Research On Modeling And Simulation Of Rail Traffic Based On Cellular Automata

With shortening of the interval of the train following, some complex phenomenon of rail traffic flow have more and more impact on traffic safety and line capacity, such as the mutually influence of trains, train following operation and delay propagation of trains. Therefore, it’s significant to build the model which can describe complex phenomena of rail traffic flow to provide an effective simulation tool for studying the inherent law of phenomenon, analysis of forming mechanism and reducing the pernicious effects for improving the safety and efficiency of train operation.According to the principle of cellular automata, combining with characteristics of rail transportation the models of rail transit based on cellular automata are established and the traits of rail traffic flow are investigated. Firstly according to the different principle of signalling control system, cellular automata models of four-aspect of fixed block system, moving-like block system and moving block system are established respectively to simulate the actual train operating results well and to discuss the delay time effected by the departure time interval, the departure strategy, the proportion and the departure order of mixed train in different signalling control system. Secondly the cellular automata model at a station is proposed to demonstrate the train running behavior near the station accurately and to analyze the delay time effected by the number of lanes, the speed limit at a station and the stop time at a station. Thirdly the cellular automata model is proposed for the first time to simulate the rail traffic flow when a certain train will change lanes before arriving at a station or turn back from the rear of line and delays the following trains, then it researches the delay time effected by the speed limit when train is turning back and the throat length. Followed by the introduction of calculation about traction and braking force, a kind of cellular automaton model with variable acceleration is set up for the first time to reproduce some actual rail traffic flow successfully and makes an experience with a certain line to explore the traction distance and the rationality of line design. Finally, according to above models the simulation system of train track based on cellular automata is established to realize visual display of train running, and the numerical simulation result about the relationship between velocity, displacement and time is consistent with the actual situation. So they verify the availability and practicality of models and the simulation system.