基于CONE的超高温耐火电缆火灾危险性分析

Study on fire risk of ultra-high temperature fireresistant cable based on cone calorimeter test

利用锥形量热仪对超高温耐火电缆在不同辐射功率下的点燃时间(TTI)、热释放速率(HRR)、质量损失速率(MLR)和燃烧残余物进行了研究。研究表明,随着辐射功率增加,耐火电缆的TTI逐渐缩短,HRR和MLR逐渐增大,火灾危险性逐渐增加。超高温耐火电缆在35 kW/m^(2)和50 kW/m^(2)辐射功率下火灾性能指数相比于25 kW/m^(2)分别增加了44.4%和176.5%,火灾增长指数分别增加了30.4%和83.0%。结合理论分析可以得出,耐火电缆的临界辐射功率为3.61 kW/m^(2)、零辐射平均热释放速率为36.5 kW/m^(2),表现出较低的火灾危险性。

The ignition time,heat release rate,mass loss rate and combustion residue of ultra-high temperature fire-resistant cable under different external heat flux were analyzed via the cone calorimeter test.The results show that with the increase of external heat flux,the ignition time of cables is gradually shortened,the heat release rate and mass loss rate are gradually increased,so does the fire risk.The fire performance indexes of fire-resistant cables at the external heat flux of 35 and 50 kW/m^(2) increased by 44.4%and 176.5%,respectively,and the fire growth indexes increased by 30.4%and 83.0%,respectively,compared to those of 25 kW/m^(2).Combined with theoretical analysis,it can be concluded that the fire-resistant cable has the critical heat flux of 3.61 kW/m^(2) and average limiting heat release rate of 36.5 kW/m^(2),showing a low fire risk.