Research On Aerodynamic Measures Of The Wind Sensitive Structures

The wind sensitive structures, including super-tall building, long-span roof and long-span bridge, have the characteristics of light wight, flexible stiffness, small damping and low natural frequecy, and the wind load has been becoming the main controlling load in their structure design. Reducing the wind load and wind-induced responses of structures becomes one of the most important reseach fields of the wind engineering. According to aerodynamics, the wind load is closely related to the shape of the structures. Simultaneously, aerodynamic measures, i.e. changing building shape or surrounding, setting the guiding devices, are known as the most economical ways to improve wind resisting behaviors of the wind senstive structures.The proposed research focuses on aerodynamic measures of the wind sensitive structures to improve their wind resisting behaviors. Wind tunnel tests and the numerical simulations had been carried out to investigate the characteristics of wind load on these structures. Moreover, aerodynamic measures of the wind sensitive structures were investigated by changing the building shape or surrounding, setting guiding devices to improve their wind resisting behaviors. Details are following.(1) Super-tall building:Decreasing the cross-sections of super-tall building along the height is an effective method of aerodynamic measures. Based on the wind tunnel test, the influence of tapering ratio on the super-tall building was determined in frequency domain. Then, mathematical model of wind force of super-tall building with different tapering ratio was given through least square fitting method. Comparing with other empirical models, the given model was proved to be more suitable for the super-tall building with tapering.(2) Long-span roof:Wind tunnel test and numerical simulation was carried out to investigate wind load distribution of the typical long-span cantilevered roof. Results show that the provided numerical model can simulate the complex flow around long-span roof. Basing on the proposed model, the influence of roof angle and ancillary building on the wind load distribution of the long-span roof, in the view of aerodynamic measures, was carried out to improve its wind resisting behavior.(3) Long-span bridge:Two-dimensional numerical model of the main girder of typical long-span self-anchored suspension bridge was established. Comparing with the test results, the model can simulate the complex flow around girder. Based on the numerical model, three-component coefficient of the girder was studied. Then the influence of the stabilizing barrier and turning plate on three-component coefficient was investigated to improve its wind resisting behavior.