京沪高铁影响下的区域公路可达性空间分异特征研究

Impact of the Beijing-Shanghai high-speed rail on the spatial pattern of the regional road accessibility

在GIS技术和空间数据库支撑下,应用最短路径算法与网络分析技术及可达性指数,测度高铁通车前后案例区公路可达性空间格局与变化,采用变异系数与斯皮尔曼等级系数测算高铁的公平性影响.结果显示:①高铁从整体上提高区域公路可达性水平,极大地缩短中心城市间的时间距离,但各地可达性收益不等,可达性均衡程度降低.②高铁塑造高可达性"走廊"与"岛".加权旅行时间高变率地区呈现出"哑铃状",表明高铁沿线站点地区与南北端城市获益最多.经济潜力与日常可达性高值区向高铁沿线城市偏移,反映站点城市接收中心城市辐射能力提高;高铁沿线城市日常可达人口规模急剧膨胀,扩大沿线城市服务业的市场范围.③高铁站点依靠其在快速交通网络节点的枢纽作用,将成为区域重要的快速交通中转站.

This paper discussed the spatial differentiation of the road accessibility under the effect of Beijing-Shanghai high-speed rail （HSR）. Firstly measured accessibility changes in the spatial distribution of four different accessibility indicators, computed and mapped using a GIS support. The accessibility maps described both the possible benefits and their spatial distribution of the region. Sub- sequently measured the transport equity by calculating a set of inequality indices of the accessibility dis- tribution and estimated whether the disparities in regional accessibility are increased after the implemen- tation of the HSR. Finally we applied the GIS based technique to calculate the service population scaleof every station. The results showed that the HSR obviously improve the overall road accessibility level, re- ducing greatly total travel time among the central cities. However, it leads to more polarized ac- cessibility patterns of the spatial development which indicated that various regions obtain unbal- anced accessibility gain from the HSR, establishing ＂island＂ or ＂corridor＂ spatial patterns with the highest lever accessibility which replaces the ＂ellipse concentric circle＂ shape of road accessi- bility spatial structure. In addition, the HSR contributes to enlarging the service market demar- cation and broadening regional labor markets of main central cities along the line in short time distances and promote many urban agglomerations to facilitate co-operation. Moreover, the HSR stations become the rapid traffic network nodes and the hub of the social and economic activities.