A model updating strategy to simulate structural dynamics of buildings under low‐intensity earthquakes

Abstract In vibration‐based structural health monitoring (SHM) modal parameters from operational modal analysis help assess structural safety condition, especially after earthquakes. Finite element model updating (FEMU) techniques provide support in analysing SHM data and enable more reliable previsions about the damage state of monitored structures. Linear modelling assumption is valid while the structure remains elastic but become unreliable after earthquake‐induced damage introduces nonlinear behaviour. This study examines how accurately the dynamic behaviour of an infilled reinforced concrete frame building can be simulated, under both ambient noise and low‐intensity earthquakes, using linear FEMU techniques. The study starts by analysing the building's real response to ambient and seismic excitations. The research then focuses on the calibration of FE models, using the Particle Swarm Optimization and following three FEMU approaches based on both pre‐event modal data and actual time history data from the earthquake. The accuracy of calibrated models in replicating the building's response is evaluated, also focusing on their usefulness for post‐earthquake assessment. Finally, optimisation outcomes for the three approaches are compared to assess the strengths and weakness of each.