Experimental Study On Wind Induced Response And Aero-elastic Effects Of Guangzhou West Tower

Modern super tall buildings are usually constructed with innovative structural systems and high strength materials; tend to be more flexible and lightly damped than those in the past. As a consequence, the sensitivity of these buildings to strong wind has increased. Wind load plays the key role in the structural design of those buildings.Massive experiments indicate that wind induced response on super tall buildings in the crosswind direction may be more significant than that in the along-wind direction. For high flexible buildings, the effect of the interaction between the structure and wind on wind induced response and wind loads may also significant. Aerodynamic damping that reflects the effect of the structure-wind interaction often plays an important role in estimations of wind induced dynamic responses of super high-rise buildings. Aero-elastic model test is considered to be the most reliable method for evaluating wind effects on super tall buildings.Guangzhou West Tower (GWT) with a height of 432m is at present the tallest building in south China. In first part of this study, in order to evaluate the aeroelastic effect, an experiment of GWT is firstly carried out using the MDOF aero-elastic model technique in boundary layer wind tunnel. and the results are compared with those of stiffness model based experiment using the high frequency base balance (HFBB) technique. The Random Decrement Technology (RDT) is applied to identify the aerodynamic damping of GWT. Good agreement in wind-induced response is found between the two techniques when same damping ratio is used to calculate the wind induced response in the HFBB approach. Generally, the aerodynamic damping of GWT is positive at large scope of wind speed. The results show that the aerodynamic damping increase with the increase of the wind speed and a maximum aerodynamic damping of 1.74% is found when the wind speed at the gradient wind height is 45.4m/s. Then the aerodynamic damping decrease rapidly near the critical wind speed, and finally a minimum aerodynamic damping of–0.06% is found at wind speed of 51m/s.In part 2, a tuned mass damper (TMD) is applied to reduce the wind-induced vibration of GWT. Wind tunnel experiments are performed to verify the effectiveness of TMD on reducing the wind-induced vibration on super tall building model. The effects of the introduction of a TMD on the vibration of the building model of GWT are analyzed and discussed.Finally, some conclusions are summarized as the reference for the wind-resistant design of GWT.