• 한국공간구조학회논문집
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• 제17권1호
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• pp.69-75
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• 2017

In fire design for floors, the three criteria of stability, integrity and insulation are required for the specified fire resistance duration. Among these, stability is not easy to confirm. For solid prestressed concrete slabs of uniform thickness, Eurocode 2 provides tabulated data and specifies an axis distance to the centroid of strands to achieve particular fire resistance ratings, but it is not clear if this data can be used for a wide range of different prestressed slab profiles. In order to verify the current code-fire ratings for precast prestressed slabs, both simple and advanced calculation methods are investigated. This paper examines the use of calculation methods, accounting for the real behaviour of unprotected simply supported prestressed concrete slabs exposed to the standard ISO 834 fire. The calculated fire resistance of each prestressed concrete slab is compared with tabulated data in Eurocode part 1.2, with detailed discussion.

• Steel and Composite Structures
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• 제17권6호
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• pp.835-850
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• 2014

The fire resistance of composite steel and concrete structures may be determined by using the simplified methods provided in EN 1994-1-2. For the particular situations not covered by the standard, an advanced calculation model might be applied, using special purpose programs for the analysis of structures in fire. The validation of these programs has always been an important issue for software developers, but also for designers and authorities. Clause 4.4.4 from EN 1994-1-2 refers to the validation of the advanced calculation models and states that these models must be validated through relevant test results. The paper presents the calculation of fire resistance of the composite columns in a high-rise building built in Romania, and focusses on the validation of the calculation model (computer program SAFIR), for this particular case. This validation, asked by the Romanian authorities, considers the available experimental results of a fire test, performed on a similar composite steel-concrete column.

• 대한금속재료학회지
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• 제49권9호
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• pp.671-677
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• 2011

Steel columns used in steel buildings are inclined to lose their strength when exposed to severe fire conditions, so fire resistance is required in most countries to protect against loss of life and building collapses. In Korea, the fire resistance of columns can be obtained by the fire test defined in KS F 2257-1, 7. The fire resistance of a steel column should be evaluated in terms of the column's conditions, such as various section types (H-section, hollow-section), the column's length and boundary conditions, and whether it is fixed or hinged. However, fire testing of steel columns is usually conducted on one standard-sized H-section over 3,000 mm, and the result is used as the column's fire resistance. This is not a reasonable way to ensure that a building can withstand fire conditions. In this study, to evaluate the possibility of calculating the fire resistance of steel columns with material properties of high tensile strength of SS 400, both load-bearing fire tests and calculation of steel temperatures were carried out. The results of temperature calculation were very similar to those obtained by fire test.

• Steel and Composite Structures
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• 제13권2호
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• pp.171-185
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• 2012

The calculation of fire resistance for a composite structural element comprises the calculation of the temperature within its cross-section and of the load bearing capacity, considering the evolution of the steel and concrete mechanical properties, function of the temperature. The paper proposes a method to calculate the bending capacity under ISO fire, for Slim Floor systems using asymmetric steel beams, with a wider lower flange or a narrow upper flange welded onto a half hot-rolled profile. The temperatures in the cross-section are evaluated by means of empirical formulas determined through a parametrical analysis, performed with the special purpose non-linear finite element program SAFIR. Considering these formulas, the bending capacity may be calculated, using an analytical approach to determine the plastic bending moment, for different fire resistance demands. The results obtained with this simplified method are validated through numerical analysis.

• 국제초고층학회논문집
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• 제2권1호
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• pp.23-30
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• 2013

This paper explains the Japanese present situations relevant to the fire resistance performance. Performance-based fire provisions was introduced in 1998 for the first time when the Building Standard Law was amended. However, performance-based fire resistance design had been used since long before the official introduction of performance-based provisions. A Comprehensive Technology Development Project of Ministry of Construction from 1982 to 1986 established a technical basis for performance-based fire safety engineering in Japan. A system of calculation methods for fire resistance verification was prescribed in the Ministry Notification in 2000 utilizing the results of this project as a background. This method, referred to as the Fire Resistance Verification Method (FRVM), is the standard method to verify the fire resistance performance of principal building parts such as columns, beams, and walls of steel, concrete, or wood structured buildings. For tall buildings, however, more advanced method for performance verification is often necessary because new building materials or structural systems are often used for these buildings. An example project of tall building owned by a major newspaper company is presented in this paper. Advanced thermal deformation analysis is executed to secure the fire resistance of the building.

• 한국화재소방학회논문지
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• 제24권2호
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• pp.31-37
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• 2010

비대칭 슬림플로어 합성보(Asymmetric Slimfloor Beam, 이하 ASB)는 비대칭 형강의 일부를 콘크리트 슬래브에 삽입한 합성보로서, 유럽에서 개발되었다. 근래 국내에서도 건축물의 층고저감, 물량감소, 내화 성능 증대 등의 목적으로 ASB의 연구가 진행되고 있다. 본 연구에서는 실험을 통하여 ASB의 내화성능을 확인하고, 열전달해석을 통하여 내화성능 시간에서의 모멘트 내력(Moment capacity)을 산정하였다. 그 결과를 바탕으로 방화석고보드와 ASB로 구성된 3시간 내화구조를 선정하고, 내화 성능을 검토하였다.

• 한국강구조학회 논문집
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• 제21권1호
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• pp.27-35
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• 2009

주요 철골구조체는 일정한 시간동안 내화성능을 발휘하기 위한 내화조치를 필요로 한다. 본 연구는 철골기둥의 내화피복 국내인정 제품의 내화성능을 분석 평가함을 목적으로 한다. 대상제품은 보드피복과 뿜칠피복 두 종류의 제품을 대상으로 하여 샘플연구를 하였다. 국내기준과 유럽기준에 기초하여 제품의 내화성능을 분석하였다. 또한 국내기준을 유럽기준의 성능설계관점에서 분석 고찰하였다. 온도적 측면에서 국내기준의 내화성능은 일반적으로 안전하다고 사료되지만, 재료의 물성치 자료확충, 강재온도 산정방법, 프로필계수, 화재시 내력검증 등의 특성을 반영할 필요가 있다고 사료된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.59-60
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• 2020

Large fires continue to spread throughout the building, including the fire in Uijeongbu in 2015, the fire in Jecheon in 2017, and the fire in Miryang in 2018. According to the above fire case investigation, major problems were the fire resistance performance of compartment members such as fire doors, the fire spread due to damage to exterior wall openings, and smoke spread through vertical openings. However, in South Korea, only specification design is implemented for buildings that are not subject to performance design. In addition, the analysis of the fire resistance performance standards of building members in the specification design showed that fire doors were not specified in detail for 60 minutes of insulation performance and 60 minutes of fire resistance performance of E/V doors, limiting the prevention of fire spread. Therefore, the purpose of this research is to prepare measures to prevent the spread of fire by presenting simple transplants for calculating the required fire time according to the architectural design conditions for the performance design of the components of the fire room according to the purpose of use of the front of the building.

• Structural Engineering and Mechanics
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• 제12권5호
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• pp.559-572
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• 2001

A numerical model, in the form of a computer program, for evaluating the fire resistance of insulated wide-flange steel columns is presented. The three stages associated with the thermal and structural analysis in the calculation of fire resistance of columns is explained. The use of the computer program for tracing the response of an insulated steel column from the initial pre-loading stage to collapse, due to fire, is demonstrated. The validity of the numerical model used in the program is established by comparing the predictions from the computer program with results from full-scale fire tests. Details of fire tests carried out on wide-flange steel columns protected with ceramic fibre insulation, together with results, are presented. The computer program can be used to evaluate the fire resistance of protected wide-flange steel columns for any value of the significant parameters, such as load, section dimensions, column length, type of insulation, and thickness of insulation without the necessity of testing.

• Structural Engineering and Mechanics
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• 제62권6호
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• pp.663-674
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• 2017

This paper presents an approach for evaluating performance of prestressed concrete (PC) bridge girders exposed to fire. A finite element based numerical model for tracing the response of fire exposed T girders is developed in ANSYS. The analysis is carried out in three stages, namely, fire temperature calculation, cross sectional temperature evaluation, and then strength, deformation and effective prestress analysis on girders exposed to elevated temperatures. The applicability of the computer program in tracing the response of PC bridge girders from the initial preloading stage to failure stage, due to combined effects of fire and structure loading, is demonstrated through a case study, and validated by test data of a scaled PC box girder under ISO834 fire condition. Results from the case study show that fire severity has a significant influence on the fire resistance of PC T girders and hydrocarbon fire is most dangerous for the girder. The prestress loss caused by elevated temperature is about 10% under hydrocarbon fire till the girder failure, which can lead to the increase in deflection of the PC girder. The rate of deflection failure criterion is suggested to determine the failure of PC T girder under fire.