气膜钢筋混凝土结构粮仓火蔓延特性研究

Study on fire propagation characteristics of gas film reinforced concrete structure grain silo

气膜钢筋混凝土结构圆顶粮食仓(以下简称“气膜粮仓”)因具有安全性高、气密性强、隔热性好以及节能环保等优点而在我国得到了应用。然而,有关气膜粮仓的消防安全可靠性研究尚无定论。因此,本研究通过构建模拟火灾场景,分析了气膜粮仓发生火灾的可能性及原因,研究了粮仓外壁火蔓延特性。试验结果表明,气膜粮仓外层PVDF层和聚氨酯保温层能够被火源引燃并发生蔓延。距墙体2.5 m处最大热通量小于1.0 kW/m^(2),未达到点燃普通可燃物的热通量。此外,距墙体2.5 m处的温度未超过100℃,未达到柔性聚氨酯泡沫270℃的点燃温度。考虑一定的安全余量,建议防火间距应不小于3.0m。同时本文还提出了适合气膜粮仓的消防保护措施。

The gas film reinforced concrete structure dome grain silo(hereinafter referred to as"gas film grain silo")has been ap-plied in China due to its advantages of high safety,strong airtight-ness,good thermal insulation,and energy conservation and envi-ronmental protection.However,there is no consensus on the fire safety and reliability research of gas film granaries.Therefore,this study constructed a simulated fire scenario to analyze the pos-sibility and causes of fire in an gas film grain silo,and studied the characteristics of fire spread on the outer wall of the silo.The ex-perimental results indicate that the outer PVDF layer and polyure-thane insulation layer of the gas film granary can be ignited and spread by a fire source.The maximum heat flux at a distance of 2.5 meters from the wall is less than 1.0 kW/m^(2),which does not reach the heat flux required to ignite ordinary combustibles.In ad-dition,the temperature 2.5 m away from the wall does not exceed 100℃,and does not reach the ignition temperature of 270℃ for flexible polyurethane foam.Considering a certain safety margin,it is recommended that the fire separation distance should not be less than 3.0 meters.At the same time,this article also proposes fire protection measures suitable for gas film granaries.