• Fire Science and Engineering
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• v.26 no.1
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• pp.80-88
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• 2012

This study evaluates the fire resisting capacity of the beam of the legal fire resistance construction, which establishes the Article 3 of the Regulations on Escape and Fire Resistance of Buildings. There are a total of five structures that we consider as legal fire resistance constructions, however, this study has a primary target of the reinforced concrete beam, and tests the fire-resistant performance depend on the covering depth of reinforce concrete. The results showed that it meets the three hours, the maximum statutory fire resistance time, if it was a load ratio of 0.5 and covering depth of 40 cm. Steel framed mortar beam is legal fire resistance structure that it was possessed three hours fire resistance performance, if it was a load ratio of 0.4 and covering depth of 60 mm.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4C
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• pp.283-290
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• 2006

Concrete has advantages in fire situations as it is non-combustible and has low thermal conductivity. However, concrete that is not designed against fire can experience significant explosive spalling from the build-up of pore pressures and internal tensile stresses when heated. In this study, the performance of wet-mixed high strength sprayed polymer mortar for fire resistance of tunnel system was evaluated by experimentally and numerically. The fire test was performed in fire resistance(electric) furnace according to RABT(Richtlinien fur die Ausstatung und den Betrieb von $Stra{\beta}entunneln$) time heating temperature curve, so as to evaluate the temperature distribution with cover thickness of wet-mixed high strength sprayed polymer mortar for fire resistance of tunnel system. Based on experimental results and numerical analysis, the proper cover thickness of wet-mixed high strength sprayed polymer mortar determined the more than 4cm.

• Fire Science and Engineering
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• v.24 no.4
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• pp.55-61
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• 2010

Fire resistance is very essential for all buildings to save peoples who live within buildings or use and to protect the properties when the buildings are covered with fire. The fire resistance were evaluated by loading or nonloading fire tests which are known very expensive and require lots of time. That causes the lacks of research activities and there are only small cases of fire resistance. The purposes of this paper are to analyze the temperature analysis for various structural elements such as columns and beams those are can be applied to buildings and to suggest the resonable fire protective thickness of concrete slab according to the required fire resistance time.

• Fire Science and Engineering
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• v.22 no.4
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• pp.85-94
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• 2008

The purpose of this study is to obtain the fundamental fire resistance performance of engineered cementitious composites (ECC) under fire temperature in order to use the fire protection material in high-strength concrete structures. The present study conducted the experiment to simulate fire temperature by employing of ECC and investigated experimentally the explosion and cracks in heated surface of these ECC. In the experimental studies, 5 HSC specimens are being exposed to fire, in order to exami ne the influence of vari ous parameters (such as depth of layer=20, 30, 40 mm; construction method=lining and repairing type) on the fire performance of HSC structures. Employed temperature curve were ISO 834 criterion (3 hr), which are severe in various criterion of fire temperature in building structures. The numerical regressive analysis and proposed equation to calculate ambient temperature distribution is carried out and verified against the experimental data. By the use of proposed equation, the HSC members subjected to fire loads were designed and discussed.

• Journal of the Korea Concrete Institute
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• v.18 no.4 s.94
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• pp.559-568
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• 2006

The purpose of this study is to evaluate the mechanical performance and fire resistance of wet-mixed high strength sprayed polymer-modified mortar in order to protect tunnel lining system which are in the event of fire disaster. Since the current commercial fire-resistant materials reproduce the low strength issue of mortar, this study aims to provide an enhanced fire-resistant mortar with a proper strength. Normally, a large temperature gradient phenomenon arise in the vicinity of free surfaces which are fully exposed in the event of persistent flame. Thereby, the determination of optimal cover depth of wet-mixed high strength sprayed polymer-mortar(WHSPM) is important for fire-resistance of tunnel lining system. With comparison of current commercial fire-resistance materials and WHSPM, the experimental result of WHSPM shows the better fire-resistant performance than the others. In addition, the cover limitation should be controlled by minimum 4cm depth in order to avoid fire-induced damage.

• Journal of the Korea Concrete Institute
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• v.22 no.2
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• pp.229-235
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• 2010

In this study, fire resistance performance of high strength concrete specimen with fireproof gypsum board was investigated for possible use in upgrading fire-resistant performance of the existing building and repair of fire damaged structures. Fire test of eight identical high strength concrete columns were carried out for 180 minutes in accordance with ISO-834. The temperature distributions in longitudinal reinforcement and concrete temperature at various depths were recorded. The fireproof performance of gypsum board and explosive spalling of concrete were observed. The specimens with 15 mm thick twoply fireproof gypsum board spalled after gypsum board crumbled regardless of fastening methods. However, when the thickness of fireproof gypsum board was more than 30 mm, it was possible to prevent the explosive spalling and control the rebar temperature. Although the effect of cover thickness could not be compared because the explosive spalling occurred, there seemed to be no difference in insulation efficiency.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.04a
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• pp.4-5
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• 2013

프리스트레스트된 프리캐스트 콘크리트 부재는 장경간이 가능하고 공장생산으로 품질관리가 용이하다. 그러나 프리스트레싱 텐던이 화재에 노출되는 경우 일반 철근에 비해 급격하게 강도를 상실해 구조물의 붕괴로 이어질 수 있다. 국내의 경우 실험에 기초한 내화성능에 대한 연구는 활발히 이루어지고 있으나 그에 반해 성능기반 설계법이 활성화 될 때 요구되는 수치해석적인 연구는 많이 부족한 실정이다. 따라서 본 연구에서는 문헌조사를 통해 이전에 수행된 실험 데이터를 통해 현재 외국에서 활발히 사용되는 수치해석 프로그램을 검증하고 수치해석 모델링을 통해 각각의 내화시간에 따른 적절한 피복 두께를 제안하였다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.17-20
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• 2010

기존의 무량판 구조와 동일한 이방향 슬래브구조인 TVS(two-way void slab)공법은 구조적 하중지지 성능이 불필요한 슬래브 단면상의 중앙부 콘크리트를 제거하여 슬래브의 자중을 줄이고 무량판 구조의 단점을 보완하여 장점을 극대화시킨 구조형식이다. 그러나 이러한 장점을 보유한 공법을 현장적용하기 위해서는 내화성능평가를 통해 화재안전성을 확보하여야 하므로, 이에 대한 화재 실증실험을 수행하여 현장적용을 위한 최소 요구내화 시간에 따른 내화성능 확보방안의 도출이 제시되어야 한다. 이에 본 연구에서는 TVS공법의 실제 스팬길이로 슬래브 피복두께에 따른 화재거동 영향성 분석을 위하여 화재실험을 수행하였다. 하중조건은 고정하중과 적재하중을 고려하여 실험체에 등분포 조건으로 사전재하하였으며, 표준화재조건으로 재하가열 실험을 수행하였다. 슬래브의 화재가열 노출면으로부터의 깊이별 온도변화와 처짐변형 특성을 측정하였으며, KS F 2257-1 평가기준에 의거하여 슬래브의 내화성능을 평가하였다. 실험결과 피복두께 50 mm를 확보할 경우, EPS중공체로 제작한 실험체의 경우 약 2시간정도의 내화성능을 확보할 수 있는 것으로 나타났다.

• Magazine of the Korea Concrete Institute
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• v.11 no.4
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• pp.25-31
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• 1999

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.181-188
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• 2011

Spalling must be considered when designing high-strength concrete to cope with fire. This study investigates the temperature rise of steel bar in high-strength concrete coated with fireproof mortar using gypsum exposed to fire. It was found that fireproof mortar using gypsum is more effective in constraining the temperature rise of steel bar in the high strength concrete than fireproof mortar using cement, and that the thinner the cover depth of the fireproof mortar, the more significant the influence of the gypsum. In addition, while there was no difference between ${\alpha}$-hemihydrate mortar and ${\beta}$-hemihydrate mortar on the temperature rise of steel bar, the compressive strength of ${\alpha}$-hemihydrate mortar is higher than that of ${\beta}$-hemihydrate mortar.