SHAKING TABLE TEST OF OFFSHORE WIND TURBINE SUPPORTING TOWER

Abstract

At present, the wind power generation technology develops rapidly. As the main supporting structure of the wind turbine, the safety of the tower structure is very important under the action of earthquake. Since the behavior of this kind of tripod structure has not yet been investigated through shaking table test, a 1∶20 scaled model of offshore tripod supporting structure was tested through seismic shaking table. Subjected to a series of seismic ground motions with three peak acceleration levels of 0.3 g, 0.6 g and 0.9 g, the dynamic characteristics of the model structure and the seismic response were studied. Two support condition sceneries of the foundation for the test model were considered: with supports at 1.3 m high of each pile foundation, and removal of the supports (simulated pile foundation failure). Compared with the case with the foundation support, the dynamic acceleration response of the structure after the removal of the support was slightly reduced, and the decrease in the amplitude of peak acceleration in X and Y directions was 9.87% and 5.40%, respectively. In addition, finite element analysis by ABAQUS was performed to analyze the elastoplastic response of the structure, and the simulation results were compared with the test results. Good agreement was observed between the two results, which validates the results of both the finite element analysis and the shaking table test, and provides a reference for the elastoplastic time history analysis of the prototype structure.