• 한국해양공학회지
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• 제35권3호
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• pp.203-215
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• 2021

Current industrial practices and approaches are simplified and do not describe the actual behavior of plated elements of offshore topside structures for safety design due to fires. Therefore, it is better to make up for the defective methods with integrated fire safety design methods based on fire resistance characteristics such as residual strength capacity. This study numerically investigates the residual strength of steel stiffened panels exposed to hydrocarbon jet fire. A series of nonlinear finite element analyses (FEAs) were carried out with varying probabilistic selected exposures in terms of the jet fire location, side, area, and duration. These were used to assess the effects of exposed fire on the residual strength of a steel stiffened panel on a ship-shaped offshore structure. A probabilistic approach with a feasible fire location was used to determine credible fire scenarios in association with thermal structural responses. Heat transfer analysis was performed to obtain the steel temperature, and then the residual strength was obtained for the credible fire scenarios under compressive axial loading using nonlinear FEA code. The results were used to derive closed-form expressions to predict the residual strength of steel stiffened panels with various exposure to jet fire characteristics. The results could be used to assess the sustainability of structures at risk of exposure to fire accidents in offshore installations.

• International Journal of Internet, Broadcasting and Communication
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• 제16권2호
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• pp.237-246
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• 2024

In recent years, the frequent occurrence of fire accidents in university libraries has posed significant threats to the safety of students' lives and property, alongside negative social impacts. Accurately analyzing the factors affecting evacuation during library fires and proposing optimized measures for safe evacuation is thus crucial. This paper utilizes a specific university library as a case study, simulating fire evacuation scenarios using the Pathfinder software, to assess and validate evacuation strategies and propose relevant optimizations. Pathfinder, developed by Thunderhead Engineering in the United States, is an intuitive and straightforward personnel emergency evacuation assessment system, offering advanced visualization interfaces and 3D animation effects. This study aims to construct evacuation models and perform simulation analysis for the selected university library using Pathfinder. The library's structural layout, people flow characteristics, and the nature of fire and smoke spread are considered in the analysis. Additionally, evacuation scenarios involving different fire outbreak locations and the status of emergency exits are examined. The findings underscore the importance of effective evacuation in fire situations, highlighting how environmental conditions, individual characteristics, and behavioral patterns significantly influence evacuation efficiency. Through these investigations, the study enhances understanding and optimization of evacuation strategies in fire scenarios, thereby improving safety and efficiency. The research not only provides concrete and practical guidelines for building design, management, and emergency response planning in libraries but also offers valuable insights for the design and management of effective evacuation systems in buildings, crucial for ensuring occupant safety and minimizing loss of life in potential hazard situations

• 대기
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• 제22권1호
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• pp.47-55
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• 2012

The characteristics of flow and pollutant dispersion for fire scenarios in an urban area are numerically investigated. A computational fluid dynamics (CFD) model coupled to a mesoscale weather research and forecasting (WRF) model is used in this study. In order to more accurately represent the effect of topography and buildings, the geographic information system (GIS) data is used as an input data of the CFD model. Considering prevailing wind, firing time, and firing points, four fire scenarios are setup in April 2008 when fire events occurred most frequently in recent five years. It is shown that the building configuration mainly determines wind speed and direction in the urban area. The pollutant dispersion patterns are different for each fire scenario, because of the influence of the detailed flow. The pollutant concentration is high in the horse-shoe vortex and recirculation zones (caused by buildings) close to the fire point. It thus means that the potential damage areas are different for each fire scenario due to the different flow and dispersion patterns. These results suggest that the accurate understanding of the urban flow is important to assess the effect of the pollutant dispersion caused by fire in an urban area. The present study also demonstrates that CFD model can be useful for the assessment of urban environment.

• Steel and Composite Structures
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• 제51권2호
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• pp.127-138
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• 2024

In this paper, structural behavior under fire conditions is comprehensively examined, and a novel software interface for testing interfaces efficiently is developed and validated. In order to accurately assess the response of structures to fire scenarios, advanced simulation techniques and modeling approaches are incorporated into the study. This interface enables accurate heat transfer analysis and thermo-mechanical simulations by integrating software tools such as CSI ETABS, CSI SAP2000, and OpenSees. Heat transfer models can be automatically generated, simulation outputs processed, and structural responses interpreted under a variety of fire scenarios using the proposed technique. As a result of rigorous testing and validation against established methods, including Cardington tests on scales and hybrid simulation approaches, the software interface has been proven to be effective and accurate. The analysis process is streamlined by this interface, providing engineers and researchers with a robust tool for assessing structural performance under fire conditions.

• 대한안전경영과학회지
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• 제25권2호
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• pp.29-38
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• 2023

Social welfare facilities are used by a wide range of local residents, including vulnerable populations such as the elderly, children, and people with disabilities. During emergencies like fires, confusion can arise as these individuals try to evacuate. Evacuation simulation results have shown that utilizing evacuation systems based on specific evacuation scenarios can significantly decrease the time required for evacuation compared to general evacuation procedures. By anticipating potential fires based on changes in social and facility environments, appropriate evacuation scenarios can be developed and applied to evacuation systems, thus contributing to the safety and security of individuals during emergencies. In conclusion, for social welfare facilities that serve a large number of people, it is necessary to expand the focus on performance-based design depending on the size of the facility, and to continuously develop and train for appropriate evacuation scenarios that align with changing facility environments.

• 한국화재소방학회논문지
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• 제26권5호
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• pp.99-104
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• 2012

본 연구에서는 공동주택 화재 시 피난시나리오 및 화재실 배연개구부 유무에 따른 부속실 급기가압 시스템의 성능 및 효용성을 평가하기 위해 각 실의 압력변화 특성을 실험적으로 측정하였다. 그 결과, 화재실문과 계단실문 개폐 시나리오 및 배연개구부의 유무에 따라 압력변화 특성이 크게 달라졌으며 최저설계차압으로 재안정화 되기 전에 부속실 과압 또는 부압 발생, 도어클로져 닫힘 기능 저하 등의 현상이 나타났다. 또한. 급기댐퍼의 설치위치보다는 화재실 배연개구부의 존재가 규정방연풍속 유지에 필수적인 것으로 나타났다.

• Earthquakes and Structures
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• 제10권4호
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• pp.867-891
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• 2016

This paper addresses numerically the behavior of steel structures under Fire-after-Earthquake (FAE) loading. The study is focused on a four-storey library building and takes into account the damage that is induced in structural members due to earthquake. The basic objective is the assessment of both the fire-behavior and the fire-resistance of the structure in the case where the structure is damaged due to earthquake. The combined FAE scenarios involve two different stages: during the first stage, the structure is subjected to the ground motion record, while in the second stage the fire occurs. Different time-acceleration records are examined, each scaled to multiple levels of the Peak Ground Acceleration (PGA) in order to represent more severe earthquakes with lower probability of occurrence. In order to study in a systematic manner the behavior of the structure for the various FAE scenarios, a two-dimensional beam finite element model is developed, using the non-linear finite element analysis code MSC-MARC. The fire resistance of the structure is determined using rotational limits based on the ductility of structural members that are subjected to fire. These limits are temperature dependent and take into account the level of the structural damage at the end of the earthquake and the effect of geometric initial imperfections of structural members.

• 한국화재소방학회논문지
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• 제34권2호
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• pp.141-146
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• 2020

본 연구의 궁극적 목적은 소방활동 현장지휘관의 대응역량 강화이며, 그 일환으로 훈련용 콘텐츠 시나리오를 개발하였다. 현장지휘관의 상황판단력, 커뮤니케이션, 의사결정력을 3가지 핵심역량으로 설정하였다. 이 3가지 핵심역량이 시나리오 체계구성시 적극 반영될 수 있도록 구축하였다. 본 시나리오의 모든 내용은 재난현장 표준작전절차 SOP를 기반으로 구성하였다. 시나리오의 체계는 전체 14단계로 구성되며, 훈련의 시작과 마지막인 1단계와 14단계를 제외하면, 크게 4단계로 구분된다. 상황설정 단계와 1, 2, 3차 의사결정 단계로 구성되며, 특히 상황판단과 커뮤니케이션은 각 단계마다 중요한 요인이다.

• 국제초고층학회논문집
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• 제10권4호
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• pp.323-334
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• 2021

Concrete structures may rarely collapse in fire incidents but fire induced damage to structural members is inevitable as a result of material degradation and thermal expansion. This requires certain repairing measures to be applied to restore the performance of post-fire members. A brief review on investigation of post-fire damage of concrete material and concrete structural members is presented in this paper, followed by a review of post-fire repair research regarding various types of repairing techniques (FRP, steel plate, and concrete section enlargement) and different type of structural members including columns, beams, and slabs. Particularly, the fire scenarios adopted in these studies leading to damage are categorized as three levels according to the duration of gas-phase temperature above 600℃ (t₆₀₀). The repair effectiveness in terms of recovered performance of concrete structural members compared to the initial undamaged performance has been summarized and compared regarding the repairing techniques and fire intensity levels. The complied results have shown that recovering the ultimate strength is achievable but the stiffness recovery is difficult. Moreover, the current fire loading scenarios adopted in the post-fire repair research are mostly idealized as constant heating rates or standard fire curves, which may have produced unrealistic fire damage patterns and the associated repairing techniques may be not practical. For future studies, the realistic fire impact and the system-level structural damage investigation are necessary.

• 한국터널지하공간학회 논문집
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• 제12권6호
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• pp.429-441
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• 2010

본 연구에서는 뿜어붙임 방식의 모르타르 내화재가 시공된 침매터널 벽체구조물을 모사한 철근콘크리트 블록시험체에 대해 $HC_{inc}$ 화재시나리오와 IS0834(4시간) 화재시나리오 하에서 침매터널 내화재의 화재저항성 평가결과를 비교하였다. $HC_{inc}$ 화재시나리오 하에서는 내화재와 시험체 계면으로부터 0, 25, 50 mm 위치에서의 최대온도가 각각 $311^{\circ}C$, $194^{\circ}C$, $142^{\circ}C$로 나타났으며, IS0834(4시간) 화재시니리오 조건에서는 0, 25, 50 mm 위치에서의 최대온도가 각각 $332^{\circ}C$, $222^{\circ}C$, $179^{\circ}C$ 측정되었다. 이상의 결과로부터 본 연구에서 적용된 두 가지 화재시나리오들은 최대온도개념에서 유사한 화재강도임을 확인할 수 있었다. 이와 더불어 내화재 설치여부에 따른 침매터널 구조물의 안전성을 확인하기 위한 구조안정성 해석을 수행하였다. 이때 내화재가 설치되지 않은 시험체에 대한 화재시험을 수행하여 화재에 의한 콘크리트의 단면손실과 강도저하를 확인하고 그 결과를 이용하여 구조안정성 해석을 수행하였다. 이상의 해석 결과, 본 연구에서 적용된 강력한 화재시나리오 조건에서는 침매터널 구조물의 안정성 확보를 위하여 내화재가 필수적임을 확인할 수 있었다.