The critical location for thermal radiation disaster in personnel evacuation of rack railway tunnel fires under the large longitudinal slope

Abstract

Thermal radiation has a great effect on personnel evacuation when the train is on fire in the rack railway tunnels. However, the influence of the longitudinal slope, especially the large longitudinal slope, is not clear. The critical location of a disaster caused by thermal radiation is proposed. Based on the FDS, the correction models of maximum temperature rise and longitudinal temperature decay of rack railway tunnel with slope are obtained for random evacuation mode and fixed-point evacuation mode. And the theoretical model for the critical location is established. The results show that the maximum temperature rise and the longitudinal temperature attenuation are related to the cubic and quadratic equations of the longitudinal slope, respectively. A decreasing effect is observed in the maximum temperature rise of the rail railway tunnel with a large longitudinal slope, and the degree of longitudinal attenuation is extremely small. In this case, the thermal radiation under the random evacuation mode is less risky than that under fixed-point evacuation mode, which is more conducive to evacuation. The accuracy of the theoretical model is high, and the maximum error is 21.4%. The results can support emergency works, such as rescue engineering design and personnel evacuation induction.