Identification of the modal and structural properties of a high-rise scale model

The fundamental natural frequency of high-rise buildings is crucial for predicting wind-induced vibrations that affect living and working conditions. It is often underestimated during design. To explore the discrepancy between predicted and measured natural frequencies, model updating was applied to several Dutch high-rise buildings. This revealed challenges in estimating building and foundation stiffness reliably using model updating. A laboratory experiment with a scale model was conducted to replicate in-situ interactions and generate modal property data for different structural configurations. Model updating was applied to configurations with a fixed, stiff spring, and soft spring base. Results show that increased base flexibility makes shear stiffness estimates highly sensitive, while axial stiffness remains stable. These findings suggest that model updating can estimate in-situ rotational foundation stiffness effectively but is less reliable for horizontal stiffness. Future research will extend these investigations to both the test structure and in-situ buildings.