Stage-Coupled Failure in Metro Station Emergency Management Under Compound Hazards: Implications for Urban Infrastructure Resilience

Metro station emergencies are increasingly characterized by compound hazards, where multiple disruptions interact across emergency management stages. Existing approaches typically focus on technical failures or isolated stages, overlooking how management processes themselves can generate and amplify system-level risks. This study introduces the concept of stage-coupled failure, which explains how failures propagate across preparedness, response, and recovery through interdependent management mechanisms. A theory-building approach is adopted, combining systematic literature synthesis with scenario-based analysis. Four coupling mechanisms—resource, information, organizational, and temporal—are identified to structure cross-stage interactions. A semi-quantitative representation is further proposed to capture feedback loops and nonlinear dynamics. The findings show that failure escalation is driven by cross-stage interactions rather than isolated breakdowns. The proposed framework provides a new perspective for understanding compound hazard dynamics and supports applications in safety assessment and emergency management planning.