Study On Location Selection Of High Speed Rail Express Hub Based On The Value Of Freight Travel Time

With the continuous development of high-speed railway construction with "eight vertical and eight horizontal" channels in China,the radiation capacity of high-speed railway network has been enhanced,which has laid a good infrastructure for the development of high-speed rail transit.At the same time,driven by the rapid development of e-commerce market and new types of business such as flash delivery and timely distribution,the quantity of high-efficiency,high added value and high-quality express goods is increasing constantly,which puts forward higher requirements for the timeliness and economy of the express industry transportation.As a new type of fast transportation mode,the rapid development of high-speed rail express service has created a new opportunity for the improvement of the timeliness and economy of express transportation and the improvement of the network system of express transportation.Based on this,the location of high-speed rail transit hub can not only effectively improve the operation efficiency of the high-speed rail express system,but also improve the overall timeliness of China’s express market,and promote the rapid development of the high-speed rail express network.Therefore,this paper aims at the 24-hour timeliness of goods in China,which is proposed by China’s transportation power strategy,and 200 prefecture level administrative regions that have been connected with high-speed rail in China as the research object,and conducts the research on the location of single hub and complex hub of high-speed rail express,including the following contents:(1)Comprehensive evaluation of hub location based on freight time value.Firstly,on the basis of the research on the concept of freight time value and its influencing factors,the evaluation system of high-speed rail hub location is constructed,including three categories and eleven indicators,and the comprehensive layout coefficient of each candidate city is calculated by factor analysis method.Then,according to the value characteristics and time sensitivity of express goods,the express goods are divided into four categories,and the average value and proportion of each category of goods are calculated.The average value and proportion of each type of goods are measured,and the logit model and gravity model are used to carry out inter-city high-speed rail express transportation.OD freight volume forecast.(2)Research on the site selection of a single hub based on the high-speed rail network.In order to solve the research problem of single hub location based on high-speed rail network,a P-median hub location model with limited coverage distance is established.The model is solved by a hybrid intelligent algorithm combining genetic algorithm and particle swarm search algorithm.The results show that the spatial layout and service area of the hub basically match the scope of various urban agglomerations in China,and each urban agglomeration has1-2 high-speed rail express hubs to serve it.Due to differences in economic development and traffic conditions in various urban agglomerations,there is a large gap in average transportation timeliness.The average transportation time from cities in the eastern region to the hub is 0.47 h,the average transportation time from cities in the central region to the hub is0.95 h,and the average transportation time from cities in the western region to the hub is 1.09 h,and the hub is in the east,middle,and west 3:1:1 The number of hubs is similar,indicating that the number of express hubs in the region directly affects the timeliness of express services in the region.(3)Research on the site selection of a composite hub relying on the air-rail combined transport network.As the results of the single-hub site selection based on the high-speed rail network show that the high-speed rail express alone cannot meet the domestic 24-hour timeliness goal,further research on the site selection of the composite hub relying on the airrail combined transport network is carried out.On the basis of single hub site selection,considering the impact of freight time value on hub site selection,an air-rail intermodal hub site selection model was established,and the model was solved by genetic algorithm.According to the results of the site selection of the air-rail combined transport hub,it can be seen that the location of the composite hub has obvious regional differences.The purpose of setting up hubs in the northeast,northwest and southwest regions is to improve the timeliness of regional express delivery,while the purpose of setting up hubs in the eastern coastal areas is to reduce express delivery costs.From the perspective of the distribution of urban agglomerations,air-rail intermodal transport hubs are set up in all major urban agglomerations.The location of the hub is closely related to economic and transportation location factors.It depends on the core cities of the urban agglomeration and has the foundation and conditions for forming a hub-and-spoke network.In the context of high-speed rail network operation and gradual improvement of the system,scientific and reasonable selection of high-speed rail express delivery hubs can not only improve the operational efficiency of the high-speed rail express system,promote the rapid development of the high-speed rail express network,and improve the overall timeliness of the Chinese express market,but also Make full use of existing facilities to enhance the competitiveness of the high-speed rail express market,maximize the comprehensive benefits and radiation range of the high-speed rail express delivery hub,and provide scientific guidance for the construction of China’s high-speed rail express service network and space optimization.