• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.46-49
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• 2012

지하대공간은 특수한 가연물 및 높은 밀도의 화재하중을 지닌 가연물이 많으나, 국내 내화성능기준은 이를 고려하지 않고 있다. 이에 본 연구는 슬래브실험체를 제작하여 표준가열곡선(ISO834)과 지하대공간의 화재하중을 고려한 화재조건으로 내화실험과 수치해석을 실시하였으며, 그 결과 모든 실험체에서 0.96~1.03로 10%내의 오차범위에 있는 것을 확인 할 수 있었다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.3
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• pp.289-300
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• 2013

This study numerically considered the characteristic of smoke movement and the effect of hot smoke gas on tunnel wall surface temperature during road tunnel fire under boundary condition of fire growth curve that is applied to fire analysis in road tunnels. The maximum heat release rate were 20 MW and 100 MW and tunnel air velocities were 2.5 m/s and velocity induced by thermal buoyancy respectively, also the cooling effect of tunnel wall was considered. As results, when tunnel air velocity was constant at 2.5 m/s during tunnel fire, due to the cooling effect of tunnel wall, the smoke layer was rapidly descent after some distance and it flowed the same patterns at the downstream. When heat release rate was 100 MW (and jet fan was not installed), the maximum temperature of tunnel wall surface has risen up to $615^{\circ}C$. The heat transfer coefficient of tunnel wall surface was varied from 13 to $23W/m^2^{\circ}C$ approximately.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.497-508
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• 2013

This paper introduces a numerical model which can evaluate the fire-resistant capacity of reinforced concrete members. On the basis of the transient heat transfer considering the heat conduction, convection and radiation, time-dependent temperature distribution across a section is determined. A layered fiber section method is adopted to consider non-linear material properties depending on the temperature and varying with the position of a fiber. Furthermore, effects of non-mechanical strains of each fiber like thermal expansion, transient strain and creep strain are reflected on the non-linear structural analysis to take into account the extreme temperature variation induced by the fire. Analysis results by the numerical model are compared with experimental data from the standard fire tests to validate an exactness of the introduced numerical model. Also, time-dependent changes in the resisting capacities of reinforced concrete members exposed to fire are investigated through the analyses and, the resisting capacities evaluated are compared with those determined by the design code.

• Journal of Energy Engineering
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• v.29 no.3
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• pp.97-102
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• 2020

In this study, one-way fluid structure interaction analysis was adapted to verify the durability of the outdoor evacuation stair structure operated in the event of a fire when wind pressure caused by a typhoon was applied. To this end, flow analysis was performed with the flow field around the structure of the evacuation stair in a steady state, and the durability was analyzed through structural analysis such as structural stress, deformation, and fatigue life using these analysis results by fluid data input data for structural analysis. As a result of flow numerical analysis, the air flow was different according to the shape of the evacuation stair structure, and this flow velocity distribution generated by the total pressure on the structure surface. Through the structural analysis results calculated by this total pressure, the safety factor calculated as the maximum stress value was found to be more than the safety factor, and durability was proven by fatigue life and deformation analysis.

• Fire Science and Engineering
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• v.29 no.5
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• pp.23-28
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• 2015

Recently, structural materials have been developed to have high performance, and SM 520 has been developed and used for high-rise buildings. However, fires frequently occur in buildings, and the number of victims and amount of damage increase year by year. However, the evaluation of fire resistance performance for structural beams made of SM 520 is done with specimens made of ordinary structural steels with boundary conditions of a fixed beam, and the results are allowed for use in steel-framed buildings. This study analyzed the fire resistance performance of statistically indeterminate beams built with SM 520. The analysis used a fire engineering technique that includes mechanical and thermal data of SM 520 and heat transfer theory, and heat stress analysis was also conducted. The results from the analysis were compared with those from a statistically determinate beam made of ordinary structural steels.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.540-547
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• 2009

국내도로터널 화재안전성을 확보하기 위하여 FDS를 이용하여 ISO, 도로터널 방재시설기준, Runner Hammer 터널기준의 시나리오에 따라 콘크리트 터널구조물의 내부 열역학적 특성을 예측하였다. 화재로 인한 터널내부의 온도분포를 측정하기 위하여 화염원으로부터 터널입구 방향으로 5m 마다 터널 단면의 온도분포를 추출하였고, 터널의 중심을 지나는 길이방향 단면의 온도분포를 해석하였다. 해석결과 온도는 500${\sim}$950$^{\circ}C$까지의 분포를 나타내었고 가장 높은 온도영향을 받은 Runner Hammer 터널기준의 내부 열환경 조건에서는 터널 단면이 모두 화염에 직접적으로 노출 때문에 단면전체가 800${\sim}$950$^{\circ}C$까지 상승하였다. 특히 상부부분은 900$^{\circ}C$ 이상의 고온에 장시간 노출되고 있어 깊이 50mm 지점의 온도가 250$^{\circ}C$까지 상승하였다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.172-173
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• 2013

발코니 확장에 따른 아파트의 화재안전기준 강화를 목적으로 건축법 시행령 제 46조 제 4항의 규정에 따라 현재 건축되고 아파트에는 $2m^2$이상의 대피공간을 설치해야 한다. 그리고 대피공간은 채광방향과 관계없이 거실 각 부분에서 접근이 용이한 장소에 설치해야 하며, 출입구에 설치되는 갑종방화문은 거실쪽에서만 열 수 있는 구조로 해야한다. 하지만 현재 시공되고 있는 방화문은 비차열성 방화문으로써 거실공간에서 화재가 발생하였을 경우 방화문의 열전달 현상에 의해 대피공간 내부의 온도상승이 유발되지만 현재 방화문의 차열성능에 대한 규정이 부재하기 때문에 향후 인명피해가 우려되는 상황이다. 본 연구에서는 실제 방화문의 성능시험을 통해 대피공간과 접한 방화문 면의 온도변화를 측정하였으며, 이로 인한 대피공간 내부의 온도변화를 분석하기 위해 수치해석을 수행하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.284-289
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• 2019

The Korea Foldable safe pathway system is an evacuation support system to get temporary evacuation route in railway tunnel and large space fires. A prevention smoke screen is unfolded in fires and it is needed to prevent heat and smoke from fire source. Therefore, ventilation system for positive pressure condition is equipped with foldable safe pathway system. Numerical analyses of temperature and pressure distribution with distance from fire source were performed considering fire scenario of new train vehicle. The smoke temperatures did not exceed $200^{\circ}C$ that distance from the fire source was more than 20 m and smoke pressure was reduced with distance from fire source. Maximum smoke pressure was 14 Pa and average pressure was 6 Pa in position of prevention smoke screen. As results, to install foldable safe pathway system, ventilation system is need to maintain 6 Pa positive pressure condition.

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.655-664
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• 2006

The purpose of thisanalytical study of an iTECH composite beam subjected to fire conditions is to determine the beam's fire resistance performance using its load ratio and fire protection as parameters. A composite structural system is expected to have a safer and more economical fire safety design than a mere collection of isolated members.heat transfer analysis was performed on the basis of the finite element program ANSYS 10.0 using an ISO834 standard fire, following the main guidelines proposed by EC1 Part 2.2 and EC4 Part 1.2. To validate the analytical simulation of the iTECH composite beam, comparison of the experimental tests was proposed.

• Journal of the Korea Concrete Institute
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• v.29 no.3
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• pp.237-248
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• 2017

Frequent terror or military attack by explosion, impact, fire accidents have occurred recently. These attacks and incidents raised public concerns and anxiety of potential terrorist attacks on important infrastructures. However, structural behavioral researches on prestressed concrete (PSC) infrastructures such as Prestressed Concrete Containment Vessel (PCCV) and Liquefied Natural Gas (LNG) storage tanks under extreme loading are significantly lacking at this time. Also, researches on possible secondary fire scenarios after terror and bomb explosion has not been performed yet. Therefore, a study on PSC structural behavior from an blast-induced fire scenario was undertaken. To evaluate the blast-fire combined resistance capacity and its protective performance of bi-directional unbonded PSC member, blast-fire tests were carried out on $1,400mm{\times}1,000mm{\times}300mm$ PSC specimens. Blast loading tests were performed by the detonation of 25 kg ANFO explosive charge at 1.0 m standoff distance. Also, fire and blast-fire combined loading were tested using RABT fire loading curve. The test results are discussed in detail in the paper. The results can be used as basic research references for related research areas, which include protective design simulation under blast-fire combined loading.