Fire resistance assessment of high strength segment concrete depending on PET fiber amount under fire curves

Soon-Wook Choi; Gyu-Phil Lee; Soo-Ho Chang; Young-Taek Park; Gyu-Jin Bae

doi:10.9711/KTAJ.2014.16.3.311

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2014 Vol.16, Issue 3 Preview Page Next Page

Fire resistance assessment of high strength segment concrete depending on PET fiber amount under fire curves 화재곡선과 PET섬유 혼입량에 따른 고강도 세그먼트 콘크리트의 화재저항성 평가에 대한 연구

31 May 2014. pp. 311-320

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Abstract

High strength concrete is not only vulnerable to the occurrence of spalling which generates the loss of cross-section in concrete structures but produces faster degradation in its mechanical properties than normal strength concrete in the event of fire. This study aims to evaluate fire resistance of high strength segment concrete with PET fibers mixed to prevent spalling under ISO834 (2hr) and RABT fire curve. As results, the samples without PET fibers show the concrete loss up to the depth of about 8 cm and 9.5 cm from the surface exposed to fire under ISO834 and RABT fire curve respectively. The samples mixed with PET fiber of 0.1% show no spalling under ISO834 fire curve and the spalled thickness of 6.5 cm under RABT fire curve after the fire tests. Finally, the sample mixed with PET fiber of 0.2% shows no spalling under RABT fire curve. The results indicate that the suitable amounts of PET fiber for securing fire resistance performance of this high strength segment concrete are 0.1% under ISO834 fire curve and 0.2% under RABT fire curve. However, even though spalling does not occur, it is necessary to repair the deterioration of concrete up to 4 cm from the surface exposed to fire after fire.

Keywords

Fire resistance

Segment lining

PET fiber

ISO834 fire curve

RABT fire curve

화재 시 고강도 콘크리트는 보통강도 콘크리트보다 강도의 감소가 빠르게 나타날 뿐만 아니라 단면손실을 발생시키는 스폴링(spalling)에 취약하다. 본 연구에서는 PET섬유가 혼입된 고강도 세그먼트 콘크리트를 대상으로 ISO834 화재곡선과 RABT 화재곡선 하에서 화재저항성을 평가하였다. 화재저항성을 시험한 결과, PET섬유가 혼입되지 않았을 경우에 ISO834 화재곡선과 RABT 화재곡선 하에서 콘크리트의 단면손실은 약 8 cm, 9.5 cm로 측정되었다. ISO834 화재곡선 하에서 PET섬유가 0.1% 혼입되었을 경우에는 단면손실이 발생하지 않았으나, RABT 화재곡선 하에서는 PET섬유가 0.1% 혼입되었을 경우에는 6.5 cm의 단면손실이 발생하였다. RABT 화재곡선 하에서는 PET섬유가 0.2% 혼입되었을 경우에 단면손실이 발생하지 않았다. 따라서 본 연구에서 사용한 세그먼트 콘크리트는 PET섬유의 혼입량이 0.1%일 때 ISO834 화재곡선 하에서 내화성능을 확보하였으며 RABT 화재곡선 하에서는 PET섬유의 혼입량이 0.2%일 때 내화성능을 가지는 것으로 나타났다. 그러나 단면손실이 발생하지 않았더라도 가열면으로부터 4 cm까지의 손상된 표면의 보수보강이 필요한 것으로 판단된다.

키워드

화재저항성

세그먼트라이닝

PET섬유

ISO834 화재곡선

RABT 화재곡선

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Information

Publisher :Korean Tunneling and Underground Space Association
Publisher(Ko) :한국터널지하공간학회
Journal Title :Journal of Korean Tunnelling and Underground Space Association
Journal Title(Ko) :한국터널지하공간학회 논문집
Volume : 16
No :3
Pages :311-320
Received Date : 2014-05-07
Revised Date : 2014-05-19
Accepted Date : 2014-05-21
DOI :https://doi.org/10.9711/KTAJ.2014.16.3.311

Journal of Korean Tunnelling and Underground Space Association ISSN:2233-8292(Print) 2287-4747(Online) 한국터널지하공간학회 논문집

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