Wind-induced response and wind load identification of lattice towers considering the influence of rotational degrees of freedom

Lattice towers are widely used in infrastruetures. The acquisition of wind load and wind-induced responses is of great significance for evaluating the health Status of lattice towers. However, wind load is difficult to measure directly, and one of the ways to solve this problem is to reconstruet wind load indirectly through easily measured responses. The classical wind load identification method does not consider the influence of rotation, leading to the inaecurate identification results. A wind load identification method considering the influence of rotational degrees of freedom was proposed on the premise of knowing monitoring data. The dynamic displacement and modal information of the lattice tower were reconstrueted from the strain response, and then the Kaiman filter algorithm was utilized to calculate the velocity response and modal wind load. The mass matrix considering the influence of rotational degrees of freedom was established, and on this basis, the wind load of the strueture was identified. The numerical Simulation of the lattice tower verifies that the wind load reconstrueted by the method is highly consistent with the theoretical result in both time domain and frequency domain, and the mean value and root mean Square error at the highest measuring point are not more than 7%. A 54. 5 m high full-scale tower experiment further shows that the reconstruetion error of the proposed method for the actual strueture is generally within 10%. © 2024 Chinese Vibration Engineering Society. All rights reserved.