A seismic resilience assessment framework for urban interchanges considering system functionality loss and recovery

Abstract

Interchanges are critical nodes in urban transport networks, and their seismic resilience is key to effective emergency response and recovery. However, current assessment methods focus on individual bridges, overlooking functional interdependencies within interchanges. Recovery models are often based on damage states and engineering judgment, which may not reflect actual restoration processes. To address these limitations, this study proposes a resilience assessment framework that accounts for both systemic functionality loss and recovery. Firstly, the interchange functionality is divided into safety and traffic functionality, systematically integrated through a hierarchical belief rule-based approach. The safety functionality is evaluated using system fragility, while the traffic functionality accounts for component functional dependencies and the impact of network traffic flow characteristics on performance. Secondly, the duration and functionality status at each stage of the restoration process are determined by integrating the repair time of each performance group with a segmented and hierarchical construction strategy. Subsequently, the Monte Carlo method is employed to compute the resilience index through multiple simulations. Finally, the proposed framework is applied to an example interchange, with results compared to those from traditional, expert-based methods. While traditional approaches show considerable variability, the proposed method produces intermediate results that balance these differences. This framework offers a reliable, system-level approach for assessing interchange seismic resilience and informs decisions on retrofitting, emergency response, and resource allocation.