Use of isochrone maps to assess the impact of high-speed rail network development on journey times: a case study of Nanjing city, Jiangsu province, China

ABSTRACTIt is well known that the increasing development of transport infrastructure will result in temporal and spatial convergence. As an important component of China’s high-speed rail (HSR) network, an ambitious HSR building program in Jiangsu province will extend the network to cover all cities and 95% of counties by 2030. This study aims to present and analyze the impacts of the evolving HSR network in Jiangsu province over the period of 2010–2030 by developing multi-phased isochrone maps of Nanjing city (the provincial capital of Jiangsu province). During the process, layered cost distance, a new method based on a door-to-door approach in actual travel time calculations, is proposed in order to draw the maps at a more detailed geographical level. Our results are expected to facilitate proactive public policy decisions related to improving the transport network.