Stress distribution characteristics of wind turbine foundation and flatness correction based on model test
In order to effectively acquire the complex stress distribution of the wind turbine foundation under the wind load,a correction method for hypothesis of foundation stress plane distribution was put forward.The principle of similarity was used as the theoretical basis to establish a scaled physical model system of the foundation of wind turbines in mountainous areas.Horizontal wind loads with different mean wind speeds and time steps of fluctuating wind were simulated.The foundation static and dynamic pressure under different working conditions was tested,and the distribution mode and evolution law of the foundation pressure were studied.A flatness correction method for foundation stress was proposed.The results show that the foundation pressure increases with the increase of the wind speed.When the wind speed is constant,the pressure difference increases with the increase of the time step,which means that low frequency pulsating wind can more likely threaten foundation stability.The dynamic pressure is only 1/20-1/12 of the static pressure,and the pseudo-static method can be used to calculate the stress state of foundation.If the calculation method of foundation stress in common building codes is used,the difference of foundation stress will be underestimated and the result will be unsafe.However,after the flatness correction,the corrected stress value is closer to the measured stress value,which validates the rationality of flatness correction,and also means that the design depth of the foundation can be greater.Therefore,the flatness correction method provides a new idea for the safety design of the foundation of mountain wind turbine.
万方数据
维普
