Study On Aerodynamic Damping Of The Concrete Solar Tower Based On Aeroelastic Wind Tunnel Tests

The high-rise building,including television tower,communication tower and endothermic tower has the characteristic of high slender ratio and flexibility and low damping.With the attack of wind,resonance in the cross-wind direction is easy to be intrigued by the vortex-induced vibration(VIV).In order to acquire the response especially the VIV amplitude,it is fundamental to accurately estimate the wind load and damping,which is the most important and uncertain parameter affecting the response.Based on the one concrete solar tower,aerodynamic damping is identified with the aid of the already existed aero-elastic model,results of which can be used as the reference knowledge for the parameter selection of calculation of the wind induced reaction,vibration mitigation and modeling simulation.The content mainly focuses on the following aspects:(1)The random decrement technique(RDT)and stochastic subspace identification(SSI),mainly the data driven stochastic subspace identification(SSI-DATA)are illustrated.(2)The basic principle of the MDOF aero-elastic model is introduced,including the design of similarity parameters and model making process.(3)Before the formal test,a trial step is taken to verify the reliability of RDT and SSI-DATA by comparison with the identification of extended Kalman filter(EKF).And the wind tunnel test is launched on the already existed aero-elastic model.The aeroelastic damping in along wind and cross wind direction is obtained via RDT and SSI respectively,showing us the trend of the aero-elastic damping with the change of the reduced velocity.By pasting the adhesive tape,we can get 4 different structural dampings,whose influence on the aero-elastic damping is also studied.At the same time,the amplitude-dependent damping is researched.Then the effect of vibration mitigation has been analyzed after processing the tip acceleration and bottom force.(4)In the end,the anharmonicity of VIV is explained by establishing a probabilistic model whereby the occurrence probability of the VIV resonance can be conveniently computed.