Study On Calculation And Simulation Of High-speed Railway Capacity Under Different Speed Grade

After years of exploration and development,China's high-speed railway construction has made great achievements.From 2008 the first high-speed railway began to put into operation so far,China's high-speed rail mileage has reached the world's first,has occupied half of the world's high-speed rail.However,due to the special situation of China's national conditions and road conditions,China's high-speed railway in the next period of time will continue to use the " mixed operation of high and middle speed" mode of transport organization.With the "13th Five-Year" plan announced,China's high-speed railway network gradually rich,the traffic organization of different speed levels become more and more complex.Therefore,the study on the capacity of different speed levels is of great significance for the railway workers to organize more efficient high-speed railway operation.In this regard,this paper has done the following work:(1)This paper summarizes the advantages and disadvantages of each high-speed rail transport organization model which is mainly used in the countries of the world.The paper also makes an in-depth analysis of the " mixed operation of high and middle speed " organization model and the reasons for the adoption of the model.According to the situation of our country,this paper summarizes the characteristics of the capacity of high-speed railway in China,and summarizes the influencing factors of the capacity through two aspects: railway fixed equipment and transportation organization;This paper introduces several current methods of capacity calculation,and analyzes the limitations,advantages and disadvantages of each method.(2)According to the basic idea of the compressed train diagram proposed in UIC406,the calculation model of high speed railway capacity is established,and combined with the characteristics of the train diagram and the basic principle of Job-Shop problem,a genetic algorithm based on Job-Shop is designed.In this paper,make the high speed train as the A train,and the medium speed train as the B train.Through MATLAB simulation software,the changing trend of capacity under different speed matching scheme,mixed ratio and the number of track train are studied:(1)In the different speed matching scheme,the speed difference is the same,the faster the train speed,the greater the capacity;When the speed of B train is the same,the faster A train speed,the smaller the capacity.(2)In the different train mixing ratio,when the proportion of B train increases from 0 to100%,the capacity is reduced first and then increased.When the ratio of B train is about 50%,the capacity is the lowest.When the speed matching scheme is the same,with the increase ofthe proportion of B type train,the change range of capacity is closer;the greater the speed difference,the more serious the loss of capacity.(3)In the different number of trains tracking,when the number of B train which contained in the continuous tracking train group is 1,with the increase of A trains` number in each group,the capacity is increases;When the number of B trains increases continuously,the more number of A trains in each group,the grow speed of capacity is faster.The proportion of B trains in the continuous tracking train group is closer to the proportion of the overall B trains,the smaller the capacity.So,when the speed difference is the same,increasing the speed of all types of trains can improve the capacity.When the speed of B train is constant,the speed of A trains can be appropriately reduced,so as to achieve the effect of improving the passing capacity.When the train speed difference is large,the number of train B should not be too much;when the train speed difference is small,the number of B trains can be increased appropriately in order to fully meet the needs of different levels of passenger travel.