• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.295-298
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• 2012

Repair and strengthening is necessary to extend the service life of existing buildings. Polymer-modified cement mortar (PCM) has been extensively used as a high performance material particularly for finishing and repairing works in concrete building because of itsexcellent adhesion, waterproofing, resistance to chemical attack, and workability. As PCM contains organic polymer, it is necessary to clarify its properties at high temperature under fire, on which sufficient data are not available. This paper evaluated the burn-up characteristics of polymer-modified cement mortar with cone calorimeter test, non-combustibility test and flammability test with experimental parameters such as the types of polymer, unit-polymer content, polymer-cement ratio and thickness of the specimen.

• 한국화재소방학회논문지
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• 제31권2호
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• pp.37-43
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• 2017

이 연구에서는 4종의 삼나무, 스프러스, 나왕, 레드파인 시험편을 콘칼로리미터(Cone calorimeter, ISO 5660-1, 2)와 연기밀도시험기(ASTM E 662)를 이용하여 연소성을 시험하였다. 그 결과, 삼나무가 착화시간이 가장 빨랐고 평균열방출율($HRR_{mean}$)이 $58.52kW/m^2$으로 가장 낮게 나타났다. 그리고 레드파인의 평균열방출율($HRR_{mean}$)이 $71.75kW/m^2$으로 가장 높게 나타났다. CO 발생량에서는 나왕과 삼나무가 가장 많이 발생하였고, 반대로 $CO_2$ 발생량에서는 레드파인과 스프러스가 가장 많이 발생하였다. 동적방법에서의 총연기방출율은 레드파인이 연기가 가장 많이 발생하였고, 스프러스가 가장 적게 발생하였다. 정적방법에서의 연기밀도는 레드파인이 훈소(Non-flaming) 방식과 불꽃(Flaming) 방식에서 가장 높았다. 나왕은 훈소(Non-flaming) 방식에서 2번째로 연기가 많이 발생한 데 반하여 불꽃(Flaming) 방식에서는 가장 적게 발생한 것을 알 수 있었다. 열방출율 측면에서 화재위험성은 4가지 시험편 중 레드파인이 가장 높았다. 연기발생 관점으로 보아도 동적인 방식과 정적인 방식 모두 레드파인이 화재 위험성이 가장 높은 재료였다.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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• pp.450-455
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• 2008

We have carried out the test using the cone calorimeter and the smoke density chamber to evaluate the characteristics of the combustion for the car interior materials passed horizontal burning test. We have analysed many parameters related to fire hazard. These parameters are the ignition time, the heat release rate, the maximum average rate of heat emission, the flashover propensity and specific optical density. There was a significant difference in HRR and optical smoke density. The HRR was $185{\sim}446kW/m^2$ and optical smoke density was $119{\sim}1207$. Only horizontal burning test was performed to evaluate the fire hazard for the car interior materials.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.935-940
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• 2005

We generally get the Heat Release Rate by two other method. One is the calculation method from the Oxygen consumption rate and another is the calibration curve method of Temperature rising rate. In this study we compare the results of both test methods with five same specimens. From the test result we get the difference of reproducibility and checked some reasons of the difference. This paper includes some points to be careful for more creditable results for each test method.

• Advances in nano research
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• 제16권2호
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• pp.127-140
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• 2024

Upon direct/indirect exposure to flame or heat, composite structures may burn or thermally buckle. This issue becomes more important in the natural fiber-based composite structures with higher flammability and lower mechanical properties. The main goal of the present study was to obtain an optimal eco-friendly composite system with low flammability and high thermal buckling resistance. The studied composite consisted of polypropylene (PP) and short abaca fiber (AF) with eggshell powder (ESP) and halloysite clay nanotubes (HNTs) additives. An optimal base composite, consisting of 30 wt.% AF and 70 wt.% PP, abbreviated as OAP, was initially introduced based on burning rate (BR) and the Young's modulus determined by horizontal burning test (HBT) and tensile test, respectively. The effects of adding ESP to the base composite were then investigated with the same experimental tests. The results indicated that though the BR significantly decreased with the increase of ESP content up to 6 wt.%, it had a very destructive influence on the stiffness of the composite. To compensate for the damaging effect of ESP, small amount of HNT was used. The performance of OAP composite with 6 wt.% ESP and 3 wt.% HNT (OAPEH) was explored by conducting HBT, cone calorimeter test (CCT) and tensile test. The experimental results indicated a 9~23 % reduction in almost all flammability parameters such as heat release rate (HRR), total heat released (THR), maximum average rate of heat emission (MARHE), total smoke released (TSR), total smoke production (TSP), and mass loss (ML) during combustion. Furthermore, the combination of 6 wt.% ESP and 3 wt.% HNT reduced the stiffness of OAP to an insignificant amount by maximum 3%. Moreover, the char residue analysis revealed the distinct differences in the formation of char between AF/PP and AF/PP/ESP/HNT composites. Afterward, dilatometry test was carried out to examine the coefficient of thermal expansion (CTE) of OAP and OAPEH samples. The obtained results showed that the CTE of OAPEH composite was about 18% less than that of OAP. Finally, a theoretical model was used based on first-order shear deformation theory (FSDT) to predict the critical bucking temperatures of the OAP and OAPEH composite plates. It was shown that in the absence of mechanical load, the critical buckling temperatures of OAPEH composite plates were higher than those of OAP composites, such that the difference between the buckling temperatures increased with the increase of thickness. On the contrary, the positive effect of CTE reduction on the buckling temperature decreased by raising the axial compressive mechanical load on the composite plates which can be assigned to the reduction of stiffness after the incorporation of ESP. The results of present study generally stated that a suitable combination of AF, PP, ESP, and HNT can result in a relatively optimal and environmentally friendly composite with proper flame and thermal buckling resistance with no significant decline in the stiffness.

• 한국가구학회지
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• 제19권6호
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• pp.475-486
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• 2008

In this study, fire-retardant chemicals were melt with mixed composition ratios of dibasic ammonium phosphate and each half of boric acid and borax in hot water, in which hammer-milled chips were immersed to increase swelling of waste particleboards. Also, fire-retardant treated particles from sawn lumber chip and recycled particleboard chip were composed in ratio of 70:30 in core layer to improve boards' properties. Retention ratio of fire-retardant chemicals for the particles for face layer was high due to high specific surface area, and that of sawn lumber chips was somewhat higher than that of recycled particleboard chips. The mixture of particles from sawn lumber chips and recycled PB of 70:30 in weight ratio exceeded bending strength of 100 $kgf/cm^2$. It seemed that the relatively greater portions of dibasic ammonium phosphate affected adversely to dimensional stability, however fire-retardants treatment resulted in distinct effect lowering formaldehyde emission such as $E_0$ type(0.5mg/$\ell$ or less) in KS F 3104. In fire-retardancy, the recycled boards with a mixed ratio of dibasic ammonium phosphate to boric acid borax(50:50 mixture) of 70% to 30% in weight satisfied fire-retardancy 3rd grade in KS F 2271, and also this composition from cone calorimeter test met same standard grade figuring total heat release of 4.6MJ/$m^2$.

• 한국화재소방학회논문지
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• 제22권1호
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• pp.84-92
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• 2008

본 연구에서는 영동지역의 대표 수종인 소나무와 떡갈나무를 대상으로 주요 부위별 열적특성을 고찰하고자 콘칼로리미터 시험을 수행하여 중량변화, 착화시간, 화염유지시간, 발열량 그리고 CO와 $CO_2$ 배출농도를 비교 분석하였다. 소나무와 떡갈나무 모두 가지의 총중량감소가 가장 크게 나타났으며, 낙엽의 착화시간이 9 s 정도로서 가장 빠르게 나타났다. 낙엽과 수피부위의 화염유지시간은 $640{\sim}1,016s$ 정도였으며, 총방출열량은 낙엽비 생엽의 2배 정도인 60.1 $MJ/m^2$로 가장 높게 나타났다. 또한, CO 및 $CO_2$의 최대 배출농도는 떡갈나무의 가지부위가 소나무의 가지보다 2.82배 이상 높게 나타남으로써 소나무와 떡갈나무의 열적특성은 부위별로 많은 차이가 있음을 확인하였다.

• 한국응용과학기술학회지
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• 제27권4호
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• pp.399-406
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• 2010

This study was performed to test the flame retardancy of zelkova sarrata-based materials by the treatment of ammonium salts. Zelkova sarrata plate was soaked by the treatment with three 20 wt% ammonium salt solutions consisting ammonium chloride (AMSL), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP), respectively, at the room temperature. After the drying specimen treated with chemicals, combustion properties were examined by the cone calorimeter (ISO 5660-1). When the ammonium salts were used as the retardant for zelkova sarrata, the flame retardancy improved due to the treated ammonium salts in the virgin zelkova sarrata. However the specimen shows increasing CO over virgin zelkova sarrata and It is supposed that toxicities depend on extents. Also, the specimen with ammonium salts showed the higher total smoke release (TSR) than that of virgin plate. Of specimens treated with ammonium salts the ammonium chloride handled the test side was considered a improved inhibitory effect of combustion.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 추계 학술논문 발표대회
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• pp.63-66
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• 2008

Not only mechanical properties, bonding properties, electro chemical properties, etc. but also fire safety is required in patch repair materials such as polymer modified cement mortar (PCM) which are used to deteriorated reinforced concrete structure. Unfortunately, it is very difficult to choice the appropriate repair materials because there are not enough information about fire safety properties of PCM. In this study, The combustion characters of PCM were evaluated through the heat release rate test and non-combustibility test. The pyrogenicity test uses the cone calorimeter based on the oxygen consumption method. The non-combustibility test is from the temperature change inside the furnace during the test. The effect of the types of polymer and polymer content were evaluated from the series of test. The results are like followings. 1) The higher the W/C of PCM, the lower the gross calorific value and heat generation rate in the heat release rate test. The amount of heat generation of PCM is like the order of VVA, EVA, and SBR in this study. 2) Some materials such as E45-100, E50-100, E60-100, S50-50, and S50-100 were estimated as not appropriate building materials in the non combustibility test.

• 한국화재소방학회논문지
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• 제27권6호
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• pp.15-20
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• 2013

반발 입자 군집 최적화 알고리즘을 이용하여 시편 표면에서의 대류열전달 계수, 방사율 및 화염에 의한 열유속을 예측하였다. 콘 칼로리미터를 이용하여 여러 열유속 조건 하에서의 방무목 시편의 표면 온도와 질량감소율 및 발화시간을 측정하였다. 본 연구에서 최적화된 대류열전달계수, 방사율 및 화염에 의한 열유속을 이용하여 계산된 표면온도는 실험결과와 각 열유속에 대하여 평균오차가 2% 내로 잘 일치하였다. 본 연구에서 제시한 방법을 이용하여 실험적 방법으로 직접 측정하기 매우 어려운 화염이 발생하는 표면에서 열전달과 관련된 여러 물리량을 구할 수 있다.