• Fire Science and Engineering
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• v.10 no.2
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• pp.13-19
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• 1996

An estimation methodology, based on statistics and numerical method, has been developed for estimating the upper explosive limits(UEL) of paraffinic and olefinic hydrocarbon compounds. With proposed method, the UEL has been calculated for 24 paraffinic and 10 olefinic hydrocarbon compounds. The estimated the UEL agree with the experimental values within a few percent. A comparisond with four other methods avaiable in the literature are also presented. It is hoped eventually that this method will permit estimation of the UEL with improved accuracy and broader application for other compounds.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.485-488
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• 2008

Fire intensity in tunnel fire is very severe, which might cause the spalling on the surface of shotcrete and concrete lining exposed to the heat as well as rapidly-reducing stress due to heat transfer by steel material such as anchor embedded in tunnel which plays the critical role in securing the stability of the tunnel. In this study, a fire test to identity the heat intensity(Modifired Hydrocarbon Curve) and the fire resistance of steel materials embedded as parameters, was carried out. And the evaluation to identify the thermal damage, which was based on critical temperature range for thermal damage of steel materials determined according to the road tunnel fire resistance standard established by ITA(International Tunneling Association).

• Journal of Ocean Engineering and Technology
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• v.35 no.3
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• pp.203-215
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• 2021

Current industrial practices and approaches are simplified and do not describe the actual behavior of plated elements of offshore topside structures for safety design due to fires. Therefore, it is better to make up for the defective methods with integrated fire safety design methods based on fire resistance characteristics such as residual strength capacity. This study numerically investigates the residual strength of steel stiffened panels exposed to hydrocarbon jet fire. A series of nonlinear finite element analyses (FEAs) were carried out with varying probabilistic selected exposures in terms of the jet fire location, side, area, and duration. These were used to assess the effects of exposed fire on the residual strength of a steel stiffened panel on a ship-shaped offshore structure. A probabilistic approach with a feasible fire location was used to determine credible fire scenarios in association with thermal structural responses. Heat transfer analysis was performed to obtain the steel temperature, and then the residual strength was obtained for the credible fire scenarios under compressive axial loading using nonlinear FEA code. The results were used to derive closed-form expressions to predict the residual strength of steel stiffened panels with various exposure to jet fire characteristics. The results could be used to assess the sustainability of structures at risk of exposure to fire accidents in offshore installations.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.205-205
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• 2012

선박에서는 화재안전목표를 달성하기 위해 선박을 방화구획화 함으로써 발화의 지점에서 화재를 차단하여 인근지역으로 확산 되지 않도록 하고 있다. 또한 방화구획을 관통하는 파이프, 덕트 및 전선관통부 등을 통하여 유독가스 및 화염이 순식간에 이동하게 되며, 한쪽 구역에서 발생한 화재의 영향이 다른 구역으로 영향을 미치게 되므로 화염에 의한 피해를 방지하고 불길을 차단하기 위하여 관통부재에 대하여 해당 방화구획과 동등한 성능을 요구하고 있다, 선박에 적용되고 있는 방화구획의 등급은 용도에 따라 일반 상선 등에는 "C ~ A"급, 해양플랜트에는 "C ~ H"급 등급이 요구되고 있다. 그러나 현재 국내 선박 기자재 제작 기술은 "A"급에 머물러 있고 최근 국내 조선소의 해양플랜트 수주 증가와 해양플랜트로의 사업전환으로 관련기자재기업에서 "H"급 기자재 개발에 많은 관심을 가지고 개발 시도를 하고 있다. 이에 본 논문에서는 "H" 급 방화구획에 적용되고 있는 탄화수소계(Hydrocarbon Fire) 내화시험기준과 "H"급 Fire Damper의 단열두께에 따른 탄화수소계(Hydrocarbon Fire) 내화성능실험을 통한 방화 댐퍼의 비 노출면에 대한 방열성능 확보방안에 대하여 언급하고자 한다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.11a
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• pp.323-327
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• 2007

• Computers and Concrete
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• v.25 no.6
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• pp.497-507
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• 2020

This paper presents a numerical method for evaluating fire performance of prestressed concrete (PC) T shaped bridge girders under combined effect of structural loading and hydrocarbon fire exposure conditions. A numerical model, developed using the computer program ANSYS, is employed to investigate fire response of PC T shaped bridge girders by taking into consideration structural inherent parameters, namely; arrangement of prestressing strands with in the girder section, thickness of concrete cover over prestressing strands, effective degree of prestress and content of prestressing strands. Then, a sequential thermo-mechanical analysis is performed to predict cross sectional temperature followed by mechanical response of T shaped bridge girders. The validity of the numerical model is established by comparing temperatures, deflections and failure time generated from fire tests. Through numerical studies, it is shown that thickness of concrete cover and arrangement of prestressing strands in girder section have significant influence on the fire resistance of PC T shaped bridge girders. Increase in effective degree of prestress in strands with triangular shaped layout and content in prestressing strands can slow down the progression of deflections in PC T shaped bridge girder towards the final stages of fire exposure, to thereby preventing sudden collapse of the girder. Rate of deflection based failure criterion governs failure in PC T shaped bridge girders under most hydrocarbon fire exposure conditions. Structural inherent parameters incorporated into sectional configuration can significantly enhance fire resistance of PC bridge girders; thus mitigating fire induced collapse of these bridge girders.

• Structural Engineering and Mechanics
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• v.62 no.6
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• pp.663-674
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• 2017

This paper presents an approach for evaluating performance of prestressed concrete (PC) bridge girders exposed to fire. A finite element based numerical model for tracing the response of fire exposed T girders is developed in ANSYS. The analysis is carried out in three stages, namely, fire temperature calculation, cross sectional temperature evaluation, and then strength, deformation and effective prestress analysis on girders exposed to elevated temperatures. The applicability of the computer program in tracing the response of PC bridge girders from the initial preloading stage to failure stage, due to combined effects of fire and structure loading, is demonstrated through a case study, and validated by test data of a scaled PC box girder under ISO834 fire condition. Results from the case study show that fire severity has a significant influence on the fire resistance of PC T girders and hydrocarbon fire is most dangerous for the girder. The prestress loss caused by elevated temperature is about 10% under hydrocarbon fire till the girder failure, which can lead to the increase in deflection of the PC girder. The rate of deflection failure criterion is suggested to determine the failure of PC T girder under fire.

• Fire Science and Engineering
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• v.4 no.1
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• pp.59-62
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• 1990

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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• pp.82-89
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• 2014

In this paper, fire resistance test was carried out to obtain class H-120 thermal insulation of fire dampers according to a hydrocarbon fire conditions. Specimens were fabricated three different types according to the change of the insulation system applied to damper blade and coaming which were measured surface temperature by performing the fire resistance test. As a test result, specimen-1, 2 of an uninsulated damper blade were exceeded thermal insulation acceptance criteria at 21 minutes, 46 minutes respectively, but specimen-3 of an insulated damper blade was satisfied thermal insulation acceptance criteria during 120 minutes. The test results showed that the insulation of the damper blade was an important factor in the fireproof performance of fire dampers concerning the coaming length minimum 500 mm on the unexposed side as specified test standard.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.17-20
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• 2008

Numerical simulations were performed for the prediction of the flame structure of a hydrocarbon flame interacting with a hydrogen flame. Methane was used as a hydrocarbon fuel in this study. The interaction of two 1D premixed flames established in counterflow geometry was investigated. The temperature of the flame interacting with each other was much higher and the flame thickness was wider at a global strain of $1000\;s^{-1}$ than normal methane flame.