Abstract: Wind-induced fatigue is a long-term accumulation process, and a single wind load event may not cause immediate damage to the structure. The interaction between different materials and components, stress concentration, local stress, and other factors affect the stress relationship of the tower, making it difficult to analyze the aerodynamic loads in different directions. Therefore, the accuracy of identifying fatigue life is poor. A method for identifying the wind-induced fatigue life of onshore steel-concrete hybrid wind turbine tower is proposed. The SESAM/GeniE module is adopted to convert the actual structure into a finite element model and calculate the aerodynamic loads in different directions of the tower. Then the comprehensive load value is obtained by combining the aerodynamic loads; by analyzing the relationship between external load and fatigue life of the tower and accumulating the comprehensive damage value, the identification result of wind induced fatigue life of the tower can be obtained. The experimental results indicate that when applying the identification method described in this paper to identify the fatigue life of steel-concrete hybrid wind turbine towers, the fatigue damage amount of towers at the same node also changes with the continuous increase of wind speed. The root mean square of the stress response between the identification results and the actual situation is low, indicating that this method can obtain high identification accuracy.

Key words: steel-concrete hybrid wind turbine, tower, wind-induced fatigue, life identification, aerodynamic loads