特大城市空间形态差异对交通网络效率的影响

Influence of Different Spatial Forms for Metropolitans on Transportation Network Efficiency

以交通网络出行迂回作为交通网络效率分析的切入点,选取形状指数、紧凑度作为空间形态分析指标,对特大城市空间形态布局进行类型划分,并挖掘各城市交通网络效率空间分布差异特征,基于多元回归模型剖析中国各特大城市空间形态布局与交通网络效率之间的影响关系。研究表明:(1) 5种类型城市交通效率高低分布差异明显,紧凑圆形城市边缘区交通网络效率较低,而非紧凑带形交通效率低的区域多分布于城市核心区,紧凑方形城市交通网络效率高地区分布较为集中,而非紧凑方形交通效率低的地区分布较为分散,紧凑带形城市面积越小则交通效率越高。(2)就城市空间布局与交通网络效率影响关系而言,随着城市形状指数的增大,城市交通迂回值未进一步增大,说明城市形态布局接近圆形均匀分布时,其城市交通网络效率较高;随着城市紧凑度值的增加,城市交通迂回程度值亦不断增加,说明城市形态布局程度越紧密,反而其交通网络效率越低,当城市形态布局紧密程度适中时,交通网络效率水平较高。

With the rapid urbanized for Chinese metropolitans, the expansions of urban space are influenced by the efficiency of transport network, which means the different of megalopolises have been plagued by different degrees of travel congestion. By taking transportation network travel circuity as the entry point of transportation network efficiency analysis, the shape index and compactness are selected as indices of spatial morphological analysis in this paper. Then the spatial morphological layout of metropolitans is divided into types, which means spatial form layout of metropolitans is classified by urban form index. At the same time, it also tries to excavate the spatial distribution difference characteristics of urban transportation network efficiency. Finally, based on the multivariate regression model, the relationship between the spatial morphological layout of China's metropolitans and the efficiency of transportation network is analyzed. The result shows that the distributions of transport efficiency in five types form of metropolitans are obviously different. Low efficiency of transportation network for compact circular cities are in urban fringe areas and low efficiency of transportation network for non-compact belt cities are mostly distributed in the urban core areas. High network efficiency area distribution of compact square cities is more concentrated. The low network efficiency area distribution of noncompact squares cities is more dispersed. The smaller the size of the compact belt cities, the higher the transport network efficiency. It can be found out that with the increase of urban shape index, the urban transport circuity has not been further increased, which means that when the urban form layout is close to the circular uniform distribution, the urban transport network efficiency is higher;with the increase of urban compactness, the value of urban transport circuity is increasing, which shows that when the urban form layout is more compact, but the efficiency of transport network is lower. It means that the efficiency level of transport network is higher when the urban form layout is loose. What are the differences in urban traffic efficiency layout caused by the difference of spatial form in metropolitans? What is the relationship between the spatial form of metropolitans and the impact on transportation network efficiency? Under the influence of the rapid development of the construction environment of metropolitans, these two key issues have become the focus of this study. This article studies the transport network efficiency under the difference of spatial form layout, which can help to analyze and improve the travel efficiency of metropolitans.