Calculation Method Of The Throat Capacity Of Railway Passenger Hub Station Based On The Stochastic Model

Throat capacity is the limit carrying capacity of the station, correct analysis and evaluation on the throat capacity of railway station play an important role in taking full advantage of infrastructure, optimizing transport organization work and improving transportation capability and efficient of railway network. At present, the relatively mature computing method of station capacity in our country is utilization rate calculation method. As a static method, it has unfitness in calculation, for instance, train delays, time variation of route operation and other random factors are not considered, which leads to the imprecision of the computation.Based on the static method of utilization and probability theory, this paper analyzes the impacts on pass capacity of throat area by train delays and time variation of route operation under the situation of different randomness, also, this paper provide an optimized model of random probability on the basis of the theory and characters of train delays and time variation of route operation; train delays, unfixable working hour and other factors was described by random model and corresponding probability distribution is made by empirical data in this paper. As for algorithm, this paper, combining the probabilistic optimization model, developed the automatic calculation system of station throat’s passing capacity, using computer to realizethe capability calculation of the basic utilization rate method of the Erlang distribution and random model of the normal distribution method. According to calculation result, Analysis the effects of the random fluctuations within a certain range of the station’s throat area, and give optimization Suggestions to line using and throat expansion. In this paper, the main working procedures and contents we studied are as follows:(l)Set forth the research background and significance of this paper, introduce some research results of capacity calculation method of railway station over the world;(2)To analyze the characteristics of the railway passenger transport hub throat operation and key points for capacity calculation, the advantages and disadvantages of utilization rate of depth profiling method. Introduce the probability of random thoughts and optimized the unreasonable place in the practical application.(3)Taking the station throat as the main research object, via analyzing the influence factors of the ability of the station throat, considers train secondary later, and the operation time fluctuations and other random factors,random probability optimization model is established(4)According to the stochastic optimization model in the third chapter, develops the station throat passing capacity automatic calculation system, and gives the use rate method and random probability method; Meanwhile, embeds the random probability algorithm into computing system, and makes out the stochastic model based on the ability of the automatic calculation system of the throat.(5)Taking Beijing south railway station as examples for analysis, calculates two kinds of stochastic optimization method and probability method the utilization rate of throat capacity, and further considers the effects of different confidence level of delay time and stochastic change of operation time of throat capacity, tests the validity of the model and the probability of stochastic optimization algorithm.