• 한국안전학회지
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• 제8권4호
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• pp.107-113
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• 1993

Small rectangular explosion chamber of its size 25cmX25cmX32cm with a circular bursting diaphram at the top was used to study the mechanism of gas explosion to fire transition phenomena, the process of ignition of solid combustibles during a gas explosion. To visulize the explosion to fire transition phenomena, transparent acryl window and high speed camera system were used. The test piece of solid combustible in this experiments was a 5cm$\times$5cm square sheet of newspaper which was placed in the explosion chamber filled with a LPG-air mixture. The mixture was ignited by an electric spark at the center of the chamber. Explosion to fire transition phenomena and the behavior of out flow and in flow of gas through the opening yielded by bursting the diaphram was visualized with shlieren system and without shlieren system. Diameter of a bursting dlaphram at the top of the explosion chamber was varied 5cm, 10cm, and 15cm, and the position of test piece were varied with 6 point. Explosion pressure was measured with strain type pressure transducer, and the weight difference of the test piece before and after each experimental run was measured. By comparing the weight difference of solid combustibles before and after the experiment and the behavior of out flow and inflow of gas after explosion, it was found that the possibility of ignition was depends on the LPG-air mixture concentration and the exposure period of test piece to the burnt gas. Test result of this experiments it was found that the main factor of this phenomena are that heat transfer to the test piece, and the pyrolysis reaction of test piece. Based on the results, the mechanism of the explosion to fire transition phenomena were inferred ; gas explosion- heat transfer to solid combustibiles ; pyrolysis reaction of solid combutibles : air inflow ; mixing of the pyroly gas with air ignition.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.371-372
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• 2009

본 연구는 정량 모르타르 개발 및 활용을 위한 기초적 연구로서, 경량 잔골재를 사용한 경량 모르타르에 석고를 혼입하여 내화 피복용 바름재로서 사용가능한 최적의 배합을 도출하고자 하였다.

• 한국농림기상학회지
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• 제20권4호
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• pp.357-365
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• 2018

본 연구는 울산광역시 봉대산 산불 훼손 복원지를 대상으로 토양개량제 처리가 토양층에 매설된 wood stakes의 분해율과 유기 탄소 및 질소 동태에 미치는 영향을 조사하기 위하여 실시하였다. 산불 훼손 복원지에 식재된 튤립나무, 상수리나무, 왕벚나무, 곰솔 조림지와 미복원지를 대상으로 2015년 3월 토양 0~15cm 깊이에 wood stakes를 매설한 후, 2년 동안 각 1회씩 토양개량제(CLB: 복합비료 + 석회 + 목탄 처리구; LB: 석회 + 목탄 처리구)를 처리하고, 2015년 10월, 2016년 3월, 2016년 10월 채취하여 분해율과 유기탄소 및 질소 농도를 조사하였다. Wood stakes 분해율의 경우 토양개량제 처리구와 대조구 사이에 유의적인 차이는 없었으나, 유기 탄소 잔존율의 경우 대조구(43.7%), CLB처리구(71.3%), LB처리구(71.6%) 순으로 토양개량제 처리구의 탄소 무기화가 대조구에 비해 낮게 나타났다. Wood stakes 내 질소 잔존율의 경우도 대조구가 29.7%로 LB처리구 52.6%에 비해 낮아 탄소 무기화율과 유사한 경향을 보였다. 본 연구결과에 따르면 산불 훼손 복원지에 토양개량제 처리는 wood stakes의 탄소 및 질소 무기화를 지연하는 것으로 나타났다.

• Advances in materials Research
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• 제5권1호
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• pp.21-34
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• 2016

Fire is one of the most destructive powers to which a building structure can be subjected, often exposing concrete elements to elevated temperatures. The relative properties of concrete after such an exposure are of significant importance in terms of the serviceability of buildings. Unraveling the heating history of concrete and different cooling regimes is important for forensic research or to determine whether a fire-exposed concrete structure and its components are still structurally sound or not. Assessment of fire-damaged concrete structures usually starts with visual observation of colour change, cracking and spalling. Thus, it is important to know the effect of elevated temperatures on strength retention properties of concrete. This study reports the effect of elevated temperature on the mechanical properties of the concrete specimen with polypropylene fibres and cooled differently under various regimes. In the heating cycle, the specimen were subjected to elevated temperatures ranging from $200^{\circ}C$ to $800^{\circ}C$, in steps of $200^{\circ}C$ with a retention period of 1 hour. Then they were cooled to room temperature differently. The cooling regimes studied include, furnace cooling, air cooling and sudden cooling. After exposure to elevated temperatures and cooled differently, the weight loss, residual compressive and split tensile strengths retention characteristics were studied. Test results indicated that weight and both compressive and tensile strengths significantly reduce, with an increase in temperature and are strongly dependent on cooling regimes adopted.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년도 추계학술발표대회 논문집
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• pp.213-216
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• 2009

The purpose of this study is analyzing temporal flow about 20 detailed performance items in the "Housing Performance Grading Indication System". This study try to figure out situations according grade in detailed performance item and to analyze change item about 112 cases(2 cases in 2006, 15 cases in 2007, 46 cases in 2008, 49 cases in 2009), from January 9, 2006 which system is undertaken, to October, 2009. This system consists of 5 main performance section, 14 performance categories and 20 detailed performance items. 5 main performance parts are Noise and Acoustics(Light-weight impact sound control, heavy-weight impact sound control, sound control of toilet, sound control of party wall), Long-life(flexibility, remodeling & maintenance, durability), Landscape & Indoor Environment(landscape, formaldehyde control & ventilation, daylighting, thermal environment), Welfare & Barrier-free(playground and community center, welfare space, barrier-free design), Fire Safety(fire safety, safe place, fire-resisting quality). Total efficiency about housing can understand systematically of 20 perfomance items though this research.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.436-437
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• 2006

Porcelain insulators have generally been used in Korea but polymer insulators which are superior in that they are light weight, explosion proof, impact proof, economical with construction characteristics, have been in use for the 154kV transmission line since 1999 following a worldwide trend towards the reduced weight, simplification and compact usage of new material insulators. However there have been approximately 500 cases of forest fires in Korea, so the transmission lines that for the most part pass through mountainous areas have been highly effected and the highly polymerized compound polymer insulator has raised concern about reliability in cases of exposure to forest fires. Therefore for the reliability assessment of the effect of forest fires on polymer insulators, mechanical and electrical characteristics are analyzed by an artificial flare test device and transmission facility surrounding conditions along with forest fire characteristics are surveyed. In addition to this, actual 90kV energized transmission line was tested with an artificial forest fire and the expanded usage of polymer insulators is presented through the analysis of mechanical and electrical characteristics and physical properties, and a study on the influence of forest fires on polymer insulators.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년 추계학술발표대회 논문집
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• pp.479-482
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• 2008

The purpose of this study is a proposal about the flexibility of the performance category to revitalize the "Housing Performance Grading Indication System". This system consists of 5 main performance parts, 14 performance categories and 20 detailed performance lists. 5 main performance parts are Noise and Acoustics(Light-weight impact sound control, heavy-weight impact sound control, sound control of toilet, sound control of party wall), Long-life(flexibility, remodeling & maintenance, durability), Landscape & Indoor Environment(landscape, formaldehyde control& ventilation, daylighting, thermal environment), Welfare & Barrier-free(playground and community center, welfare space, barrier-free design), Fire Safety(fire safety, safe place, fire-resisting quality). The flexibility of the performance category is conformed to Long-life housing related grading and can realize the Long-life housing in response to resident needs about the space rearrangement. Now, The flexibility of the performance category is limited to the evaluation of the private space, that is, the Skeleton evaluation. This study would suggest alternatives to improve uppermost limits through analyzing 60 examples from January 9th 2009 to October 30th 2008. The flexibility of the performance category is possible to estimate not only the Skeleton evaluation but also the Infill evaluation in response to social changes.

• 한국화재소방학회논문지
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• 제21권2호
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• pp.30-35
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• 2007

고분자 물질의 화재 위험성 및 화재시 인명 피해의 감소를 위한 기초자료로 제시하고자 난연제 및 금속분말의 첨가에 의한 난연성 평가를 수행하였다. 본 연구를 위하여 중량감소율,한계산소지수 및 탄화층 생성량 측정, 연기 중량 농도 및 일산화탄소 발생량 측정의 실험을 수행하였다. 금속분말과 난연제를 함유한 acrylonitrile butadiene styrene은 낮은 중량감소율을 나타내었고, 한계산소지수 및 탄화충 생성량은 증가하였으며, 연기 중량 농도 및 일산화탄소의 발생량도 감소하는 결과를 나타내었다. 또한 가장 효과적인 복합체는 tricresyl phosphate-Mo 복합체로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제32권6호
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• pp.7-13
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• 2004

In this study, the Korean pine wood (Pinus densiflora Sieb. et Zucc) and Italian poplar wood (Populus euramericana Guinier) was treated with a mixture of monoammonium phosphate (MAP) and boric acid. Their usability as fire retardant and as decay-resistant construction and interior materials were evaluated by testing of chemicals, corrosion rate and absorption rate, weight loss and chemical contents. An experiment was performed to compare treated pine wood and Italian poplar wood. According to the results, Italian poplar wood had higher specific gravity and retention of chemicals than pine wood, and treated wood showed higher decay-resistance than untreated one. Weight loss was less in treated wood than untreated one because the degree of decay was lower in the former than the latter. Corrosion rate and absorption rate met the KS standard for wood preservative performance. The chemical contents analysis was carried out to determine the degree of decay and it was found that the preservative effect of chemical treatment was lower in Italian poplar wood than in pine wood.

• 한국기계가공학회지
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• 제10권3호
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• pp.28-32
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• 2011

The safety of transporting equipment in a cryogenic condition is one of important problems under the circumstances that the application weight of natural gas is gradually increasing. As a larger disaster may be generated by leakage of oil or gas from valves in case of fire occurrence of a ship, the present research applied a numerical analysis method on thermal stress distribution and deformation, etc. to the design of ball valves satisfying fire safety test's specification(API607) to prevent this. In addition, the present research progressed fire safety tests and compared the test result with numerical analysis results. The Max stress by parts was confirmed through thermal analysis of major parts to evaluate safety. The fire safety test was progressed according to the regulation of API607.