How interdependent coupling affects the resilience of urban critical infrastructure(UCI)

Urban critical infrastructure systems do not exist in isolation. They are interdependent and interact with each other, constructing a multilayer network model can effectively and accurately simulate the relationship between these systems, to better understand and analyze their interactions and impact on the overall resilience of the system. This study constructs eight different coupling-type multilayer cascading failure models to explore the robustness patterns of interdependent coupling networks under two different coupling patterns (chain and triangle) and different coupling ratios. The research results indicate that (1) both chain and triangle coupling networks exhibit optimal adjustable capacity parameter values, but the optimal adjustable capacity values for these two coupling patterns are not the same; (2) the robustness of the triangle coupling network is superior to that of the chain coupling network, although, under degree-matching coupling types, the robustness of the two coupling patterns is similar; (3) under the same coupling pattern, different coupling types of multilayer networks exhibit differences in robustness, and the optimal inter-layer coupling types vary within different coupling ratio ranges; (4) under different coupling patterns, for the same coupling ratio range, the optimal inter-layer coupling types also differ. These findings provide a foundation for more precise modeling, thereby enabling the development of more effective strategies to enhance the resilience and reliability of interdependent urban critical infrastructure systems under varying coupling conditions.