(1. State Key Laboratory of Disaster Reduction in Civil Engineering，Tongji University，Shanghai 200092，China；2. College of Water Resources and Civil Engineering，Northwest Agricultural and Forestry University，Yangling，Shaanxi 712100，China；3. School of Mechanical，Aerospace and Civil Engineering，The University of Manchester，Manchester，M13 9PL，UK；4. Department of Civil Engineering，Renai College of Tianjin University，Tianjin 301636，China)
Abstract：According to the site information of an offshore project of wind turbine，the dynamic characteristics and the seismic response of the supporting system of turbine were analyzed by considering the complicated interactions of water，soil，and supporting system. The fluid-structure coupling，the seepage of saturated soil and the pile-soil contact behaviour were simulated using the finite element method. Four working conditions were considered for the analysis of characteristics of natural vibration，i.e. the single-pile supporting with water and without water in consideration，the four-pile supporting with water and without water in consideration. The results from the simulations indicated that water had negligible influence on the lower-order frequencies of the structure，but led to a large reduction on the high-order frequencies. Water reduced the horizontal and the vertical displacements，the peak acceleration and the effective stress of the supporting system. The excess pore water pressure in the foundation soil fluctuated under seismic actions. The calculated structural displacements and effective stresses met the regulation requirements.
2015, Vol. 34 
