Wind load identification using wind tunnel test data by inverse analysis

The method for modal wind load identification from across-wind load responses using Kalman filter is presented and verified using the wind tunnel test data. The Kalman filter is utilized for the inverse identification from limited measured responses and the closed-form of Kalman filter gain in modal space is derived for different types of measured response solving the Riccati equation. The wind induced responses used for the verification are measured responses from an aeroelastic wind tunnel test of a rectangular shaped concrete chimney. The displacement responses of the top part of the model are measured and used for the wind load identification, but the acceleration responses obtained by numerical differentiation of displacement are also used in order to evaluate the effect of response type on the identification result. It is found from the identification results that the proposed method identifies the modal across-wind load from measured responses with quite accuracy and the acceleration response yields more accurate wind load identification than displacement response.