Effects of scour on natural frequency of offshore wind turbines and engineering treatment measures

Abstract

The offshore wind turbines will continue to be subjected to complex loads such as wind, waves and current in the marine environment during operation, resulting in local scour holes of pile foundation, which then affects the natural frequency of offshore wind turbines and harms its safe operation. Therefore, based on engineering and numerical methods, this paper studies the influence of local scour holes on the natural frequency of wind turbines and puts forward engineering treatment measures after serious scour. The results show that as the scour depth, range, or angle of the scour hole decrease, the natural frequency of the wind turbines diminishes. The high-rise pile cap foundation reinforcement can have apparent effects on controlling the structural deformation, increasing the first-order natural frequency of the structure, and reducing the flange's inclination, which has practical engineering value.