Evaluation of Multi-Dimension Accessibility of Intercity Road Networks from the Perspective of Regional Coordinated Development

The accessibility of intercity road network is a key indicator for measuring the efficiency of regional flows of economic and social resources. However, the existing researches mainly focus on macro-level connectivity, while local services and economic interactions between nodes receive less attention, thus providing insufficient support for regional coordinated development. To address this issue, this paper proposes a multi-dimension accessibility evaluation framework for intercity road networks. First, a node classification method is developed to balance regional coordinated development goals with data availability, systematically defining the positions and functions of economic activity centers, transportation hubs and tourist attractions within the network. Secondly, expressways, national highways and provincial highways are integrated into a unified topological model, and a time impedance adjustment mechanism that accounts for both travel efficiency and cost differences is established, which is used to capture the dynamic balance characteristics of different road types in path selection. On this basis, three accessibility evaluation models are constructed respectively from the dimensions of connectivity, service and economy, and are used to quantify the overall network connectivity, residents’convenience in accessing hubs and attractions, and the strength of economic interactions between nodes, respectively. An empirical analysis of the Guangdong-Hong Kong-Macao intercity road network at the end of 2021 shows that the Greater Bay Area significantly outperforms Eastern, Western, and Northern Guangdong in terms of multi-dimension accessibility. Based on the principles of evidence-based design, the selection of key nodes and the planning and construction of high-standard roads lead to significant improvements in connectivity, service, and economic accessibility, both across the entire region and within Eastern, Western, and Northern Guangdong. Specifically, 99.2% of nodes in Eastern, Western, and Northern Guangdong show improved connectivity accessibility, and 83.3% exhibit enhanced economic accessibility, thus fully validating the effectiveness of the proposed evaluation framework and the optimization scheme. This study provides a systematic tool and decision-making reference for regional road network optimization and resource allocation.