Retrofitting Methods for Existing Ring Foundations of Onshore Wind Turbines under Seismic Loading: Anchor Bolt Strengthening and Ring Beam Jacketing

To address the issue of retrofitting existing foundations following the replacement with higher-capacity wind turbines (including the tower and the RNA), this study proposes a foundation retrofitting method involving the addition of anchor bolts and the enlargement of the ring beam. To validate the effectiveness of the retrofitting method, ABAQUS finite element software was used to develop three wind turbine-foundation-soil finite element models. A comparative analysis of the dynamic responses of the three models was conducted under the same seismic load. The study shows that the foundation retrofitting method can significantly improve the seismic performance of the wind turbine foundation.