This paper presents a procedure for the wind load identification and the results of its practical application. The wind loads are inversely reconstructed in time domain from measured structural response by means of an augmented impulse response matrix. The inherent noise amplification arising from the ill-posed inverse problem is resolved through Tikhonov regularization. In order to increase the accuracy in solving the inverse problem along with the availability of the measured response just at a limited number of sensor locations, the problem is projected onto the modal coordinates. Consequently the modal wind loads are identified in modal subspace for several single degree of freedom systems, whose characteristic parameters are obtained by an operational modal analysis procedure. The structure under measurement is a 9.1 m (30 ft) tall guyed mast consisting of tubular elements. Since the direct wind pressure/load measurements on the structural members are almost impossible in full-scale testing, numerical simulation was also implemented to verify the results of experimental load identification by analogy. The load identification results are provided in time and frequency domain. Numerical simulation, where actual loads are available, confirm the capability of the method in identification of modal wind loads. Then based on the existing analogy between the simulation and practical application results, the identified loads from field measurements are validated.
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