While current seismic design primarily aims to ensure life safety during major earthquakes, growing societal demand has shifted the focus toward resilience performance, emphasizing early functional recovery and reduced downtime. A critical issue is to evaluate the impact of both the delay time before repair initiation and the repair time of structural and non-structural components on downtime. This study investigates how cumulative deterioration caused by repeated seismic events during the service life of RC buildings influences downtime after a major earthquake. Furthermore, a machine learning-based importance analysis is conducted to identify key factors influencing downtime, supporting effective recovery strategy development.
