• International journal of steel structures
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• v.18 no.4
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• pp.1177-1190
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• 2018

This study presents an analytical framework for estimating the thermo-mechanical behavior of a composite beam exposed to fire. The framework involves: a fire simulation from which the evolution of temperature on the structure surface is obtained; data transfer by an interface model, whereby the surface temperature is assigned to the finite element model of the structure for thermo-mechanical analysis; and nonlinear thermo-mechanical analysis for predicting the structural response under high temperatures. We use a plastic-damage model for calculating the response of concrete slabs, and propose a method to determine the stiffness degradation parameter of the plastic-damage model by a nonlinear regression of concrete cylinder test data. To validate simulation results, structural fire experiments have been performed on a real-scale steel-concrete composite beam using the fire load prescribed by ASTM E119 standard fire curve. The calculated evolution of deflection at the center of the beam shows good agreement with experimental results. The local test results as well as the effective plastic strain distribution and section rotation of the composite beam at elevated temperatures are also investigated.

• Composites Research
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• v.21 no.4
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• pp.1-6
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• 2008

This paper explains fire safety tests of a hybrid composite train carbody with carbon/epoxy sandwich bodyshell and stainless steel underframe. In this study, a large scale mock-up was used to evaluate the fire safety of the composite train carbody. The test was conducted to the bare composite carbody mock-up without interior facilities and the fully equipped one. Tile fire propagation and temperature distribution of the carbon/epoxy bodyshell and the glass phenol interior panels was evaluated under the real fire accident scenario. The test scenario was based on the DaeGu subway fire accident. From the tests, both the surface temperature of the interiors and the composite bodyshell wore lower than tile ignition temperature. In addition, the fire spread along the surface of the interiors and bodyshell was not occurred.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.110-110
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• 2010

Suspension insulator have made use of porcelain insulator mainly, but polymer insulator is using recently. Polymer suspension insulator have advantage that it is light than porcelain insulator. The ageing performance is excellent and it is possible for mass production. There is high possibility of mountain fire because a lot of potential inflammables such as fallen leaves are stacked on the ground Therefore surface aging of polymer insulator most of the overhead transmission lines in Korea are operated on the mountain need analysis of transmission line into forest fire. surface aging property is analyzed by SEM, EDX, XPS, FTIR, DSC in this paper.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.35-36
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• 2013

2차 화염확산체로서의 역할을 할 수 있는 일반 유기폼 침대 매트리스에 착화된 연소성상을 고찰하며 특히 표면 화염확산(flame spread)에 대해서 장방향 및 단방향에 대한 확산속도를 분석함.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.173-180
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• 2003

This paper deals with the experimental results that apply to a new wire by an artificial flame-maker because it's difficult to directly analyze the characteristic of deterioration by a forest fire. Those results include surface characteristics for a conductor. In addition, there's been an experiment and analysis about the surface characteristics of the wire of ACSR 480$\textrm{mm}^2$ which was removed from Pohang area by a forest fire. Then, the database will be made to predict the state of deteriorated wires by a forest fire using those two data, and data necessary to diagnose the life state of an ACSR wire affected by a forest fire will be given.

• Journal of the Korean Wood Science and Technology
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• v.36 no.2
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• pp.1-8
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• 2008

This study was performed to evaluate the burning characteristics of wood-based materials and the effect of surface treatment of fire retardant using cone calorimeter. Four types of wood-based materials, such as Plywood, Oriented Strand Board (OSB), Particle Board (PB) and Medium Density Fiberboard (MDF), were tested at a constant heat flux of $50kW/m^2$ to investigate the time to ignition, mass loss rate, heat release rate, effective heat of combustion, etc. In addition, each type of wood-based material was tested at the same heat flux after fire retardant treatment on the surface to evaluate the effect of this treatment on the burning characteristics. The surface treatment of fire retardant, by the amount of $110g/m^2$, delayed the time to ignition almost twice. However, it was indicated that heat release rate, mass loss rate, and effective heat of combustion were not significantly affected by fire retardants treatment for all types of wood-based materials.

• Fire Science and Engineering
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• v.23 no.5
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• pp.90-95
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• 2009

The wind is very important factor in forest fire spread. Flame spread has a change through wind pattern change in forest fire. In order to analyze the forest fire flame spread rate, change of flame tilt depending on wind may be considering first. This is be cause the flame spread rate varies by the flame tilt changed due to transfer of heat. Especially, as wind speed grow, flame gets closer to surface, heat transfer ratio increase, virgin fuel bed reaches ignition temperature more rapidly, and flame moves faster. This study deduces, through experiment and physical figure analysis, relations on the change behavior of flame tilt due to wind. The value of flame tilt angle calculated from the equation and the experiment value showed average error angle of $3.3^{\circ}$, which is relatively smaller than results of previous studies that used other coefficient. Froude number coefficient A can be calculated in the method provided in this research for estimation of flame tilt angle of virgin fuel bed with varying thermal properties. The research finding is expected to be applied to future studies on flame spread through numerical analysis of heat transfer.

• Fire Science and Engineering
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• v.34 no.4
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• pp.101-106
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• 2020

This study analyzed flame growth characteristics and carbonization patterns when floor materials were burned vertically using a needle flame produced for this study. It was found that PVC flooring was fire retardant and the area under direct flame contracted inward. Vertical combustion causes solidification in the form of a lump at the bottom and also generates soot in a pattern that progresses upwards. This study found that laminated flooring exhibited no fire retarding characteristics and that the laminated layer of its upper surface was destroyed by fire, causing irregular delamination. The carbonization ranges at the left and right sides were determined to be symmetrical. A vertical combustion test of a sample carpet showed that it exhibited no fire-retarding characteristics. It was observed that if heat accumulated in the carpet, the flame formed an ascending air current, and that when flammable materials were present around the flame, they further accelerated the diffusion of the flame. The carbonization pattern at the carpet surface exposed to direct flame revealed that the carpet surface had melted and had flown downwards and that many tiny holes formed on it.

• Journal of Plant Biology
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• v.11 no.4
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• pp.9-20
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• 1968

In general there are few cases which were caused by lightening and no fire was observed to have been caused but by artificial or accidental fires during preliminary survey. And then the most scales of burning in Korea are like the fig. 2. Temperature 5 cm apart from flame at the burning site were known to range from 165$^{\circ}$to 20$0^{\circ}C$ in surface fire on Myozangdong, pine-quercus dominant community and from 120$^{\circ}$ to 145$^{\circ}C$ in surface fire of Wolwoonni, Mischanthus dominant area and from 120$^{\circ}$ to 14$0^{\circ}C$ in ground fire of Wangzinkun, Mischanthus dominant, respectively. Through the preliminary survey, fire indicater plants in Korea were confirmed as Mischanthus coreensis Hack and Carex alterifolia Franch. The plants of highest frequency appeared in the burnt sites were known to as Potentilla cryptotaeniae Max, Mischanthus coreensis Hack, Carex alterifolia Franch and Artemisia brachyphylla Kitamura. Lespedezas were proved as one of the fire tolerant and Pinus densiflora was found out as the lowest intolerant plant to fire. The acidity of burnt soil was decreased according to the considerable amount of ash left on the ground. The acidity of surface soil was more decreased than the below 10cm of soil. The chemical composition(NO3, P, K, Mg, Total-N and Organic-C) of burnt soil was more increased than those of the unburnt sites. And the population changes of soil microflora seemed to have a certain tendency. The population of soil microflora was increased a little according to climatic conditions. Also there was an initial decrease in the population of microflora followed immediately by a significant increase.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.3
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• pp.1-9
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• 2001

The purpose of this study was to evaluate the burning impacts of the surface and crown fire occured in yongsan-ri meongsok-myun of chinju-city, Gyeongnam. Environmental influences like surface runoff and soil erosion changes were investigated by comparisons analysis between burned and unburned area about some initial effects after fire. The results obtained from this study were as followed; 1. The average amount of surface runoff in burned area was more 1.7 times than in unburned area. But it was gradually tend to decrease in burned area as times passed. 2. Factors significantly correlated to amount of surface runoff in burned area shown in order to unit rainfall, accumulated rainfall and sand content, as 0.9466 of multiple correlation coefficient, where as the factors in unburned area were unit rainfall, soil erosion, bulk density and soil hardness, as 0.9738 of multiple correlation coefficient. 3. The average amount of soil erosion in burned area was more 11.2 times than in unburned area. But it was gradually tend to decrease in burned area as times passed. 4. Factors significantly correlated to amount of soil erosion in burned area were surface runoff and unit rainfall, as 0.6305 of multiple correlation coefficient. The factors in unburned area shown in order to surface runoff, sand content, bulk density and unit rainfall, as 0.7879 of multiple correlation coefficient.