Dynamic Buckling Analysis of Wind Turbine Tower Under Near‐Fault and Far‐Fault Ground Motions

ABSTRACT

The wind turbine tower, a typical thin‐walled structure, is susceptible to buckling under dynamic loads, particularly during seismic events. The dynamic buckling behavior of wind turbine towers under near‐fault and far‐fault ground motions is investigated herein. A 2‐MW wind turbine located in northwestern China was selected as the prototype, with the blades and nacelle modeled as concentrated masses. For incremental dynamic analysis (IDA), 42 natural ground motion records were employed as input excitations, classified into three categories based on epicentral distance and pulse characteristics: 14 near‐fault pulse‐like ground motions, 14 near‐fault non‐pulse‐like ground motions, and 14 far‐fault ground motions. The dynamic buckling behaviors were analyzed by using phase plane trajectories and the Budiansky–Roth (B–R) criterion. A ductility factor accounting for dynamic buckling effects was developed. Local plastic dynamic buckling at the lower section of the turbine doorway was identified as the primary failure mode. Under near‐fault ground motions, dynamic buckling is primarily governed by geometric nonlinearity, whereas buckling induced by far‐fault ground motions predominantly influenced by both plastic deformation and geometric nonlinearity. Pulse‐like ground motions demonstrate a higher propensity to induce dynamic buckling compared to non‐pulse‐like ground motions. At a 90% reliability level for elastoplastic deformation capacity, the ductility factors are 7.41, 9.48, and 3.80 for near‐fault pulse‐like, near‐fault non‐pulse‐like, and far‐fault ground motions, respectively.