• Title/Summary/Keyword: large fire

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Design of Large Cone Calorimeter for the Fire Study (화재연구를 위한 대형 콘 칼로리미터의 설계)

  • Lee, Eui-Ju
    • Fire Science and Engineering
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    • v.20 no.4 s.64
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    • pp.65-71
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    • 2006
  • Some major properties such as a heat release rate have been measured experimentally for the validation of fire model and the clarification of fire phenomena as the study is more rigorous recently. Although the reduced-scale experiment also provides the basic data and the physical understanding in fire study, it is not enough to explain real fire problem directly because there is no exact analogy theory between a real fire and the reduced scale model. Therefore, large cone calorimeter have been built and used in a few foreign countries for the measurement of large scale fire. This paper addressed the theoretical background and the description of key features in the design of the facility. It will be a useful guide for implementation of the large scale cone calorimeter in the future.

Development of Large Fire Judgement Model Using Logistic Regression Equation (로지스틱 회귀식을 이용한 대형산불판정 모형 개발)

  • Lee, Byungdoo;Kim, Kyongha
    • Journal of Korean Society of Forest Science
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    • v.102 no.3
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    • pp.415-419
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    • 2013
  • To mitigate forest fire damage, it is needed to concentrate suppression resources on the fire having a high probability to become large in the initial stage. The objective of this study is to develop the large fire judgement model which can estimate large fire possibility index between the fire size and the related factors such as weather, terrain, and fuel. The results of logistic regression equation indicated that temperature, wind speed, continuous drought days, slope variance, forest area were related to the large fire possibility positively but elevation has negative relationship. This model may help decision-making about size of suppression resources, local residents evacuation and suppression priority.

A Study on the Application of Fire Protection Facilities in Large Enclosure Gymnasium (대규모 실내경기장의 소방방재설비 적용현황 분석)

  • Choi, Dong-Ho;Kim, Choon-Dong;Yang, Jeong-Hoon;Cho, Young-Hum
    • Journal of Korean Association for Spatial Structures
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    • v.10 no.2
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    • pp.135-145
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    • 2010
  • The objective of this study is to draw basic data for the application of the fire protection planning for the future plan large enclosure buildings in Korea through an analysis of its characteristics by case studies of the domestic and foreign large scale gymnasiums. In this study, domestic building codes for the fire protection are investigated and fire detection systems, fire extinguishing systems, smoke control systems and evacuation systems of three large scale gymnasiums located at Korea and eight foreign countries are compared and analyzed. The results of this study show that infrared light fire detection system and flame detector for spacial characteristics are potentially used in fire protection systems of large scale gymnasiums: dry type sprinkler and sprinkler water gun are adopted in fire detection system; and smoke accumulation system is widely utilized in smoke control system.

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A simplified analysis of catenary action in steel beams in fire and implications on fire resistant design

  • Wang, Y.C.;Yin, Y.Z.
    • Steel and Composite Structures
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    • v.6 no.5
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    • pp.367-386
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    • 2006
  • This paper describes the results of a numerical investigation of the large deflection behaviour of steel beams under fire conditions, taking into consideration the effect of catenary action provided by the surrounding structures. The main focus is on the development, validation and application of a simplified calculation method that may be adopted in design calculations. Because no experimental result is available for validation of the simplified calculation method, the finite element program ABAQUS has been used to simulate the large deflection behaviour of a number of steel beams so as to provide alternative results for validation of the proposed method. Utilising catenary action has the potential of eliminating fire protection to all steel beams without causing structural failure in fire. However, practical application of catenary action will be restricted by concerns over large beam deflection causing integrity failure of the fire resistant compartment and additional cost of strengthening the connections and the surrounding structures to resist the catenary forces in the steel beams. This paper will provide a discussion on practical implications of utilising catenary action in steel beams as a means of eliminating fire protection. A number of examples will then be provided to illustrate the type of steel framed structure that could benefit the most from exploiting catenary action in fire resistant design.

A Study on the Heat Release Characteristic of Household Items using LSC(Large Scale Cone Calorimeter) (LSC를 이용한 생활용품의 발열량 특성에 관한 연구)

  • Park, Ju Young;Baek, Chang Sun;Lee, Hae Pyeong;Hong, Yi Pyo
    • Journal of the Korean Society of Safety
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    • v.30 no.3
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    • pp.38-44
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    • 2015
  • For this study, fire tests were performed targeting household items (Sofa, Drawer, Refrigerator, Washing machine) using a large cone calorimeter (Large Scale Cone Calorimeter, LSC). The data were obtained focusing on the fire characteristic of the data when the actual fire occurs. The study results showed the following mean HRR of the household items; drawer 2843 KW, sofa 2939 KW, washing machine 719 KW, refrigerator 2907 KW, and THR is found in sofa 2202 MJ, drawer 1559 MJ, refrigerator 1193 MJ, washing machine 627 MJ. From the result, it could be found that the sofa can cause significant heat generation when the fire occurs, and the flashover tendency was found relatively high in compartment fire. In addition, a weight of the four our household items was reduced sharply in a similar time (20min before and after) degree after ignition. The drawer and sofa which has a high heat release can be considered to speed up the fire spread as their weight decrease rapidly and showed relatively weak to the fire compared to the refrigerator and washing machine.

A Study on the Establishment of an Integrated Management System for Forest Fire Prevention and Suppression Measures (산불예방 및 진압대책의 통합관리체계 구축 방안 연구)

  • Lee, Jeong-Il
    • Journal of the Korea Safety Management & Science
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    • v.24 no.2
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    • pp.163-169
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    • 2022
  • Recently, in Korea, if a very large forest fire occurs due to the people's carelessness, it is of great interest because it spreads into a large forest fire. If a wildfire spreads and becomes large, it will inflict great damage (appointment and property), and the damage is irreversible. The best way to extinguish a wildfire is to prevent it before it occurs. If a forest fire occurs due to a failure in prevention, the early firefighting activities to prevent the progress of the forest fire by promptly dispatching it by reporting it and approaching the site as soon as possible should now be managed with a systematic integrated management system. To do so, it is necessary to prepare a preventive system, such as issuing warnings for each weather condition by the Korea Forest Service, consisting of cooperation (support) activities for forest fire prevention by related organizations, etc. In order to minimize the loss of precious lives and forests, measures have been taken to establish a system, to establish a prompt and accurate situation reporting system, and to establish an integrated command system (ICS) for on-site commanders.

A Study on Meteorological Elements Effecting on Large-scale Forest Fire during Spring Time in Gangwon Young-dong Region (강원 영동지역 봄철 산불대형화 영향 기상요소 분석)

  • Lee, Si-Young;Kim, Ji-Eun
    • Journal of the Korean Society of Hazard Mitigation
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    • v.11 no.1
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    • pp.37-43
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    • 2011
  • In this study, we analyzed the meteorological elements, when large forest fires were occurred, The rate of precipitation was 13% of annual average precipitation. Especially, the stronger wind speed, lower humidity and rainfall than average annual record were the distinct feathers on the year when large forest fire occurred in east coast area in Kangwon region. The average, maximum and maximum instantaneous wind speed was 5.9 m/s, 11.3 m/s and 20.9 m/s when large forest fires occurred. The average, maximum and maximum instantaneous wind speed on large fire occurred were 1.8 m/s, 3.0 m/s and 6.9 m/s faster than and average wind speed when whole forest fires occurred. The results indicated that the large forest fire occurrence had a close correlation with meteorological elements.

Numerical analysis to determine fire suppression time for multiple water mist nozzles in a large fire test compartment

  • Ha, Gaghyeon;Shin, Weon Gyu;Lee, Jaiho
    • Nuclear Engineering and Technology
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    • v.53 no.4
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    • pp.1157-1166
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    • 2021
  • In this study, a numerical sensitivity analysis was performed to determine the fire suppression time for a large number of water mist nozzles in a large fire compartment. Fire simulations were performed using FDS (Fire dynamics simulator) 6.5.2 under the same condition as the test scenario 5 of the International Maritime Organization (IMO) 1165 test protocol. The sensitivities of input parameters including cell size, extinguishing coefficient (EC), droplets per second (DPS), and peak heat release rate (HRR) of fuel were investigated in terms of the normalized HRR and temperature distribution in the compartment. A new method of determining the fire suppression time using FDS simulation was developed, based on the concept of the cut-off time by cut-off value (COV) of the heat release rate per unit volume (HRRPUV) and the cooling time by the HRR cooling time criteria value (CTCV). In addition, a method was developed to determine the average EC value for the simulation input, using the cooling time and cut-off time.

An Experimental Study on the Warehouse Mock-up Fire Test (창고 모델 실물화재 특성에 대한 실험적 연구)

  • Kweon, Oh-Sang;Yoo, Yong-Ho;Kim, Heung-Youl
    • Fire Science and Engineering
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    • v.24 no.4
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    • pp.47-54
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    • 2010
  • This study is analyze the damage of warehouse fire accident be made through the fire characteristic database of combustibles and real scale fire test of warehouse mock-up. Combustibles fire tests are carried out for database using RCT (Room Corner Tester) to predict fire growth the goods. A mockup ($3m{\times}3m{\times}2.4m$) of clothes warehouse was built and real scale fire test by LSC (Large Scale Calorimeter) base on the fire characteristic DB. The mock-up of clothes warehouse is made of two type sandwich panels (Glass wool, EPS foam sandwich panel). As a mock-up test result, test 1 (Glass wool sandwich panel) and test 2 (EPS foam sandwich panel) indicating fire growth such as 5 MW, 11 MW of maximum HRR (Heat Release Rate).

An Quantitative Analysis of Severity Classification and Burn Severity At the targe-fire Areas Using NBR Index of Landsat Imagery (Landsat NBR지수를 이용한 대형산불 피해지 구분 및 피해강도의 정량적 분석)

  • Won, Myoung-Soo;Koo, Kyo-Sang;Lee, Myung-Bo
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.231-237
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    • 2007
  • To monitor process of vegetation rehabilitation at the damaged area after large-fire is required a lot of manpowers and budgets. However the analysis of vegetation recovery using satellite imagery can be obtaining rapid and objective result remotely in the large damaged area. Space and airbone sensors have been used to map area burned, assess characteristics of active fires, and characterize post-fire ecological effects. Burn severity incorporates both short- and long-term post-fire effects on the local and regional environment. Burn severity is defined by the degree to which an ecosystem has changed owing to the fire. To classify fire damaged area and analyze burn severity of Samcheok fire area occurred in 2000, Cheongyang fire 2002, and Yangyang fire 2005 was utilized Landsat TM and ETM+ imagery. Therefore the objective of the present paper is to quantitatively classify fire damaged area and analyze burn severity using normalized burn index(NBR) of pre- and post-fire's Landsat satellite imagery.

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