Characteristics and Seismic Resilience of Trunk Highway Network in Handan Area

To accurately assess the structural characteristics and seismic resilience of the trunk highway network in Handan, a network topology model was developed using both primal and dual approaches. The analysis focused on structural attributes and centrality indicators, with the relative size of the largest connected subgraph and global efficiency adopted as key robustness metrics. Several pre-earthquake attack strategies were implemented, including random attack, degree-based attack, betweenness-based attack, and their dynamic variants, to simulate the network's response under different scenarios. A post-earthquake attack model was also established using a historical earthquake in Cixian and a hypothetical seismic event. Nodes were attacked based on their peak ground acceleration (PGA) values to analyze the impact of affected area size on network robustness. The results show that the Handan highway network exhibits scale-free characteristics but does not display small-world properties. Nodes in the central region generally have high degree and betweenness centrality values (above 0.8), indicating stronger connectivity compared to peripheral areas, where betweenness centrality is typically below 0.25. Among the pre-earthquake strategies, dynamic betweenness attack caused the most severe degradation of network robustness. In post-earthquake scenarios, robustness declines as the PGA-based impact area increases. This study offers insights for improving the seismic resilience of transportation infrastructure in Handan and provides a methodological reference for robustness analysis under similar disaster scenarios.