Hysteretic energy-based seismic loss assessment for reinforced concrete buildings considering the impact of ground motion duration

Ground motion duration significantly influences the cumulative seismic damage of reinforced concrete (RC) buildings, yet current design codes and assessment methodologies generally do not adequately account for this effect. This paper develops a hysteretic energy-based seismic loss assessment method within the Performance-Based Earthquake Engineering (PBEE) framework to incorporate the influence of ground motion duration. Hysteretic energy is employed as the engineering demand parameter (EDP) to quantify cumulative damage. A Bayesian probabilistic approach is used to develop capacity models that convert conventional deformation-based limit states into equivalent energy-based thresholds. The framework is applied to two representative RC frame buildings designed for different seismic design levels. A total of 140 pairs of spectrally equivalent short- and long-duration ground motions are selected as seismic input motions. Results show that long-duration ground motions substantially increase seismic demands and shift the dominant damage states from repairable conditions toward demolition or collapse. Compared with short-duration ground motions, long-duration ground motions increase seismic losses by 20%–36%, regardless of whether site-specific seismic hazards are considered. When site-specific seismic hazards are incorporated, the expected annual loss (EAL) exhibits more complex trends. Under identical seismic hazard conditions, higher seismic design levels reduce the EAL by 17%–30%. However, when each building is evaluated under its site-specific seismic hazard, a building designed to a higher seismic level but located in a high-hazard region may exhibit a greater EAL than a building designed to a lower seismic level but located in a low-hazard region. These findings highlight the importance of incorporating ground motion duration into seismic performance assessment and demonstrate that seismic hazard remains a dominant factor affecting annual loss estimation, with implications for risk-informed design, earthquake insurance, and regional seismic loss modeling.