Output-only Structural System Identification Method with a New Two-stage Kalman Filter and Incomplete Measurement

摘要

In this paper, a two-stage time-variant structural system identification method is proposed based on incomplete structural acceleration responses. In the first stage, an external excitation identification method is developed for time-variant structural system. The unknown structural response could be re-constructed in state space and regularization method. In the second stage structural parameter is identified and updated by Extended Kalman Filter. The re-constructed structural response and identified external excitation are used in the second stage. The proposed method is validated numerically with the simulation of a fifteen-story shearing structure subject to earthquake excitation. A model of a fourteen-storey concrete shear wall building was studied experimentally with shaking table tests to further validate the proposed method. The shear wall structure has a two-storey steel frame on top with base isolation. Results from both numerical simulations and laboratory tests indicate that the proposed method can be used to identify structural parameter and external excitations effectively based on the structural acceleration responses. The proposed method is capable to identify the dynamic load and structural parameters fairly accurately with measurement noise, numerical model error and environmental disturbances.