• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.4
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• pp.743-755
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• 2018

Tunnel is a semi-closed structure similar to underground space where the smoke generated from fire fills the space fast while escaping from the space slow. Because of such characteristics, when the fire breaks out by traffic accident, the vehicles are jammed making it difficult for the people to evacuate from the scene as well as for the fire engine to gain access to the scene. For such reasons, tunnels are globally categorized into some disaster classes for differentiated facilities and operation approaches. In Korea, less than a 1 km-long tunnel accounts for 80.0% and such a short tunnel which is categorized into Class III is not required to have smoke control system. In this study, a full-scale fire test was conducted in a bid to apply air curtain system using heat-resistant sirocco fan to a less than 1 km-long tunnel. To that end, heat resistance test to verify the normal operation at $250^{\circ}C$ for 60 minutes was conducted. Consequently, despite of rapid rising-temperature and increasing-carbon dioxide inside the air curtain (direction of fire in tunnel), initial condition was found to have been sustained outside the air curtain (opposite direction of fire in tunnel).

• Magazine of the Korea Concrete Institute
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• v.14 no.2
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• pp.30-36
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• 2002

콘크리트가 화재에 노출될 경우 가열에 의한 재질의 노화 및 열팽창에 의한 열응력의 발생에 따라 주요구조부인 기둥 및 보에 큰 손상이 생기게 되어 그 내력은 크게 저하하게 된다. 철근 콘크리트 구조물의 화재 상황을 조사해 보면 (그림 1)과 같이 열응력에 의한 기둥의 전단파괴, 보의 휨파괴 및 부재의 폭열 등이 보여진다.(중략)

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.3
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• pp.35-41
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• 2019

In this study, the fire resistance performance of polymer cement mortars which are used as a representative repair material for section restoration, is evaluated and residual bond strength is measured by considering unity with concrete. According to the evaluation of fire resistance performance of re-emulsification type polymer cement mortars, residual compressive strength was drastically decreased according to heating temperatures with an increase of polymer addition rate, and this seems to be attributable to the application of polymer film. In addition, an explosion phenomenon occurred frequently with an increase of addition rate, so this should be considered when selecting repair materials and processing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.125-126
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• 2023

This work explores the effectiveness of graphene nanoribbons (GNRs) in modifying the fire resistance of cement paste. The GNRs are added to the ordinary Portland cement at 0.10 wt% of the cement, and the sample is heated to target temperatures after curing for 28 days. Subsequently, the variations of compressive strength and pore structure are inquired by compared to the control sample without nano reinforcing and the sample with the same amount of carbon nanotubes (CNTs).

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.477-480
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• 2006

Normally, with all ensuring the fire resistance structure as a method of setting the required cover thickness to fire, the RC is significantly affected from the standpoint of its structural stability that the compressive strength and elastic modulus is reduced by fire. Especially, high strength concrete and lightweight aggregate concrete is occurred serious fire performance deterioration by explosive spalling. Thus, this study is concerned with explosive spalling of lightweight concrete using structural lightweight aggregate. From the experimental test result, lightweight aggregate concrete is happened explosive spalling. The decrease of cross section caused by explosive spalling made sharp increasing gradient of inner temperature.

• Steel and Composite Structures
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• v.9 no.3
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• pp.191-208
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• 2009

Observations from experiments and real fire indicate that restrained steel beams have better fire-resistant capability than isolated beams. Due to the effects of restraints, a steel beam in fire condition can undergo very large deflections and the run away damage may be avoided. However disgusting damages may occur in the beam-to-column connections, which is considered to be mainly caused by the enormous axial tensile forces in steel beams resulted from temperature decreasing after fire dies out. Over the past ten years, the behaviour of restrained steel beams subjected to fire during heating has been experimentally and theoretically investigated in detail, and some simplified analytical approaches have been proposed. While the performance of restrained steel beams during cooling has not been so deeply studied. For the safety evaluation and repair of steel structures against fire, more detailed investigation on the behaviour of restrained steel beams subjected to fire during cooling is necessary. When the temperature decreases, the elastic modulus and yield strength of steel recover, and the contraction force in restrained steel beams will be produced. In this paper, an incremental method is proposed for analyzing the behaviour of restrained steel beams subjected to cooling. In each temperature decrement, the development of deformation and internal forces of a restrained beam is divided into four steps, in order to consider the effect of the recovery of the elastic modulus and strength of steel and the contraction force generated by temperature decrease in the beam respectively. At last, the proposed approach is validated by FE method.

• Fire Science and Engineering
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• v.25 no.6
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• pp.64-72
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• 2011

The concrete void slab structure with the existing mushroom slab, is the structure that maximizes the advantages, while minimizing the weakness with removing useless body force of the concrete part, located on the center of the slab cross-section, which does not need to support the structural weight. In this research, a fire test is performed to analyze how the blaze behave according to the thickness of slab cover, with the practical span length of concrete void slab for the slab length 7.5 m. With this heating test, we assumed the uniform-load-model considering fixed loads and live loads, and chose the standard fire test condition. We measured the temperature changes and the deflection character according to the depth from the heat exposure side, and assessed the resisting capability according to the standard KS F 2257-1. The result comes out with the EPS model can secure about 2 hour fire-resisting-capability with 50 mm of cover depth.

• Journal of the Korea Institute of Building Construction
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• v.23 no.1
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• pp.23-33
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• 2023

It is widely known that the level of fire resistance of wooden structure is determined by a charring rate or charring depth, and these are adopted for fire design. In this study, specimens of domestic larch column with a lamination wooden type were prepared and the fire resistance properties such as the charring depth, load ratio and the specific charring rate suggested by EN Code investigated. Test results showed that as expected, the weakest part was the corner of the column, so that the charring depth of the corner was deeper than the other parts of the column. For the load ratio less than 0.9, it had little effect on the charring depth.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.469-472
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• 2005

With all ensuring the fire resistance structure as a method of setting the required cover thickness to fire, the RC is significantly affected from the standpoint of its structural stability that the compressive strength and elastic modulus is reduced by fire. Normally, the degradation of concrete member exposed to fire is largely dependent on the fire scale and fire condition. There is therefore a need to precisely predict the deterioration and fire damage of the exposed member. Thus, this work estimated the temperature distribution inside a member taking into consideration of the thermal properties by means of finite element method(FEM). The estimation results in a little higher prediction value than the experimental value in surface layer and is almost coincident with the experiment as the heating depth increase. From this work it can be known that the simulation application of FEM using the thermal properties of concrete member in high temperature gives rise to the confident prediction in the prediction of temperature distribution.

• Fire Science and Engineering
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• v.30 no.2
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• pp.35-42
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• 2016

The membrane structure provides high satisfaction with lightweight, improved workability, reduced cost, and a free shape. Thus, its applications expanding. On the other hand, in an architectural membrane that is vulnerable to fire, the development of various architectural membranes with flame resistance is in demand. Therefore, this study applied basalt woven fabric safety for flame resistance, excellent heat insulation and thermal properties on an architectural membrane. The PTFE- coated basalt woven fabric membrane was compared with a PTFE coated glass fiber membrane by DSC/TGA, strength properties, flammability, and incombustibility properties. In addition, this study confirmed the membrane applicability of basalt woven fabric and basalt-glass hybrid woven fabric through a comparison with existing architectural membranes.