Geotechnical Design of Onshore Wind Turbine Foundations: Some Applications and Lessons Learned in Vietnam

This paper first summarizes essential standards, guidelines, and criteria for design of wind turbine generator (WTG) foundations, focusing on onshore projects. The paper then briefly describes four main steps in geotechnical design of a WTG foundation, including geological investigation, preliminary foundation design solution, geotechnical design, and structural design. This paper then presents some lessons learned from the foundation design and construction of five wind farm projects in different ground conditions in Vietnam. They include the importance of raked piles to improve the stiffness of foundation, ultimate bearing capacity of piles not affected by negative skin friction, and the proper consideration of maximum possible groundwater level to ensure the bearing capacity of shallow foundations.