Study On Evacuation Of Train Fires In High-speed Railway Long Tunnel

High-speed railway has brought humanity efficiency and convenience. At the same time, the railway traffic accidents have caused tremendous economic losses and social impact. As key nodes in the high-speed railway, the traffic safety of the tunnel has been the focus of the railway operational management. With the continuous increase of traffic speed and the growing number of long tunnels, the possibility of train fires inside tunnels will also increase, and the evacuation will be very difficult. How to reduce the possibility of train fires and to ensure the evacuation has become an urgent issue to resolve.Through comprehensive analysis of case studies, theoretical study and numerical simulation, this paper makes a systemic discussion on the evacuation models of train fires in high-speed railway tunnel. It focuses on the following aspects:(1)Train fires in railway tunnels home and abroad are investigated to obtain the main causes of train fire. The fire location and the consequence of the accidents are also analyzed.(2)The evacuation models of train fires ("continue-to-operate" evacuation model and "parking" evacuation model) are discussed to obtain the most adverse scenes. The safety criterion of two evacuation models are also established(3) The theoretical basis for tunnel fire three-dimensional numerical simulation is analyzed. The suitable tunnel fire model is selected and the "wind piston equivalent method" is suggested to simulate the "continue-to-operate" evacuation model..(4)To study the "continue-to-operate" evacuation model, the influencing factors on smoke flow fluid such as the heat release rate, train speed, tunnel section are discussed. Case study is done to obtain the criterion of using this model. Also the evacuation direction under different locations in tunnel is analyzed. The worst location Lcr to evacuate is found to make the evacuation time longest. In the end, the reasonable evacuation speed is discussed.(5)To study the "parking" evacuation model, the critical velocity of the Shiziyang railway tunnel is calculated by empirical formula and numerical simulation. The reasonable distance of the cross passage is also discussed.(6)An investigation on the specifications home and abroad is made. Based on the study results; the suggestions on the disaster prevention of the high-speed railway long tunnels are given.