As the golden period for evacuation and rescue in road tunnel fires, the fire growth stage is indispensable for security. The key parameters of this stage must be clearly defined, including the maximum heat release rate (HRR), growth time, and growth coefficient. Based on the squared model, the correlations between the key parameters are investigated according to the existing fire tests of vehicle-related materials and actual vehicles or mock-ups. The maximum HRR and the growth coefficient of different types of vehicles are obtained. The results show that the maximum HRR is linearly related to the growth coefficient in the fire tests of vehicle-related materials. And it is logarithmically related in the fire tests of actual vehicles or mock-ups. The growth coefficient and growth time represent the possibility of a disaster. The larger the growth coefficient is or the shorter the growth time is, the greater the possibility is. The maximum HRR in a fire is 2 ~ 10 MW for a car, 10 ~ 50 MW for a bus, and 50 ~ 200 MW for a heavy goods vehicle. The growth coefficient in a fire is 0.003 ~ 0.013 kW/s² for a car, 0.05 ~ 0.15 kW/s² for a bus, and 0.2 ~ 0.3 kW/s² for a heavy goods vehicle. The corresponding fire growth types are slow and medium, fast, fast, and ultra-fast, respectively. This study is beneficial for the establishment of the fire growth model and the setting of emergency response time.

中文翻译：

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公路隧道车辆火灾发展阶段关键参数研究

作为公路隧道火灾疏散救援的黄金期，火灾发展阶段对于安全来说是不可或缺的。该阶段的关键参数必须明确定义，包括最大放热率（HRR）、生长时间和生长系数。基于平方模型，根据现有的车辆相关材料与实际车辆或模型的防火测试，研究关键参数之间的相关性。得到了不同类型车辆的最大HRR和增长系数。结果表明，在车辆相关材料的防火试验中，最大HRR与增长系数呈线性相关。在实际车辆或模型的火灾测试中，它呈对数关系。成长系数和成长时间代表灾难发生的可能性。增长系数越大或增长时间越短，可能性就越大。火灾中的最大HRR为汽车2～10MW，公共汽车10～50MW，重型货车50～200MW。火灾中的增长系数，汽车为0.003～0.013kW/s ² ，公共汽车为0.05～0.15kW/s ² ，重型货车为0.2～0.3kW/s ^{2 。}相应的火势增长类型分别为慢速和中速、快速、快速和超快速。本研究有利于火灾发展模型的建立和应急响应时间的设定。