利用成本加权栅格法分析非高铁与高铁条件下长三角地区5大都市圈的最短旅行时间的可达性和一日交流圈等时圈格局变化。结果显示:1都市圈高铁站点城市成为时间收敛最大受益者,非站点城市可达性也有所提高,但幅度较小。25大都市圈等时圈均沿高铁线呈轴向态势向外推移明显,表明高铁对都市圈空间拓展具有较强的轴向引导作用。3高铁扩展了5大都市圈一日交流圈范围,覆盖范围几乎达到100%,1h和2h等时圈覆盖范围均有不同程度扩展,表明高铁条件下,都市圈内部城市以及都市圈之间重要核心城市的时间距离拉近,实现跨城市当日流动,形成"同城效应"。
This paper integrated method of cost weighted raster analysis was designed and applied to generate five metropolitans’ daily communication rings with and with the operation of high- speed railways in Yangtze River Delta region. The valuation of accessibility was conducted with a coefficient based on the shortest travel time. After the valuation, differences between accessibility patterns with scenarios with and without high-speed railways were analyzed,and influences of the high-speed railways on five metropolitans’ accessibility were discussed. The results indicated that cities along the high- speed railways became the biggest beneficiaries of time convergence, the accessibility of none station cities also promoted while in minutely. The isochronous rings of five metropolitans evolved outward along the high-speed railways, and the spatial scope showing the extend trend along the high-speed railways. High-speed railways would expand the isochronous ring, and the coverage of five metropolitans’ daily communication ring almost attained one hundred percent in scenario of high- speed railway. The coverage of 1 and 2 hour- isochronous rings extended in varying degrees. This indicated that daily flow across the cities, and"City effect"can be achieved with the closer time distance among main cities inside or outside the metropolitans.