• Title/Summary/Keyword: large fire

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Fire Detection of a Building Using Wireless Multi-point Temperature Sensors (무선 다점 온도센서에 의한 빌딩의 화재 탐지)

  • Kim, Chi-Yeop;Kwon, Il-Bum
    • Journal of the Korean Society for Nondestructive Testing
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    • v.24 no.5
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    • pp.494-498
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    • 2004
  • Fire accidents often happen in large buildings because large buildings are equipped with heavy electrical wiring and piping. When fire is to be occurred in those buildings, it is very dangerous to People and building structures. Therefore, multi-point wireless temperature sensors for large buildings are necessary in order to detect fire in the early time and thus to minimize the loss. A wireless device was composed of the transmitter and receiver. The specification of this device was as follows: 915MHz of transmitted frequency, 4 channels, 9600bps of the transmitted speed, and 10mW of the transmitted power. We confirmed through experiment that the temperature was well sensed and fire location was determined by the 4 channel sensors of the developed sensor system.

Study of Indirect Attack Method of Aerial Fire Firefighting by Helicopter on Forest Fire (헬기에 의한 산불공중간접진화 방법에 관한 연구)

  • Bae, Taek-Hoon;Choi, Youn-Chul
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.24 no.3
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    • pp.55-61
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    • 2016
  • Among the method of aerial fire firefighting, the indirect attack is efficiency way to protect main facilities and it is the aerial fire line construction. According to this study is suggested the fire line construction strategy of indirect attack by helicopter suitable Korea forest fire on theory consideration of indirect attack and experience in practical scene. This study defined that main key points of the fire line construction are accuracy, large quantity, and quickness. Main protection facilities are devided as caution area, warning area, danger area and concern area. Also, it suggested stage-by-stsge from 1 step to 3 step for the aerial fire firefighting correspondence strategy and the fire line construction model. I regard that this study's indirect attack method of the aerial fire firefighting of the fire line construction may be understand about indirect attack tactics and application of indirect attack which is assistance to raise of capability of the aerial fire firefighting with effectiveness and efficiency.

APPLICATION OF PERFORMANCED BASED DESIGN IN FIRE PROTECTION ENGINEERING

  • Cha, David S.
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.423-438
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    • 1997
  • Today's building and fire prevention codes are mostly prescriptive. Prescriptive codes are based on major fires in earlier years that created a need for specific building provision. These codes provide a minimum level of safety. As the general and engineering uses of computers have increased over the years, so has use of computers in the fire protection engineering. This has allowed fire protection engineers to develop alternative approaches to solve today's fire protection problems or to evaluate the performance of a specific fire safety goal. A performance based approach to building and fire codes involves the following: 1) identifying specific goals, such as, safely getting out of the building in 10 minutes, 2) obtain conceptual approval from authorities, 3) define performance level, 4) develop design solutions and identify tools such as, fire tests, models, or methods, to demonstrate that a design will meet the fire protection objective 5) test solutions, 6) present test method and results to the authorities. Some people in the fire protection community consider this to be nothing more than an intellectual exercise, while the others view it as a way to reduce expenses on large project$^4$ Others in fire protection community view this as a way to refine the design process to design fire protection systems to better protect the fire hazards. This paper will focus on application of these tools, specifically computer fire models, to actual cases such as: design of a smoke control system heat transfer analysis and egress of building occupants during potential fires.

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The Fire induced Thermal Stress Analysis of PC Box Bridge (PC Box교량의 화재에 대한 열응력해석)

  • 최창근;이계희;최인혁;김일곤
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.125-132
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    • 1998
  • In this study the fire, due to overturning of oil tanker on the bridge induced heat transfer analysis and thermal stress analysis are carried out. The results of analysis for fire history of 1 hour present very large thermal gradient near the surface. However, the temperature increase of tendon & rebar that is the main resistant member of bridge is not sufficient to change material properties. The Von-Mises yield criteria is used to calculate the depth of delamination, The depth of delamination is about 4cm at center of fire and this value is close to measured value.

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Analysis of Unwanted Fire Alarm Signal Pattern of Smoke / Temperature Detector in the IoT-Based Fire Detection System (IoT 기반 화재탐지시스템의 연기 및 온도감지기 비화재보 신호 패턴 분석)

  • Park, Seunghwan;Kim, Doo-Hyun;Kim, Sung-Chul
    • Journal of the Korean Society of Safety
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    • v.37 no.2
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    • pp.69-75
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    • 2022
  • Fire-alarm systems are safety equipment that facilitate rapid evacuation and early suppression in case of fire. It is highly desirable that fire-alarm systems have low false-alarm rates and are thus reliable. Until now, researchers have attempted to improve detector performance by applying new technologies such as IoT. To this end, IoT-based fire-detection systems have been developed. However, due to scarcity of large-scale operational data, researchers have barely studied malfunctioning in fire-alarm systems or attempted to reduce false-alarm rates in these systems. In this study, we analyzed false-alarm rates of smoke/temperature detectors and unwanted fire-alarm signal patterns at K institution, where Korea's largest IoT-based fire-detection system operates. After analyzing the fire alarm occurrences at the institution for five years, we inferred that the IoT-based fire-detection system showed lower false-alarm rates compared to the automatic fire-detection equipment. We analyzed the detection pattern by dividing it into two parts: normal operation and unwanted fire alarms. When a specific signal pattern was filtered out, the false-alarm rate was reduced to 66.9% in the smoke detector and to 46.9% in the temperature detector.

Study of High-capacity Foam Discharging Systems for Full Surface Fire of Big Oil Tanks (대형 유류저장탱크 전면화재 대응을 위한 대용량포방사시스템 연구)

  • Im, Joo-Yeol;Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.33 no.6
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    • pp.173-180
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    • 2019
  • Oil tank fires need to be suppressed differently from other oil-related fires, due to the high-temperature flames and hot updraft above the tank, in the former case, that cause the destruction of large amounts of foam. We studied high-capacity foam discharge systems based on the standards of the American Petroleum Institute (API), National Fire Protection Association (NFPA), British Standard European Norm (BS EN), and the laws of Japan. The performance of a high-capacity foam discharge system was measured by conducting real fire experiments with model oil tanks. We concluded that lightweight and easily movable high-capacity foam discharge systems should be urgently introduced in domestic operations. Additionally, the obstacles faced by major tanks, such as long-distance installation of large-diameter fire hoses and narrowing of firefighting spaces, should be resolved depending on the conditions of the site.

Effect of External Thermal Insulation Composite System with a Non-combustible Calcium Silicate Based Mineral on The Mitigation for Reducing Fast Spread of Flame (불연성 무기 단열재를 화재확산 방지구조로 적용한 외단열 마감시스템의 화재성능)

  • Lee, Jong-Chan;Park, Jong-Chul;Song, Hun
    • Journal of the Korea Institute of Building Construction
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    • v.16 no.5
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    • pp.397-403
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    • 2016
  • As a building energy saving standard strengthened, The number of building installed external thermal insulation composite system(ETICS) using EPS insulation increased. But frequent fire accident in the buildings installed EIFS using EPS led to strengthening of building fire safety regulation. This study is for fire property of EPS ETICS reinforced with noncombustible calcium silicate-based mineral insulation as a fire spread prevention structure(FSPS). Fire test for large scale wall by ISO 13785-2 was applied and results showed EPS EIFS with FSPS got 3~8 times superior fire safety than normal EIFS by visual investigation. Temperature and heat flux measurement results, which data of upside of specimen were lower than downside, also supported fire safety of EIFS with FSPS.

A Study on the Escape Measures and Fire Protection System Improvement in Discount Stores (대형할인점의 피난대책 및 소방시설 개선방안에 관한 연구)

  • 홍성우;이영재
    • Fire Science and Engineering
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    • v.16 no.4
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    • pp.20-27
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    • 2002
  • This study in focused on proposing the improvement plans for refuge and fire-fighting facilities in large shopping malls that are radically spreading. The main subjects are as follows. - The refuge measure for large shopping malls - Problems of installing the refuge facilities in stores and the solutions - Problems of installing the incendiary facilities in stores and the solutions - Problems of installing the indoor fire plug in stores and the solutions As result of the study, it has turned out that escape stairs which are set up according to the standard of size in the process of design plan, have to be decided for their amount, position, specification, etc, in consideration of the number of residents. It is also required to tighten a standard of installing a sprinkler instead of lightening the fire-fighting section in stores, considering obstacles due to facilities installed and procurement of the escape path. In addition, it needs to lighten a standard of installing the indoor fire plug, which is voluntarily set up at the store section incase of installing a sprinkler to make a practical fire-fighting facility available.

Fire resistance of high strength fiber reinforced concrete filled box columns

  • Tang, Chao-Wei
    • Steel and Composite Structures
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    • v.23 no.5
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    • pp.611-621
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    • 2017
  • This paper presents an investigation on the fire resistance of high strength fiber reinforced concrete filled box columns (CFBCs) under combined temperature and loading. Two groups of full-size specimens were fabricated. The control group was a steel box filled with high-strength concrete (HSC), while the experimental group consisted of a steel box filled with high strength fiber concrete (HFC) and two steel boxes filled with fiber reinforced concrete. Prior to fire test, a constant compressive load (i.e., load level for fire design) was applied to the column specimens. Thermal load was then applied on the column specimens in form of ISO 834 standard fire curve in a large-scale laboratory furnace until the set experiment termination condition was reached. The test results show that filling fiber concrete can improve the fire resistance of CFBC. Moreover, the configuration of longitudinal reinforcements and transverse stirrups can significantly improve the fire resistance of CFBCs.

A Study on Fire Risk Analysis & Indexing of Buildings (건축물의 화재위험의 분석과 지수화에 관한 연구)

  • Chung, Eui-Soo;Yang, Kwang-Mo;Ha, Jeong-Ho;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.10 no.4
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    • pp.93-104
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    • 2008
  • A successful fire risk assessment is depends on identification of risk, the analytical process of potential risk, on estimation of likelihood and the width and depth of consequence. Take the influence on enterprise into consideration, Fire risk assessment could carry out along the evaluation of the risk importance, the risk level and the risk acceptance. A large part of the limitation of choosing the risk assessment techniques impose restrictions on expense and time. If it is unnecessary high level risk assessment or Probabilistic Risk Assessment of buildings, in compliance with the Relative Ranking Method, Fire risk indexing and assessing is possible. As working-level technique, AHP method is useful with practical technique.