Seismic response analysis of wind turbine towers including soil-structure interaction

In this paper, a multibody model of wind turbine towers with the consideration of soil—structure interaction (SSI) is proposed to investigate their dynamic responses to seismic excitations in time domain. Using joint beam elements, the elastic tower is discretized into many rigid bodies coupled elastically by constraint joints and springs. The SSI is represented by a frequency-independent discrete parameter model approximately. The governing motion equations are derived by the application of Lagrange formalism including Lagrange multipliers. To investigate the effects of SSI and the dynamic behaviour of wind turbine towers under aerodynamic loading and earthquake loading, the tower of a large wind turbine is modelled and simulated with recorded seismic excitations.