Specialty Rail Tunnel Fire In The Characteristics And Dangers Of Research

With the increasing number of tunnels, especially the emerging extra-long tunnels, the probability of fire accidents happening in tunnels has risen as well. Once trains catch fire in the high-speed railway tunnel, the evacuation and rescue would be very difficult, among which will also result in very negative social impacts. Therefore, the study on features of fire smoke spread and harmfulness of the railway tunnel is of great significance. In this thesis, the process of fire smoke spread in the tunnel and evacuation issues of train safe running are mainly numerical simulation, combining theoretical analysis and experimental data to establishe the formula of key parameters of fire safety design.The main findings and conclusions can be listed as follows:According to the energy conservation theory, the theoretical model of slope influcing on tunnel fire is established; combining numerical simulation and analysis of model test data, the mechanism of slope affecting the fire of railway tunnel is given.The law of tunnel smoke spread is studied through numerical simulation and model experimentation, combining with theoretical analysis to establish a formula between backflow distance of smoke in the tunnel and slope of the tunnel, fire intensity, tunnel section and other related parameters.Theoretical analysis is conducted on the Critical ventilation velocity controling smoke backflow in the tunnel; theoretical formula of Critical ventilation velocity is derived and its unknown factor is determined through model experimental data. The derived formula of Critical ventilation velocity is simple and easy to determine the unknown parameters which help predict Critical ventilation velocity and can be promoted.The validity of Kurioka maximum temperature model is analyzed under different fire situations; its applicable scope is got, the model is revised and a wide application prediction model of maximum temperature near the tunnel vault is given.The problems of safety evacuation about the train catching fire to run at different speeds and conditions of vehicles and people in vehicles to reach dangerous situation are discussed. The maximum time of safe evacuation and distance of safe evacuation are proposed under train running on fire. Those open up a new way and provide theoretical support for evacuation of train fire accidents in future.Compared to highway tunnels and subway tunnels, railway tunnel fire safety research is still not perfect, disaster prevention and rescue regulations also relatively rough. Therefore, the research results of the thesis will provide valuable reference for the design of the railway tunnel disaster prevention and establishment of evacuation pan...