Abstract
This paper investigated the possibility of designing a shape for aerodynamic vibration control of a building using several different characteristics of aerodynamic instability of different shapes for each wind direction. Experiments were conducted using different characteristics, especially for galloping and vortex induced vibration, on a square prism with and without comer recessions. The differential is as the galloping occurs at the square prism when wind acts normal to the prism, and vortex induced vibration with great response displacements occurs at the square prism with comer recessions when wind acts aslant to the model. On the other hands, relationships between with aerodynamic instability and wind force were investigated with part of the wind force on several levels of models. Then, it is clarified that wind force which act on the upper part of the square prism greatly influences the occurrence of galloping when wind acts normal to the model. And it is also clarified that the middle part of the layers of square model with the comer recessions greatly influences vortex induced vibration when wind acts aslant to the model. Therefore, a model as a combined of them are proposed to control the aerodynamic instability, taking account of those parts of the wind force on each layer against wind actions. The proposed model has square in the low 5/8 and square with the comer recessions in the upper 3/8 of it. Thus, great response displacements caused with aerodynamic instability can be prevented or reduced in all wind directions.
