under simple support condition. Previous code formula, ACI code and Eurocode were reviewed and used for the calculation of the strength of specimens damaged by fire. From the test, RC beam specimens exhibited very brittle failure when it exposed to fire controled by standard fire curve during more than one hour. And this failure pattern tended to be more serious when shear reinforcement ratio decreased or fire loading duration increased. From the evaluation of the calculation process in code, the change of strength due to fire can be properly predicted if the damage of materials is well defined.