• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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• pp.82-89
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• 2014

In this paper, fire resistance test was carried out to obtain class H-120 thermal insulation of fire dampers according to a hydrocarbon fire conditions. Specimens were fabricated three different types according to the change of the insulation system applied to damper blade and coaming which were measured surface temperature by performing the fire resistance test. As a test result, specimen-1, 2 of an uninsulated damper blade were exceeded thermal insulation acceptance criteria at 21 minutes, 46 minutes respectively, but specimen-3 of an insulated damper blade was satisfied thermal insulation acceptance criteria during 120 minutes. The test results showed that the insulation of the damper blade was an important factor in the fireproof performance of fire dampers concerning the coaming length minimum 500 mm on the unexposed side as specified test standard.

• Structural Engineering and Mechanics
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• v.7 no.2
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• pp.127-145
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• 1999

This paper deals with the development of an approach for evaluating the squash load and rigidity of unprotected concrete filled steel columns at elevated temperatures. The current approach of evaluating these properties is reviewed. It is shown that with a non-uniform temperature distribution, over the composite cross-section, the calculations for the squash load and rigidity are tedious in the current method. A simplified approach is proposed to evaluate the temperature distribution, squash load, and rigidity of composite columns. This approach is based on the model in Eurocode 4 and can conveniently be used to calculate the resistance to axial compression of a concrete filled steel column for any fire resistance time. The accuracy of the proposed approach is assessed by comparing the predicted strengths against the results of fire tests on concrete filled circular and square steel columns. The applicability of the proposed approach to a design situation is illustrated through a numerical example.

• Steel and Composite Structures
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• v.36 no.6
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• pp.657-669
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• 2020

This study investigates the fire resistance characteristics of reactive powder concrete according to changes in the cement content per unit area, mixing ratio of metakaolin (MK), and content of polypropylene fiber. A fire test was conducted, and the resulting residual strength characteristics were investigated through flexural and compressive strength measurements, as well as condition rating classification based on visual evaluation. MK effectively reduced the initial high content of calcium hydroxide, thereby reducing the water vapor pressure generated during pyrolysis and slowing spalling. Furthermore, the pore structure and loose tissue were effective for relieving the water vapor pressure in the event of a fire.

• Journal of Korean Association for Spatial Structures
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• v.16 no.4
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• pp.53-58
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• 2016

SLIM AU(A plus U-shaped) composite beam was developed for reducing the story height in the residential buildings, and saving the cosrtuction cost of floor structures. Structural performance and economic feasibility of the composite beam have been sufficiently approved through the structural experiments and the analytical studies. However, the verification for fire safety is necessary for the practical application of the composite beam. The fire resistance tests with and without loading were performed for the fire safety verification, and the test results were summarized in this paper.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.481-484
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• 2005

Recently, Since the advanced nano technology develops unique physical and chemical properties different from those of the conventional materials. Normal concretes mixed with nano size materials have been studied to improve the fire-resistance with high strength and lower heat conductivity. In this pilot study, the nano-particle contents in the specimens ($\Phi$10\times20 cm$) were 0, 2, 4, and 6$\%$ by weight of cement, and fire-temperatures 800$^{circ}C$ was considered. The results show that as the nano-particle contents increases, fire resistance of concrete are superior to those of the ordinary concrete. Also, the experimental results show that fire resistance of nano Aluminum hydroxide dispersed concrete are superior to those of the nano-SiO2 concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.118-119
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• 2014

A fire in a steel framed building can decrease a structural stability and cause deformation. And the fire continues the building can be demolished. Therefore, every country requires fire resistance performance of structural elements. In case of column, fire protective thickness derived from a specific fire test using an horizontal furnace is allowed to apply any kinds of sections and lengths of column. However, the lengths and sections of the column in steel framed buildings are various. In this paper, to know the differences of fire performance of steel column according to variance of lengths, a maximum allowable stress, steel surface temperature history, deflection are calculated and the thickness of fire protective material for longer column(4700 mm) need to enforce about 10% more than shorter column (3500 mm).

• Fire Science and Engineering
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• v.22 no.2
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• pp.84-90
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• 2008

This paper aims to experimentally investigate the in-fire performance of composite beams with respect to the effects of load ratio and shear interaction. Under a Standard ISO834 fire, the development of temperature and deflection of simply supported composite beams were recorded. In particular, the transition of temperature distribution across the cross-section. The fire resistance of composite beam was interpreted regarding the level of shear interaction.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.96-97
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• 2021

In the Building Act, performance-based fire safety design is being promoted for institutionalization. The behavior of the structure against fire conditions can be predicted by using the advanced numerical analysis method based on the FEM (Finite Element Method) to predict the entire structural behavior including the behavior of the structure, but there is a limit to expressing the fire properties of the space and predicting the fire properties It is difficult to determine the variables to be transmitted to the FEM (Finite Element Method) model from the fire simulation results using FDS (Fire Dynamics Simulator). Accordingly, the purpose of this study is to introduce the code user's manual for FDS and FEM unidirectional coupling analysis.

• Journal of the Korea Institute of Building Construction
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• v.16 no.6
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• pp.513-518
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• 2016

This study evaluates the fire resistance performance for 60MPa high strength concrete reinforced by recycling polyethylene-terephthalate(PET) fiber(fiber content : 0.05 vol.%). Because there is no fire resistance test results for circular concrete column, a fire resistance test was carried out for circular concrete column specimens. As a result, it was confirmed that PET fiber was effective against the spalling control of high strength concrete. However, the specimen with cover thickness 30mm did not satisfy the temperature standard of main reinforcement, and the specimen with cover thickness 40mm satisfied the temperature standard of main reinforcement. Therefore, more than 40mm cover thickness was demanded for stable fire resistance performance.

• Coupled systems mechanics
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• v.9 no.2
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• pp.163-182
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• 2020

Coupled thermo-mechanical analysis of reinforced concrete slab at elevated temperatures from a fire accounting for nonlinear thermal parameters is carried out. The main focus of the paper is put on a one-way continuous reinforced concrete slab exposed to fire from the single (bottom) side as the most typical working condition under fire loading. Although contemporary techniques alongside the fire protection measures are in constant development, in most cases it is not possible to avoid the material deterioration particularly nearby the exposed surface from a fire. Thereby the structural fire resistance of reinforced concrete slabs is mostly influenced by a relative distance between reinforcement and the exposed surface. A parametric study with variable concrete cover ranging from 15 mm to 35 mm is performed. As the first part of a one-way coupled thermo-mechanical analysis, transient nonlinear heat transfer analysis is performed by applying the net heat flux on the exposed surface. The solution of proposed heat analysis is obtained at certain time steps of interest by α-method using the explicit Euler time-integration scheme. Spatial discretization is done by the finite element method using a 1D 2-noded truss element with the temperature nodal values as unknowns. The obtained results in terms of temperature field inside the element are compared with available numerical and experimental results. A high level of agreement can be observed, implying the proposed model capable of describing the temperature field during a fire. Accompanying thermal analysis, mechanical analysis is performed in two ways. Firstly, using the guidelines given in Eurocode 2 - Part 1-2 resulting in the fire resistance rating for the aforementioned concrete cover values. The second way is a fully numerical coupled analysis carried out in general-purpose finite element software DIANA FEA. Both approaches indicate structural fire behavior similar to those observed in large-scale fire tests.