Research On Spatial Layout And Optimization Of Railway Freight Network In Tangshan City Based On POI Data

With the reduction of mineral resources due to mining,the continuous construction of railways and roads,and the continuous adjustment of the layout of related industries,some railway freight outlets have lost customers and insufficient supply,especially in resourcebased cities.As a typical representative of resource-based city transformation,Tangshan’s three stages of development can be represented by "constructed by coal,prospered by steel,and strong by sea map".Tangshan coal will face depletion in decades,the existing large iron and steel enterprises will retreat to the city and relocate to reduce production capacity,and the layout of the iron and steel industry will be adjusted to the coast.However,the existing network layout is similar to the layout after the railway freight reform in 2013.The network layout planning is relatively lagging behind,and the distribution of resources such as freight yards is uneven,making it difficult to give full play to its advantages in transportation resources.Therefore,this research takes Tangshan City as the research area and the freight network as the research object,and analyzes the existing railway freight lines and the spatial layout of the network from a spatial perspective.Tangshan Municipal Government provides decision support to improve the scientific layout of railway freight outlets.The main work of this paper is as follows:(1)Firstly,by referring to relevant literature and data,analyze the economic development status and mineral resources distribution of Tangshan in the study area,and then use QGIS software to preprocess data such as point,line,and surface.Due to the fact that coal resources may be exhausted after decades,the coal mining output of Kailuan Group in the urban area has declined to a certain extent.In addition,the pollution of key iron and steel enterprises will be withdrawn from the city,and some freight outlets will be affected in the future,and the supply of goods will be reduced in the future.(2)On the basis of vector data,the main freight lines in Tangshan City were sorted out,and it was found that after 2015,the Zhangtang railway,Tangcao railway and Shuicao railway were newly added in Tangshan City,and the freight lines changed greatly.Therefore,the focus is on sorting out the changes of railway lines after 2015 and calculating indicators such as the station spacing of each line.Based on the situation of field investigation,the present situation of Tangshan railway freight network is analyzed,and it is found that it faces the problems of policy dependence,declining supply of goods and insufficient logistics throughout the whole process.(3)Using the visual analysis method,the corresponding heat map was made for the freight network and enterprise POI data in Tangshan City.The number and scale of registrations of manufacturing companies,mining companies,and logistics companies show different spatial distribution characteristics.(4)In terms of the matching between the outlets and the needs of the enterprise,first generate the service area of each freight outlet based on the road network and calculate the area.According to the spatial distance,enterprises are clustered by k-means clustering method.Use two mobile search methods to calculate the accessibility of each demand point.It is found that the overall accessibility is good from southwest to northeast,while the accessibility of the northeast and southwest of Tangshan is poor.The coupling coordination model is then introduced to analyze the match between the outlets and the needs of enterprises.The results show that the degree of coupling and coordination in the central urban area of Tangshan is relatively high,followed by the northern area except Qianxi,which is barely coordinated,and the southern area of Tangshan City and Qianxi moderately.out of tune.(5)Finally,the location allocation model is used to obtain the optimized layout of the network facility table and draw a map to generate the optimized facility location plan.Based on the minimum facility model,52 facilities are obtained,of which the existing network is optimized from 41 to 28.The results show that when the service area is 20 kilometers,the existing railway freight network has a certain redundancy.