MODAL COUPLING EFFECTS FOR WIND-INDUCED RESONANT RESPONSE OF LARGE-SPAN ROOF STRUCTURES

A method to judge the magnitude of resonant response modal coupling effects is proposed in this paper. It considers systematically the dynamic characteristics of the structure as well as the characteristics of wind load, and then the resonant response modal coupling coefficient is defined. Based on this coefficient, a few parameters with respect to fluctuating wind loads and structural modes are sufficient to estimate the magnitude of resonant response modal coupling effects, and then the dominant-coupling modes of resonant response are determined. On this basis, a practical method to combine resonant response is obtained, which considers the modal coupling effects availably. Finally, the effectiveness of the proposed method is verified by the analysis of wind-induced vibration response of Beijing National Stadium.