• Title/Summary/Keyword: fire damage evaluation

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Damage Evaluation of Bi-directionally Prestressed Concrete Panels under Blast-fire Combined Loading (폭발 후 화재하중 시나리오에 따른 2방향 프리스트레스트 콘크리트 패널부재의 손상도 평가)

  • Choi, Ji-Hun;Choi, Seung-Jai;Kim, Tae-Kyun;Kim, Jang-Ho Jay
    • Journal of the Korea Concrete Institute
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    • v.29 no.3
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    • pp.237-248
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    • 2017
  • Frequent terror or military attack by explosion, impact, fire accidents have occurred recently. These attacks and incidents raised public concerns and anxiety of potential terrorist attacks on important infrastructures. However, structural behavioral researches on prestressed concrete (PSC) infrastructures such as Prestressed Concrete Containment Vessel (PCCV) and Liquefied Natural Gas (LNG) storage tanks under extreme loading are significantly lacking at this time. Also, researches on possible secondary fire scenarios after terror and bomb explosion has not been performed yet. Therefore, a study on PSC structural behavior from an blast-induced fire scenario was undertaken. To evaluate the blast-fire combined resistance capacity and its protective performance of bi-directional unbonded PSC member, blast-fire tests were carried out on $1,400mm{\times}1,000mm{\times}300mm$ PSC specimens. Blast loading tests were performed by the detonation of 25 kg ANFO explosive charge at 1.0 m standoff distance. Also, fire and blast-fire combined loading were tested using RABT fire loading curve. The test results are discussed in detail in the paper. The results can be used as basic research references for related research areas, which include protective design simulation under blast-fire combined loading.

A Study on Fire Extinguishing Performance Evaluation of Compressed Air Foam System (압축공기포 소화설비의 소화성능 평가에 관한 연구)

  • Lee, Jang-Won;Lim, Woo-Sub;Kim, Sung-Soo;Rie, Dong-Ho
    • Fire Science and Engineering
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    • v.26 no.5
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    • pp.73-78
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    • 2012
  • This research is to evaluate the fire extinguishing performance of Compressed Air Foam System and this test was conducted using Foam Head System. Compressed Air Foam System adopt the methods of causing the foam by mixing compressed air in foam-aqueous solution, In Overseas, CAFS (Compressed Air Foam System) is generally used because long distance discharge is possible and the water damage can be minimized by reducing the water usage. In this study, Comparative analysis on fire extinguishing effect is done through test to compare the performance between Foam System applied existing air mixture method and Compressed Air Foam System applied AFFF 3 %, foam-extinguishing-agent based on UL162 standard. In Compressed Air Foam System, the volume proportion of air mixture to foam-aqueous solution is 1 to 1 and discharging flow rate is 140 L/min, 160 L/min, 180 L/min, 200 L/min each. As a result of the test, in terms of fire extinguishing performance, fire suppression time for Compressed Air Foam Systems is shorter than for General Air Mixture System in all flow conditions.

Evaluation of the Radiant Heat Effects according to the Change of Wind Velocity in Forest Fire by using WFDS (WFDS를 이용한 풍속에 따른 산림화재 복사열 강도 평가)

  • Song, Dong-Woo;Lee, Su-Kyung
    • Fire Science and Engineering
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    • v.27 no.3
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    • pp.1-7
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    • 2013
  • The wildland fire intensity and scale are getting bigger owing to climate change in the world. In the case of domestic, the forest is distributed over approximately 63.7 % of country and the main facilities like a industrial facility or gas facility abuts onto it. Therefore there is potential that the wildland fire is developed to a large-scale disaster. In this study, the effect distances of the radiant heat flux from the crown fire are analysed according to the change of wind velocity. The safety criteria concerning the radiant heat flux to influence on the surrounding were researched to analyse the effect distances. The criteria of radiant heat flux were chosen $5kW/m^2$, $12.5kW/m^2$, $37.5kW/m^2$. WFDS, which is an extension of NIST's Fire Dynamics Simulator, was used to consequence analysis of the forest fire. In order to apply the analysis conditions, it is researched the forest conditions that is generally distributed in domestic region. As the result, the maximum effect distances by radiant heat were showed at the horizontal and vertical direction. When the wind velocity varied from 0 to 10 m/s, the maximum effect distance increased as the wind velocity increases. Interesting point is that the maximum effect distance were shown at the wind velocity of 8 m/s. The maximum effect distance was decreased according as the fuel moisture of trees increase. This study can contribute to analyse quantitative risk about the damage effect of the surrounding facilities caused by wildland fire.

Damage of Steel Composite Hollow RC SFT under Fires (강합성 중공 RC 해중터널의 화재시 손상도 분석)

  • Seo, JiHye;Han, Taek Hee;Han, Sang Hun;Park, Woo-Sun;Won, Deok Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.7
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    • pp.4626-4633
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    • 2014
  • The research is being conducted on a SFT (Submerged Floating Tunnel), because of increased exchange among nations and abnormal weather-disasters and new transportation infrastructure has attracted interest. However, studies in this are almost in the early stages around the world and various researches will be needed to promote the safety form the disaster. In this paper, heat transfer analysis was applied among the structural performance evaluation of a SFT if afire occurs in the tunnel. The analysis model of the SFT was performed as steel composite RC hollow. The impact of heat by fire under a range of fire scenarios was analyzed and prevention techniques were examined.

A Comparative Study on Toxic Gas Index and Stop Time of Mouse Activity (연소독성지수와 마우스 행동정시시간 비교 연구)

  • Cho, Nam-Wook;Lee, Jong-Cheon;Rie, Dong-Ho
    • Fire Science and Engineering
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    • v.25 no.4
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    • pp.35-41
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    • 2011
  • Casualties due to toxic smoke products have been reported as major fire damage. There are various tests in order to evaluate toxic smoke from a fire at home and abroad, and KS F 2271 as a test of the gas hazard of building finish materials has been conducted in Korea. The current test of the gas hazard exposes rodent, laboratory rat, to smoke gases to evaluate combustion gas toxicity by measuring acting time of that. this study performed a test of the gas hazard for combustible polymer material, Urethane and rubber flooring, and determined gases with the FT-IR. Quantitative results compared with standard value defined in BS6853 and toxicity index (R) was calculated. Using relative comparison with animal test and the toxicity index, We tried a variety of toxicity evaluation by correlation analysis of two tests.

Evaluation Techniques for Residual Structural Performance of a Reinforced Concrete slab under Fire Damage (화재 피해를 입은 철근콘크리트 슬래브의 잔존 구조성능 평가기법)

  • Choi, Kwang-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.588-594
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    • 2020
  • This study proposes non-destructive rebound-hardness and ultrasonic testing methods to more accurately evaluate the residual structural performance of reinforced concrete structures in a fire. Techniques are also proposed to assess the stiffness used in the deflection calculation with natural frequencies obtained by vibration tests. In the compressive strength evaluation using rebound hardness, the residual compressive strength of thick specimens and a larger water/cement (W/C) ratio were shown to be large. The homogeneity of concrete at high temperature compared to ambient temperature conditions was assessed by the velocity of ultrasonic waves that penetrate the concrete, and it followed W/C or thickness of slab makes little different results. To assess the stiffness of fire-damaged slabs and increase in deflection, the natural frequency was measured by vibration tests and incorporated into the equation of the stiffness. The application of this technique to the slab experiment showed that it can be a very reasonable evaluation technique. In addition, to evaluate the residual strength of a member after fire, a test of the strength of a component was carried out during and after heating.

A Study on the Effective Method to Producing Data for The ROKA Live Fire Training Range Safety (한국군 실 사격 훈련간 효율적인 안전지대 데이터 구축 방안 연구)

  • Lee, June-Sik;Choi, Bong-Wan;Oh, Hyun-Seung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.38 no.3
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    • pp.64-77
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    • 2015
  • An effective method for produce munitions effectiveness data is to calculate weapon effectiveness indices in the US military's Joint Munitions Effectiveness Manuals (JMEM) and take advantage of the damage evaluation model (GFSM) and weapon Effectiveness Evaluation Model (Matrix Evaluator). However, a study about the Range Safety that can be applied in the live firing exercises is very insufficient in the case of ROK military. The Range Safety program is an element of the US Army Safety Program, and is the program responsible for developing policies and guidance to ensure the safe operation of live-fire ranges. The methodology of Weapon Danger Zone (WDZ) program is based on a combination of weapon modeling/simulation data and actual impact data. Also, each WDZ incorporates a probability distribution function which provides the information necessary to perform a quantitative risk assessment to evaluate the relative risk of an identified profile. A study of method to establish for K-Range Safety data is to develop manuals (pamphlet) will be a standard to ensure the effective and safe fire training at the ROK military education and training and environmental conditions. For example, WDZs are generated with the WDZ tool as part of the RMTK (Range Managers Tool Kit) package. The WDZ tool is a Geographic Information System-based application that is available to operational planners and range safety manager of Army and Marine Corps in both desktop and web-based versions. K-Range Safety Program based on US data is reflected in the Korean terrain by operating environments and training doctrine etc, and the range safety data are made. Thus, verification process on modified variables data is required. K-Range Safety rather than being produced by a single program, is an package safety activities and measures through weapon danger zone tool, SRP (The Sustainable Range Program), manuals, doctrine, terrain, climate, military defence M&S, weapon system development/operational test evaluation and analysis to continuously improving range safety zone. Distribution of this K-range safety pamphlet is available to Army users in electronic media only and is intended for the standing army and army reserve. Also publication and distribution to authorized users for marine corps commands are indicated in the table of allowances for publications. Therefore, this study proposes an efficient K-Range Safety Manual producing to calculate the danger zones that can be applied to the ROK military's live fire training by introducing of US Army weapons danger zone program and Range Safety Manual

Serviceability Evaluation of Slim Composite Floor System (슬림 합성보 바닥시스템의 사용성 평가)

  • Eun, Hee-Chang
    • KIEAE Journal
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    • v.8 no.6
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    • pp.63-70
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    • 2008
  • Slim floor construction is becoming used throughout many countries. It combines the advantages of flat slab construction with significant inherent resistance to fire. The slim floor system with web openings leads to the reduction of its self-weight. Although the system has enough strength and stiffness, it is necessary to evaluate and improve the effects of dynamic vibration to be able to annoy the residents. Thus, this study evaluates the serviceability of vibration effects based on the dynamic test of five slim composite beams. Based on the experimental results, the initial stiffness and natural frequency of all specimens exhibit the similar trend regardless of the opening and the shape of cross section. The decrease in natural frequency is deeply related to the reduction in the stiffness of specimens and thus, it can be concluded that the damage of slim composite floor can be detected by the measurement of natural frequency instead of the load-carrying capacity and the stiffness.

Advances in ship survivability against underwater explosions

  • Shin, Young S.
    • Ocean Systems Engineering
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    • v.1 no.2
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    • pp.111-119
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    • 2011
  • Mines, torpedoes and improvised explosive devices (IED) pose a serious threat to the survivability of naval combatants. Inasmuch, a major goal in the design of modern combatant ships has been to eliminate or at least reduce the devastating damage caused by underwater explosion events. Even though there has been extensive research performed on the various underwater explosion phenomena and their associated effects, effective shock testing and shock proofing strategies for naval ship systems have proven to be illusive. Through the use of modeling and simulation (M&S), live fire test and evaluation (LFT&E) and laboratory testing, general guidelines for the shock hardening of shipboard equipment and systems have been developed. In this paper, current aspect of ship survivability has been addressed and future direction is discussed.

Development of Burn Ointment using Algin (Algin을 이용한 화상연고제의 개발)

  • Jung, Duck-Chae;Lee, Ki-Chang
    • Journal of the Korean Applied Science and Technology
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    • v.16 no.3
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    • pp.187-191
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    • 1999
  • Burns can be caused by fire, chemicals, heated object and fluids. Distinguishing a minor burn from a more serious burn involves determining the degree of damage to the tissues of the body. Algin is known as natural polymer marine plants, we prepared the official burn ointment which is made by Algin. This burn ointment was covered on the skin wound of artificial burned and their effect of healing was investigated by the evaluation of histological and hematological change as a function of time. The result of rats test showed that burn ointments made from Algin was effective in formation of the new tissue and reduction of inflammation.