Research On Northwest Five Provinces Railway Network Expansion Law Based On GIS

Railway plays a supporting role in the development of national economy on transport,and it's irreplaceable in population migration,resource development,economic and social development.But at the same time,railway development is also highly coupled with the population and economic development along the line.The five provinces in Northwest China has always been less populous,and its economic development lags behind the national level.So the infrastructure construction is relatively backward,which has become an important factor restricting the economic development along the line.At present,the scale of railway network in this area is still small,especially the operation lines of high speed railway are only two lines within 250km/h,which are within 250km/h of the design speed of Lanxin and BaoLan Passenger dedicated line.There are also problems such as low design standards of existing lines and difficult operation efficiency.In the "Long-term railway network planning" approved in 2016,the government put forward clearly to build "The Belt and Road" international channels,including the construction of a number of poverty alleviation and development of railway land.The western railway construction ushered in new opportunities for development.It is necessary to study the relationship between the population,economy and road network expansion,make the scale of the road network explicit at different stages,and design the line time scientifically to achieve the mutual coordination of investment and development.On the platform of ArcGIS,the paper analyzes the relationship between the road network expansion and the development of population and economy in Northwest China for many years,and studies the law of expansion of railway network in the five provinces in Northwest China.The main research work is in the following aspects:(1)Construction of railway network forecasting modelOn the basis of the general expansion theory of railway network,a variety method of measuring the railway network scale were analyzed.The railway destiny method and accessibility method are selected as the evaluation index of railway network state,and the research ideas of mutual promotion between railway and economic development are adopted.The law of interaction between the railway and the economic development is analyzed,and the railway economy coordinate coupling degree model is established..(2)Construction of railway network database for five provinces in Northwest China based on GIS.Combining the research needs of the railway economic coordinated coupling degree model,taking into account the distribution characteristics of the railway lines,taking the data of line data,station site distribution,administrative division data,population and economic data as the basic data along the railway,integrating DEM and remote sensing images,through series projection transformation and topology error correction,a railway network database of northwest five provinces is constructed,which contains a large number of vector and raster data.In order to simplify the analysis,according to the existing railway station distribution,the clustering method is adopted to replace the regional station center with the city center,and the visual expression of the model is realized.(3)Adaptability analysis of provincial and regional road networkBased on the provincial administrative division,the correlation of population density,per capita GDP and railway network density was analyzed,and the correlation between the three was analyzed by Pearson correlation coefficient.The expression of railway network density is established based on Cobb-Douglas function,taking population density and per capita GDP as variables.The correlation calculation expression is used to analyze the adaptability of the road network in 2020 in the middle and long term railway network planning,and to evaluate the road network adaptability of the regional whole.(4)The rule of railway network expansion based on prefecture level city.In the five provinces of Northwest China as the research unit,the impact of the 1992-2017 year railway construction on the accessibility of the regions along the line is analyzed and compared year by year,and the corresponding relationship between the scale of urban development and the accessibility of the road network is sought,and the adaptability of the scale and timing of the railway construction and the urban planning and development is clearly defined.Based on the coupling degree,the railway economic interaction model is used to analyze the coordination coupling degree of road network and economy in different cities and cities.Taking the economic level in 2017 as the base point,the demand degree of road network is predicted,and the rationalization proposal is put forward for the implementation of the plan.