Study on defect analysis and grouting reinforcement of onshore wind turbine foundation

Combined with a wind turbine project in Southwest China, the damage characteristic of the wind turbine foundation was studied by the concrete plastic damage model. The range of gap-inanition defect was determined by the survey data, and the impact of defect on the foundation security was analyzed. The selection of grouting materials in the grouting reinforcement were discussed, and the influence of the grouting materials' elastic modulus on the grouting reinforcement was considered. Analysis results show that the crack area of the foundation is concentrated near the upper row of perforated rebar and the bottom flange of the metal ring;the gap-inanition defect will significantly increase the tilt rate of the metal ring, the stress of perforated rebar and the circumferential expansion range of the cracked area;the grouting reinforcement can effectively reduce the stress of the perforated rebar, the volume of the cracked concrete and the tilt rate of the metal ring. The stress of the lower row of perforated rebar will increase as the grouting materials' elastic modulus increases, and the chemical grouting materials with an elastic modulus in the range of 1 to 6 GPa is recommended in the project. © 2021, Editorial Board of Journal of Huazhong University of Science and Technology. All right reserved.