Wind power structures（WPS）are prone to overturn and buckling under seismic load.If wind load is applied simultaneously

the risk of structural failure increases.A 1.5MW WPS consisting of wind turbine

tower and pile foundation in coastal area of China is modelled by finite element method using APDL in ANSYS.Natural vibration characteristics and seismic responses of WPS are calculated under different liquefaction degrees of soil site through stiffness reduction of single pile.Observed seismic waves and wind speed history simulated by auto-regressive method are employed to calculate the structural dynamic responses.Results show that the horizontal displacement of wheel hub and the axial force of unfavorable piles increase with the degree of liquefaction.And the stress of the tower bottom reaches the maximum under medium liquefaction.Taking the wind load into account

the horizontal displacement of the hub

the tower bottom stress and the axial force of the most unfavorable piles significantly increase

especially for the stress of the tower bottom and the axial force of the most unfavorable pile at the leeward.