Response of a wind turbine subjected to near-fault excitation and comparison with the Greek Aseismic Code provisions

The paper focuses on the study of the dynamic response of a wind turbine installed close to seismic fault in an earthquake prone region of Greece. The investigation of the seismic behavior of the turbine is performed with response spectrum analysis using the elastic acceleration spectrum provided by the Greek National Aseismic Code for the project area, increased by 25% due to proximity to seismic fault, as recommended by the Code. Also, dynamic analysis is performed using the spectrum obtained from the assessment of seismic hazard at the site of the project (Local), for two typical cases of earthquakes of magnitudes Ms=5.8 and Ms=7.3 with epicentral distances of 1 km and 11 km from the test position, respectively. Finally, a time-history analysis is carried out using an artificial accelerogram obtained from the local spectrum envelope, for the site of the project, considering 1% damping ratio. The direct comparison of the response spectrum analysis results with the corresponding ones obtained from the dynamic and time-history analyses indicates that the implementation of the elastic acceleration spectrum is insufficient, although increased, and therefore it could be deduced that the current recommendation of the Greek National Aseismic Code to consider an increment of 25% on the elastic acceleration spectrum in regions close to seismic faults, requires review and further improvement.

► The response of a wind turbine on seismic fault area was investigated. ► The influence of the soil-foundation interaction was considered. ► The earthquake response of the wind turbine was captured with spectrum analysis. ► Also, dynamic analysis was performed for two typical cases of earthquakes.