A Study on the Heat Hazard Assessment of Building Wood

Abstract

본 연구는 건축용 목재의 화재위험성에대하여 열방출 특성을 중심으로 조사하였다. 열방출 성질은 cone calorimeter (ISO 5660-1)를 이용하여 측정하였으며 4종의 목재를 사용하였다. 외부 열유속 25 kW/m에서 연소시킨 후 측정된 착화시간은 35s부터 55s까지였다. 나왕(lauan)과 적송의 착화 시간은 각각 54s, 55s로 가장 지연된 값으로 얻어졌다. 최대열방출율은 156.87~235.1 kW/m2였고 화재초기의 위험성은 가문비나무가 가장 높았다. 삼나무의 평균유효연소열은 19.1 MJ/kg였고 시료들 중에서 가장 높게 나타났다. 화재성능지수(FPI)에 의한 목재의 화재위험성은 나왕(0.2468 s·m²/kW) < 적송(0.2339 s·m²/kW) < 가문비나무(0.2308 s·m²/kW) < 삼나무(0.2231 s·m²/kW) 순으로 높았고 화재성장지수(FGI)에 의한 목재의 화재위험성은 나왕(0.5088 kW/m²·s) < 적송(0.511 kW/m²·s) < 삼나무 (2.8522kW/m²·s) < 가문비나무(3.0662 kW/m²·s) 순으로 높았다. 그러므로 목재의 열방출 특성에 대한 화재위험성은 가문비나무와 삼나무가 높은 것으로 나타났다.This study was carried out with respect to the heat release rate (HRR) properties of building wood. Heat release characteristics were measured using a cone calorimeter (ISO 5660-1) with four kinds of wood. The time to ignition measured after the combustion in 25 kW/m² external heat flux was 35 to 55 s. Time to ignition of both lauan and red pine was marked with the most delayed value in each of 54 s, 55 s. The maximum heat release rate (HRR peak) was 156.87~235.1 kW/m², and the risk of early fire was highest in spruce. Total heat release of red pine was obtained in the highest value with 114.2 MJ/m². The mean effective heat of combustion of Japanese cedar was 19.1 MJ/kg and the highest among the samples. Fire risk of wood by FPI was orderly increased from lauan (0.2468 s·m²/kW), red pine (0.2339s·m²/kW), spruce (0.2308s·m²/kW) to Japanese cedar (0.2231 s·m²/kW). Fire risk of wood by FGI get increased from lauan (0.5088 kW/m²·s), red pine (0.5111 kW/m²·s), Japanese cedar (2.8522 kW/m²·s) to spruce (3.0662 kW/m²·s). Therefore, the risk of fire on the heat release characteristics of woods were found that spruce and Japanese cedar showed the high value compared with the other specimens.