The Study On Accessibility Of Road Networkin The Main Urban Area Of Lanzhou

In recent years,with the rapid development of China's economic construction,urbanization has also entered a rapid development stage,the scale of cities is constantly expanding,urban people,traffic,economic flow and information flow are highly converging,most of which depend on urban road transportation to complete.Therefore,the development of China's economic construction not only promotes the rapid growth of urban traffic,but also promotes the construction and development of urban road network and its facilities,and the construction of urban road network supports the development of urban social and economic development,boosting the process of urbanization and producing more material flow.So the accessibility of urban road network affects not only the transport efficiency of urban material flow,but also the sustainable development of urban social economy.The accessibility of urban road traffic network is an important concept to characterize the effectiveness of urban road network.To a certain extent,it reflects the strong and weak connectivity of each unit in urban space,and affects the potential and competitiveness of the future development of each unit.The accessibility of urban road traffic network is not only influenced by the scale,grade and spatial structure of the road,but also closely related to the relationship of human road and vehicle road,such as whether the allocation of urban traffic line organization and transfer station is reasonable,and whether the traffic line organization and the spatial and temporal dynamic law of the inside and outside of the city whether it is reasonable and coordinated,and whether traffic management is scientific or not.Taking Lanzhou as an example,and taking the road network of the main city as the research object,this paper use three ways of accessibility analysis which are the shortest time distance model,the space syntax and the public traffic index method,makes a comprehensive analysis from three aspects of the geometric network,topological network and relation network of urban roads,and systematically analyzes the characteristics and problems of the road network in the main city of Lanzhou,and is expected to provide reference for alleviating urban traffic problems.The conclusions of this paper are as follows:(1)The accessibility of the geometric network in Lanzhou has an outward extending pattern in both the municipal and the district level,which has a distinct distribution characteristic of the central periphery,The average geometric network accessibility of the main urban area is 15.8.In partition level,the average geometric network accessibility of the Chengguan area is 7.22,the average geometric network accessibility of the Qilihe district is 6.93,the average geometric network accessibility of the Anning area is 6.66,and the average geometric network accessibility of the Xigu area is 7.55,a relatively independent road network is formed in the four zone,reflecting the division and influence of the special Valley space in the main urban area of the Lanzhou city to the main urban road network.(2)the connection degree and control degree of the main urban area of Lanzhou reflect the overall low traffic choice level.The east-west high selectivity road is strong and north-south high selectivity road is weak.The global integration degree(Rn)and local integration(R3)show the spatial distribution characteristics is high center and low peripheral.The center is mainly between the West Station in Qilihe District and the Dongfanghong Square,Xijinxi Road(0.899)has the highest value.The high value road of the four districts road network is mainly the main road in each area,and the integration degree is gradually reduced from center to the periphery.The overall intelligence degree(0.2785)reflects the low connectivity perception of the main road network in Lanzhou,and the strong sense of connectivity in the four district(higher than0.5).(3)The bus line repetition coefficient(1.027)in Lanzhou main city is lower than the 1.25-2.5standard,the bus line non zero degree(0.56)and the bus station coverage rate(44.76%)are low,the bus flow load is too focusin Xijindong Road and Xijinzhong Road,the transit line density of the Anning district and Xigu district is not up to the standard,the spatial distribution of the bus station service person and the site space is not match.