高层住宅楼外墙保温系统火灾蔓延的数值模拟

Numerical Simulation of External Wall Insulation System Fire in High-rise Residential Building

为研究施工中高层建筑外墙保温材料火灾蔓延规律及温度场分布情况,利用火灾动力学模拟软件FDS(Fire Dynamics Simulator),建立了一栋20层钢筋混凝土住宅楼实体的数值分析模型,模型中包括施工脚手架和尼龙安全网,火源点位于第6层的外墙上。分析得到了火灾的发生及蔓延、温度场分布、CO浓度分布规律。研究结果表明,火灾开始时,火焰先沿水平方向发展,然后向上蔓延,并迅速蔓延至整个外表面,即呈表皮着火现象;窗户玻璃爆裂后,室内可燃物被点燃,形成立体燃烧;在建筑凹槽处,产生烟囱效应,燃烧最为剧烈,温度高达1000℃;在整个火灾蔓延过程中,温度出现2个峰值点。研究成果可为高层建筑室外火灾采取防控措施提供参考。

In order to investigate the fire spread and temperature field of external wall insulation material in high-rise building, the numerical simulation model of a 20-story reinforced concrete residential building was made by Fire Dynamic Simulator （FDS）. Bamboo scaffold and nylon safety net were included in the model. The fire originated on the outside wall of the second floor. The laws of fire spreading, temperature field and carbon monoxide distributions were obtained. The results show that the fire spread in horizontal direction then in vertical direction. In a short time, fire spreads the whole surface, namely skin burning phenomena. After window glasses breaking, the combustibles of compartment were ignited and three-dimensional combustion was occurred. Chimney effect rises in the slots of the building, the highest temperature at 1000℃ ap- peared in these slots. There are two peak temperatures in the whole fire process. The results are valuable for fire precaution measures of outdoor fire in high-rise building with external wall insulation.