Fire resistance assessment in construction joint of precast fireproof duct slab

Soon-Wook Choi; Tae-Ho Kang; Chulho Lee; Se Kwon Kim; Tae Kyun Kim; Soo-Ho Chang

doi:10.9711/KTAJ.2021.23.5.359

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2021 Vol.23, Issue 5 Preview Page

Technical Paper

Fire resistance assessment in construction joint of precast fireproof duct slab 프리캐스트 방식 내화풍도슬래브 시공조인트부의 화재저항성능 평가

30 September 2021. pp. 359-370

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Abstract

Duct slabs, which are used to build ventilation facilities in underground spaces with transverse ventilation system, need to secure fire resistance according to longitudinal and heavy vehicle traffic of tunnels. This study measured the temperature change at the construction joint of the precast fireproof duct slab which integrates fire resistance material and duct slab under the RWS fire scenario. As a result, it was confirmed that if there is no reinforcement of the construction joint, damage will occur in concrete inside the construction joint, leading to damage to the fireproofing layer. On the other hand, when one side of the construction joint was reinforced with fireproofing materials, it showed more than three times the fire resistance performance compared to when there was no reinforcement. At this time, cross-sectional losses of concrete and fireproofing layer were shown in blocks without reinforcement, but no damage was seen in the reinforced blocks.

Keywords

Tunnel

Fire

Duct slab

Construction joint

Temperature

횡류식으로 지하공간의 환기시설을 구축할 때 사용되는 풍도슬래브는 터널의 장대화 및 중차량 통행에 따라 내화성능 확보가 필요하다. 본 연구는 내화재와 슬래브를 일체식으로 제작하는 프리캐스트 내화풍도슬래브를 대상으로, RWS화재시나리오 하에서 내화풍도슬래브를 시공할 때 발생하는 시공조인트부에서의 온도변화를 측정하였다. 그 결과, 시공조인트부의 보강이 없을 경우는 시공조인트부 안쪽의 콘크리트에서 손상이 발생하여 내화재의 손상으로 이어짐을 확인하였다. 반면 시공조인트 내측의 한쪽 면을 내화재로 보강한 경우는 보강이 없을 경우에 비해 3배 이상의 화재저항성능을 보였지만, 보강이 없는 블록에서 콘크리트 및 내화재의 단면손실이 나타났다. 그러나 보강된 블록에서는 손상이 나타나지 않았다.

키워드

터널

화재

풍도슬래브

시공조인트

온도

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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 : 23
No :5
Pages :359-370
Received Date : 2021-08-24
Revised Date : 2021-09-10
Accepted Date : 2021-09-13
DOI :https://doi.org/10.9711/KTAJ.2021.23.5.359

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

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