Research On Issues Related To High-speed Rail Express Transportation Under Passenger Car Piggyback Mode

With the development of the express industry,the rapid growth of medium and long-distance transport demand,fast,on-time,low-cost,low social environmental impact of high-speed rail express transport competitiveness continues to grow,has a huge market prospects.China’s high-speed rail express transport is in its infancy,passenger car piggyback mode as the main mode of transport,high-speed rail transport program and urban distribution decisions are greatly affected by the passenger transport plan.Therefore,it is of great significance to promote the development of high-speed rail express transportation by coordinating and optimizing high-speed rail express transportation in passenger car piggyback mode,designing high-speed rail transportation scheme and optimizing urban distribution decision from the overall perspective.In this paper,firstly,on the basis of domestic and foreign research related to highspeed rail transportation and urban distribution,research ideas and framework are proposed;secondly,the theory and modeling methods related to high-speed rail express transportation are introduced,the overall operation process of high-speed rail express transportation is described,and high-speed rail transportation and urban distribution are analyzed,laying the foundation for the subsequent research;thirdly,the operational process of high-speed rail transportation is analyzed,a three-layer space-time-state network is constructed,and the shortest transportation time is the objective.Fourth,describe the urban distribution process of HSR express transportation,combine the road section correlation and real-time road conditions to dynamically estimate the transportation time,determine the arrival time window according to the HSR schedule,and select the arrival time window and transport time as reference points,consider the influence and feedback between transport start time and path selection,and establish a joint decision model of high-speed rail express urban distribution based on prospect theory.Finally,the validity and reliability of the model are verified by taking key cities in Yangtze River Economic Belt as examples.The results show that the design model of high-speed rail transportation scheme takes into account the actual operational requirements and the time frame requirements of different express products,which makes the final scheme more compatible with the transportation demand;the Lagrangian relaxation algorithm converges faster and can obtain high-quality feasible target values in a short time;the dynamic estimation model of path transportation time can well reflect the distribution of transportation time in the real situation;different product types will have different effects on the decision process and decision results because of different time reliability;the joint decision of highspeed rail express urban distribution takes into account the mutual influence between transportation start time and path selection in the decision process,which is more compatible with the real situation.