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One-Dimensional Heat Transfer Model to Predict Temperature Distribution in Voided slabs subjected to fire

화재 시 중공슬래브의 온도분포 예측을 위한 1방향 열전달 모델

  • 정주홍 (삼육대학교 건축학과) ;
  • 최현기 (경남대학교 소방방재공학과)
  • Received : 2019.05.30
  • Accepted : 2019.08.20
  • Published : 2019.09.01

Abstract

In general, a reinforced concrete slabs are known to have a high fire resistance performance due to thermal properties of concrete materials. However, according to previous research, the thermal behavior of voided slabs is reported to be different from that of conventional RC solid slabs, and the differences seem to be caused by the air layer formed inside the voided slab. Therefore, it is difficult to estimate the temperature distribution of the voided slab under fire by using the existing methods that do not take into account the air layer inside the voided slab. In this study, a numerical analysis model was proposed to estimate the temperature distribution of voided slabs under fire, and evaluated. Heat transfer of slabs under fire is generally caused by conduction, convection and radiation, and time-dependent temperature changes of slab can be determined considering these phenomena. This study proposed a numerical method to estimate the temperature distribution of voided slabs under fire based on a finite difference method in which a cross-section of the slab is divided into a number of layers. This method is also developed to allow consideration of heat transfer through convection and radiation in air layer inside of slabs. In addition, the proposed model was also validated by comparison with the experimental results, and the results showed that the proposed model appropriately predicts the temperature distribution of voided slabs under fire.

Keywords

Voided slabs;heat transfer;thermal distribution;finite difference method

Acknowledgement

Supported by : 한국연구재단

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