Fully coupled buffeting analysis of long-span cable-supported bridges: Formulation

A formulation for fully coupled buffeting analysis of long-span cable-suppo rted bridges is presented, in which dynamic coupling between modes of vibra tion, dynamic forces on bridge deck and towers and cables, and varying wind speed and structural properties along the bridge deck and towers and cable s can be: taken into consideration. This formulation adopts a. finite eleme nt approach and a pseudo-excitation method. Aeroelastic forces on the bridg e deck are changed into nodal forces to form aeroelastic damping and stiffn ess matrices while aerodynamic forces on the bridge deck, towers and cables are converted into nodal forces to obtain a loading vector. After the syst em equation of motion is assembled, the pseudo-excitation method is applied and the formulation is programmed so that a personal computer can be used to execute the buffeting analysis of the system of hundreds of degrees of f reedom in 1 or 2 h. The results from the case study of a long suspension br idge using the proposed formulation and program are also selectively presen ted in this paper. (C) 1999 Academic Press.