• 대한원격탐사학회지
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• 제17권4호
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• pp.359-368
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• 2001

The prototype of forest fire management system on Web was studied. In the architecture of this system, one of the most important concerns is to handle load upcoming to Web Server so that it provides Web service without any delay or failure. In order to solve this problem, the agent is designed on dispatcher in a Web server cluster and implemented to distribute load dynamically by considering the information related to load coming to the Web Server such as the number of connection to the Map Server. The proposed forest fire management system has user-friendly interface with the GIS mapping functionality by selecting Map Objects Internet Map Server (MO IMS) as Map Server and is implemented using Java as programming language.

• 한국해양공학회지
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• 제35권1호
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• pp.59-74
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• 2021

To validate the fire safety assessment of structures, many structural experiments under fire load have been conducted. However, most of these experiments were conducted in restricted environments, such as inside a furnace, and experiments were seldom carried out in open space. In this study, an experimental study on H-beams, frequently used as structural reinforcements, was carried out for validating the thermal-structural analysis method under development. A 1.8 MW burner fire was adopted with each end of the H-beam fixed without a mechanical load. Gas temperature, steel surface temperature, and displacements were then measured. During the experiment, gas and steel temperatures were obtained at 9 and 17 points near the H-beam, respectively. In addition, the vertical and horizontal displacements of the H-beam under fire load at 6 points were obtained. Furthermore, it was verified that the stable displacement measurements via the contact and non-contact methods were feasible in harsh environments where flames and smoke were both present.

• 한국안전학회지
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• 제27권3호
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• pp.49-56
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• 2012

The purpose of this paper is to present a model for operating an emergency power system(EPS) that can secure a sufficient power supply used in case of a fire by analyzing the status of power supplies for emergency and firefighting operations. Investigations on the one of the causes of the operational failure of firefighting systems show evidence of EPS. Generally, when power to a building is interrupted, EPS supplies the emergency load(excepted firefighting load) first. When a power outage and a fire occur simultaneously, the EPS must be able to supply both the emergency load and the firefighting load, especially the firefighting load to the end. However, in order to save construction costs, emergency power generators in apartment, commercial, and business buildings can satisfy only one of the required loads. In cases like this, when a power outage and a fire occur simultaneously, there is a danger of firefighting equipment not operating due to insufficient power supply from the emergency generator. Therefore, an EPS must have a reserved firefighting power that can supply both the firefighting and the emergency load. Such EPS, when faced with a danger of an overload, will shut down the supply to all or part of the emergency load, thus securing a continuous power supply to the firefighting equipment. The generator power system with reserved firefighting power (RFP) will also have an indicator to show that the selective control is being used. General power generation systems for emergency load and firefighting load were found to have a demand factor of 50-60% with a lump. However, when installing an EPS, the builders must choose the higher demand factor suggested according to the official approval demand factor of the building.

• 한국화재소방학회논문지
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• 제26권3호
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• pp.29-34
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• 2012

본 논문에서는 소방전원 및 소방전원 부족시 용량 보완을 위한 인터록 시스템의 한계점 등을 분석하고 소방전원 보존형 발전기(RFP)의 작동방법 등을 제시하여 화재와 같은 상황에 효율적으로 대응할 수 있는 방법을 제시하는데 있다. 소방전원보존형 발전기에서 일괄제어방식은 발전기에 과부하가 걸리면 소방전원보존용 제어기에서 신호를 발신하여 소방부하는 남겨두고 비상부하용 주차단기를 일괄 차단하고, 발전기가 마지막까지 소방부하에 전원이 공급되도록 한 시스템이다. 순차제어방식은 과부하가 걸리면 소방전원보존용 제어기에서 1차 신호를 발신하여 설정된 비상부하의 1단계 부하를 차단한다. 그리고 지속적인 감시 상태에서 소방부하가 증가하여 발전기가 다시 과부하가 걸리면 제어기에서 2차 신호가 발신하여 비상부하의 2단계 부하를 차단하는 시스템이며 각각의 작동 상태를 표시하는 표시장치를 가진다.

• Earthquakes and Structures
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• 제22권2호
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• pp.137-145
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• 2022

As steel is highly sensitive to temperature variations, fire exposure is more destructive in the case of steel structures in comparison to the concrete ones. The performance of an intermediate three-story steel moment frame with 4 spans was studied under the service load, thermal load and post-earthquake fire in this paper. Also, the effects of passive fire-protection materials such as ordinary cement-based and fire-retardant coatings were investigated. To model and analyze the structure; Abaqus software is utilized. In order to apply the earthquake effect, the push-over analysis method is employed. Changes in the stories deflection, endurance time and growth of nonlinear regions due to losses in the steel stiffness and strength, are among the issues considered in this study. As an interesting finding, the beams protected by ordinary cement-based coating could sustain the fire exposure at least for 30 minutes in all cases. The mentioned time is increased by employing a new fire-retardant protection, which could prevent significant loss in the structure resistance against fire, even after 60 minutes of exposure to fire.

• 한국재난정보학회 논문집
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• 제17권2호
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• pp.351-364
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• 2021

연구목적: 교육시설 화재위험성 평가를 위한 기초 데이터 확보를 위하여 화재하중 분석하였다. 사전조사로 화재하중을 산정하기 위해 학교시설의 화재하중과 관련된 기초자료를 수집하였다. 연구방법: 기초자료는 화재하중의 정의 및 종류, 화재하중 산정을 위한 연소열 데이터 화재하중에 대한 선행연구를 통하여 진행하였고 화재하중 산출시 구획실에 존재하는 가연물 중량에 해당 연소열을 곱하여 산정하였다. 연구결과: A 초등학교의 고정가연물은 교실, 음악실, 교무실은 정서나 안전을 고려하여 바닥이 주로 목재로 이루어져 있었으며, 나머지 구획실은 석재로 이루어졌다. 천장과 벽은 석고보드, 콘크리트로 되어있어 가연물에 속하지 않았다. 각 실별로 대표적인 적재가연물은 교실은 책상, 의자, 사물함 등으로 나타났으며 과학실은 실험기구함, 실험도구함이 주를 이루어었으며 도서실은 책과 서가, 열람기구 등이 큰 비중을 차지하였다. 결론: A 초등학교의 적재가연물에 따른 적재화재하중은 도서실, 컴퓨터실, 영어학습실, 교무실, 일반교실, 과학관, 음악실의 순으로 나타났다.

• Steel and Composite Structures
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• 제14권3호
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• pp.295-312
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• 2013

In this paper, a simplified approach based on critical temperature for fire resistance design of steel-concrete composite beams is proposed. The method for determining the critical temperature and fire protection of the composite beams is developed on the basis of load-bearing limit state method employed in current Chinese Technical Code for Fire safety of Steel Structure in Buildings. Parameters affecting the critical temperature of the composite beams are analysed. The results show that at a definite load level, section shape of steel beams, material properties, effective width of concrete slab and concrete property model have little influence on the critical temperature of composite beams. However, the fire duration and depth of concrete slab have significant influence on the critical temperature. The critical temperatures for commonly used composite beams, at various depth of concrete and fire duration, are given to provide a reference for engineers. The validity of the practical approach for predicting the critical temperature of the composite beams is conducted by comparing the prediction of a composite beam with the results from some fire design codes and full scale fire resistance tests on the composite beam.

• Structural Engineering and Mechanics
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• 제32권5호
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• pp.635-648
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• 2009

This paper describes fire performance of eight axially restrained reinforced concrete (RC) columns under a combination of two different load ratios and two different axial restraint ratios. The eight RC columns were all concentrically loaded and subjected to ISO834 standard fire on all sides. Axial restraints were imposed at the top of the columns to simulate the restraining effect of the rest of the whole frame. The axial restraint was effective when the column was expanding as well as contracting. As the results of the experiments have shown, the stiffness of the axial restraint and load level play an important role in the fire behaviors of both HSC and NSC columns. It is found that (a) the maximum deformations during expanding phase were influenced mostly by load ratio and hardly by axial restraint ratio, (b) For a given load ratio, axial restraint ratio had a great impact on the development of axial deformation during contraction phase beyond the initial equilibrium state, (c) increasing the axial restraint increased the value of restraint force generated in both the NSC and HSC columns, and (d) the development of column axial force during the contracting and cooling phase followed nearly parallel trend for columns under the same load ratio.

• 한국화재소방학회논문지
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• 제25권1호
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• pp.63-71
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• 2011

비대칭 H형강을 활용한 슬림플로어의 경우, 상대적으로 열전달 속도가 낮은 콘크리트에 강재가 매립된 형상으로 설계되어 화재조건에서 강재의 강성저하를 최소화 할 수 있는 형상으로 설계되었다. 그러나 비대칭 H형강의 하부플렌지는 화재에 직접적으로 노출되므로, 이 부분에 대한 내화피복을 적용하여 슬림플로어 보의 내화성능을 최대한 확보할 수 있는 방안을 모색하고자 하였다. 실험계획은 재하 하중비 0.4와 0.3을 조정하여 하중조건에 따른 내화성능을 비교하고자 하였고 철근보강에 따른 내화성능 향상효율, 내화피복을 적용하였을 경우의 180분 내화성능 확보 유 무를 분석하고자 실험을 수행하였다. 하중비 변화에 따른 실험체를 비교한 결과, 0.1 의 하중비를 낮출 경우 내화성능은 12분 차이가 나며, 처짐격차는 39mm였다. 철근보강에 따른 영향은 12분정도의 내화성능 향상이 가능하며, 최대 102.4mm의 처짐이 제어된다.

• 한국강구조학회 논문집
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• 제27권4호
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• pp.387-397
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• 2015

국내의 내화성능평가는 대부분 사양적설계 방법인 품질시험을 통해 이뤄지고 있다. 하지만 시험 특성상 많은 비용과 시간을 요구하며 다양한 건축구조에 대한 내화성능평가에는 어려움이 많다. 따라서 본연구에서는 성능적 설계를 위한 연구로 유한요소 구조해석 프로그램인 ABAQUS를 사용해 H형강 휨재를 대상으로 변수에 따른 열응력 해석을 통해 내화성능을 검토하며, 하중비별 한계온도를 제안한다.