Optimization For Urban Rail Transit Train Plan Under The Mode Of Full-length And Short-turn Routing And Express And Low Train

Urban rail transit has developed rapidly due to its inherent advantages of speed,high efficiency,energy conservation,environmental protection,safety and small footprint,making China the largest urban rail transit construction market in the world.In the face of the growing and rapid development of urban rail transit,how to reasonably utilize the existing rail transit resources and give full play to its transport capacity has become a hot issue.Reasonable train operation plan is the basis of organizing all kinds of passenger transport work in urban rail transit and the key to make full use of rail transit line resources.According to the uneven distribution of passenger flow in subway lines,many lines in China implement the operation and organization mode of full-length and short-turn routing,which increases the travel time of long-distance passengers.In order to solve the problem of long distance passenger travel time,some cities have adopted the model of express and low trains,which obviously fails to take into account the uneven distribution of passenger flow.In order to overcome the defects of these two modes,this paper puts forward a mode that combines large and small intersections with fast and slow vehicles,and optimizes the operation scheme under this mode.This paper introduces the concepts and applicable conditions of the two modes: full-length and short-turn routing and express and low train.Firstly,the optional path and path utility value of different passengers are analyzed.Logit model is used to calculate the probability of different path choices,which lays a foundation for calculating the travel cost of passengers.And then to train frequency,express stop plan and small road turn-back station location as decision variables,the total cost and enterprise operation cost to passengers as objective function,considering the line capacity,capacity and traffic demand,build the double nonlinear mixed integer programming model,and according to the ideas of the simulated annealing algorithm for design.This paper mainly does the following work:(1)this paper expounds the research background and significance of the optimization of subway operation plan under the combination of full-length and short-turn routing and express and low train modes,summarizes the research status,and introduces the concepts,advantages and disadvantages of the subway transit and fast and slow train modes and their applicable conditions.(2)An optimization model is established for the research object.Firstly,it analyzes the influencing factors of passengers’ travel path choice behavior,classifies passengers according to the return-station location of short-turning and the starting and ending points of passengers,enumerates the alternative paths of all kinds of passengers,and uses Logit model to calculate the probabilities of all kinds of passengers choosing different paths.Then,the total travel costs of all passengers and the operating costs of the business are calculated.Finally,from the perspective of the game,the balance of interests between passengers and enterprises is sought,so as to minimize the enterprise’s operating costs and passenger travel time.The dual objective mixed integer programming model is constructed by taking the transportation cost of the metro operation department and the minimum passenger travel time as the objectives,and considering the actual transportation capacity of the line,the stopping limit and the turn-back condition as the constraints.(3)By using the unified dimension of income method,the two-objective model is transformed into a single-objective model.According to the characteristics of the model and the situation solved,the simulated annealing principle is used to design the algorithm to solve the model.(4)Taking Nanchang rail transit line 1 as a case study,this paper analyzes the passenger flow characteristics and ride reduction of each station,and finds that Nanchang metro line 1 is suitable for the traffic organization mode of combining full-length and short-turn routing with express and low train.By using the algorithm of the model and design,it is found that the traveling scheme under the mode of combination of large and small roads and fast and slow cars increases the waiting time of passengers,but reduces the traveling time of passengers,thus reducing the travel time of passengers and the cost of enterprises.It optimizes the travel experience of long-distance passengers,reduces the operating cost of the enterprise,and realizes the win-win situation between passengers and the enterprise.