PREDICTION OF RESIDUAL STRENGTH OF COMPOSITE COLUMNS USING FEM ANALYSIS

Fires in buildings cause not only economic losses but also many casualties. A prolonged fire involves the possibility of the damage to structural members, which calls for the repair or reinforcement of the building. Since it is critical to decide whether structural members need reinforcement, the technique to determine the degree of the damage to structural members caused by a fire should be established. CFT columns are superior to generic steel columns in terms of fire resistance performance thanks to the thermal storage effect of the concrete inside the columns. Studies have suggested how to reinforce the concrete to further improve the structural strength and fire resistance performance of CFT columns. When CFT columns of a building are damaged by a fire, it is required to determine preciously how serious the structural deterioration of the members is. The purpose of this study is to evaluate the residual strength of CFT columns damaged by a fire by evaluating the temperature distribution inside the columns and determining the degree of deterioration in the load capacity of concrete and steel in relation to temperature distribution.

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Study on the Data-Bases for Fire Engineering Design of Structural Steels Members

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.628.156 ◽

2012 ◽

Vol 628 ◽

pp. 156-160

Author(s):

In Kyu Kwon ◽

Hyung Jun Kim ◽

Heung Youl Kim ◽

Bum Yean Cho ◽

Kyung Suk Cho

Keyword(s):

Bearing Capacity ◽

Fire Resistance ◽

Engineering Method ◽

Fire Tests ◽

Structural Members ◽

Data Bases ◽

Load Bearing Capacity ◽

Load Bearing ◽

In Fire ◽

Resistance Performance

Structural steel has been used since the early 1970’s in Korea as primary structural members such as columns, beams, and trusses. The materials have much higher strength such as fast construction, high load bearing capacity, high construction quality but those have a fatal weakness as well. Load-bearing capacity is going down when the structural members are contained in fire condition. Therefore, to protect the structural members made of steels from the heat energy the fire resistance performance required. Generally, the fire resistance performance have evaluated from the exact fire tests in fire furnaces. But the evaluation method takes much more time and higher expenses so, the engineering method requires. The engineering method not only adopts a science but also an engineering experience. In this paper, to make various data-bases for evaluation of structural members such as columns(H-section, RHS), beams, loaded fire tests were conducted and derived not only each limiting temperature but also fire resistance respectively.

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Comparison Study of Structural Stabilities for H-Section Columns Built with Ordinary Grade Strength Structural Steels According to Boundary Conditions and Lengths at High Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.937.424 ◽

2014 ◽

Vol 937 ◽

pp. 424-427

Author(s):

In Kyu Kwon

Keyword(s):

Boundary Condition ◽

High Temperature ◽

Boundary Conditions ◽

Fire Resistance ◽

Structural Steels ◽

Structural Members ◽

Steel Buildings ◽

Standard Fire ◽

Fire Curve ◽

Resistance Performance

Fire resistance performance of structural members has been evaluated from each singular section and standard fire curve since the beginning of fire tests. However, the need of the exact fire resistance of H-section columns applied in the steel buildings has increased. The main reason for this is there is a difference between the conditions being conducted during the fire test and that from real situation. In this paper, the structural stability of H-section column made of an ordinary strength grade structural steels, SS 400, SM 400, and SM 490 at high temperature were evaluated and compared with boundary conditions and column’s length. This was done in order to suggest a new guideline for the application of fire protective materials in steel column in which the boundary conditions and column lengths are different from that tested with hinge to hinge and 3500 mm. The findings from this study showed hinge to hinge boundary condition was more conservative. And fire resistance performance of longer columns in the case of hinge to fixed and fixed to fixed boundary condition than from 3500 mm and hinge to hinge boundary condition can sustain at high temperature without adding fire protective materials.

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Experimental Study on the Fire Resistance of Rectangular Hollow Sections Steel Columns

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.112 ◽

2012 ◽

Vol 557-559 ◽

pp. 112-115

Author(s):

In Kyu Kwon ◽

Heung Youl Kim ◽

Hyung Jun Kim

Keyword(s):

Engineering Design ◽

Fire Resistance ◽

Scientific Method ◽

Maximum Temperature ◽

Structural Elements ◽

Structural Members ◽

Building Collapse ◽

Steel Columns ◽

Fire Engineering ◽

Limiting Temperatures

A fire occurring at a building causes severe damages to its structural members and brings unexpected collapse. Therefore, the building regulation of each nation has to define fire resistance to prevent building collapse due to high temperatures. In general, the fire resistance of each structural member can be evaluated by two methods. One is prescriptive method that is guided by a specific building regulation containing fire resistance examples or by the application of new examples tested fire experimental procedures. The other is performance based fire engineering design. Being an engineered and scientific method, it utilizes the results obtained from the calculation of fire severities, temperatures of members and so on. The easiest way to evaluate the fire resistance of a steel member is to compare its limiting temperature and maximum temperature. Therefore, constructing the database of the limiting temperatures of structural elements is very important in performance based fire engineering design. This paper is to derive the fire resistance and limiting temperatures of rectangular hollow sections under loads.

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Fire Resistance Evaluation of Reinforced Concrete Columns Using Axial Load Ratio and Slenderness Ratio

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.905.268 ◽

2014 ◽

Vol 905 ◽

pp. 268-272

Author(s):

In Hwan Yeo ◽

Bum Yean Cho ◽

Jae Hong An ◽

Byung Youl Min

Keyword(s):

Fire Resistance ◽

Axial Load ◽

Slenderness Ratio ◽

Load Ratio ◽

Cost Effective ◽

Concrete Columns ◽

Accurate Estimation ◽

Structural Members ◽

Standard Fire ◽

Resistance Performance

Since the column members in buildings deal with both vertical and horizontal loads, appropriated amount of load should be estimated in order to evaluate the fire resistance performance of the columns under loaded condition. However, according to the ISO 834, the international standard for the evaluation of structural members, the fire resistance performance evaluation of column members is only based on the displacement and displacement rate under loaded condition in a standard fire. The purpose of this study is to suggest appropriate axial load ratios for the evaluation of fire resistance performance. The test conducted in this study produced appropriate axial load ratios for different slenderness ratios. They are expected to contribute to more accurate estimation of fire resistance performance and more efficient and cost-effective structural design.

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Properties of Concrete at Elevated Temperatures

ISRN Civil Engineering ◽

10.1155/2014/468510 ◽

2014 ◽

Vol 2014 ◽

pp. 1-15 ◽

Cited By ~ 153

Author(s):

Venkatesh Kodur

Keyword(s):

Fire Resistance ◽

Elevated Temperatures ◽

Mechanical Deformation ◽

Structural Members ◽

Fire Response ◽

Key Characteristics ◽

Deformation Properties ◽

Different Types ◽

Resistance Performance

Fire response of concrete structural members is dependent on the thermal, mechanical, and deformation properties of concrete. These properties vary significantly with temperature and also depend on the composition and characteristics of concrete batch mix as well as heating rate and other environmental conditions. In this chapter, the key characteristics of concrete are outlined. The various properties that influence fire resistance performance, together with the role of these properties on fire resistance, are discussed. The variation of thermal, mechanical, deformation, and spalling properties with temperature for different types of concrete are presented.

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Elastomer Spacers in Fire Conditions

Civil and Environmental Engineering Reports ◽

10.1515/ceer-2017-0039 ◽

2017 ◽

Vol 26 (3) ◽

pp. 109-119

Author(s):

Paweł Roszkowski ◽

Bartłomiej Sędłak ◽

Paweł Sulik

Keyword(s):

Thermal Degradation ◽

Fire Resistance ◽

Load Capacity ◽

Combustible Material ◽

Cavity Depth ◽

Standard Fire ◽

Degradation Rates ◽

In Fire ◽

Resistance Performance ◽

Fire Conditions

Abstract In the paper, fire resistance of linear joints seal made of elastomer spacers under standard fire conditions, and thermal degradation range of EPDM elastomeric spacers are investigated. The geometry of elastomer spacer joints is important not only for their load capacity under normal conditions - thickness, width, and cavity depth can also influence fire resistance performance. Linear joints of different thicknesses and widths have been tested. The fire insulation and fire integrity were verified for various arrangements. Relatively low thermal degradation rates have been measured, given that EPDM is a combustible material.

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Influence of Brick Walls on the Temperature Distribution in Steel Columns in Fire

Acta Polytechnica ◽

10.14311/1077 ◽

2009 ◽

Vol 49 (1) ◽

Author(s):

António J. P. Moura Correia ◽

Joao Paulo C. Rodrigues ◽

Valdir Pignatta e Silvac

Keyword(s):

Finite Element ◽

Temperature Distribution ◽

Fire Resistance ◽

Experimental Models ◽

Finite Element Program ◽

Steel Columns ◽

Element Program ◽

The University ◽

In Fire ◽

Resistance Tests

This paper reports on a study of steel columns embedded in walls in fire. Several fire resistance tests were carried out at the Laboratory of Testing Materials and Structures of the University of Coimbra, in Portugal. The temperatures registered in several points of the experimental models are compared with those obtained in numerical simulations carried out with the SUPERTEMPCALC finite element program.

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Case Study on Prediction of Temperature in Compartment Considering Fire Conditions in Buildings

Korean Society of Hazard Mitigation ◽

10.9798/kosham.2021.21.4.61 ◽

2021 ◽

Vol 21 (4) ◽

pp. 61-68

Author(s):

Gyuhwan Cho ◽

Jaekwon Ahn

Keyword(s):

Case Studies ◽

Fire Resistance ◽

Structural Member ◽

Structural Members ◽

Simulation Results ◽

Resistance Performance ◽

Fire Conditions ◽

Room Corner Test

Current fire resistance standards for major structural members of buildings require uniform fire resistance performance (in hours). However, buildings may be vulnerable to various local-fire conditions, depending on the industry or business, so it is necessary to examine their differences through simulations. In this study, the existing room corner test (KSF ISO 9705) and simulation results were compared to verify the reliability of the simulations. Next, the similarity of the results was identified. Simulations of actual buildings were performed based on local-fire conditions, and it was verified that the temperature varies by location. Based on the results, it is necessary to focus on performance-based fire resistance design rather than the specification-based design, which requires uniform fire resistance performance in hours. Simulation case studies should be conducted to reflect the diversity of the fire and structural member conditions.

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