| In recent years,China has entered the stage of accelerated urbanization,whether the urban road network planning reasonable is a prerequisite for the rapid and good development of a city.And all kinds of national regulations are gradually updated,"Code for transport planning on urban road" is still in use after 20 years,the consideration of the terrain in the code is simple and has not been quantified,and the terrain has a great limit in urban construction.How to determine the reasonable density of the road network base on the topographic information is particularly important.This paper makes use of the powerful spatial analysis ability of GIS and Matlab and SPSS’s powerful mathematical analysis ability,according to the data of 2020 urban master planning or transportation planning of typical small mountain cities,establishes the small mountain city road planning decision model and the small mountain city road network density model,in order to provide theoretical basis for a new round of urban planning or new town planning for small mountain cities.Firstly,the paper defines the concept of the mountain city,then on the basis of the analysis of the differences and links between the various types of norms,the small mountain cities are graded according to the urban resident population.Through the qualitative analysis and correlation analysis,the slope,aspect,slope of slope,and relief are selected from the terrain factors of small mountain cities.Secondly,according to the principle of dynamics and mechanics,the relevant standards,the terrain factor indexes are classified to analysis the characteristics of the slope,aspect,slope of slope,and relief of small mountain city.The evolution process of the spatial structure and the characteristics of the road network in the small mountain cities are summarized,analysis of small mountain city road properties from three aspects of horizontal,vertical and horizontal;analyzed the spatial distribution characteristics of the urban road network density in the small mountainous’ terrain factors area.Then,on the basis of analyzing the mechanism of urban road planning,urban scale,slope,aspect,slope of slope,relief,land use and current road are summarized of the influence factors.Set up the model of road planning decision based on terrain by using the binomial logistic model;make the use of SPSS to determine the various parameters of the model,through various test,verified the applicability of the model,and its application in GIS.At last,the relationship between the length of the road and the influencing factors of the small mountain city is established by using the BP neural network model;the calculation method of road network density is determined according to the dividing range of small mountain city road service land;based on the actual situation,the recommended values of the road width at all levels in small mountain cities are given;determining the demand of road network,and through typical small mountain city in 2030 urban master plan or comprehensive traffic planning data for example analysis,compare to the actual planning road network density and the results of this model,recommended levels of small mountainous city road network density value. |
