This paper proposes an active scheme for vibration control of cable-stayed bridges under seismic loads. The control action is supplied by using a subset of the stay cables as active tendons. The dynamic model of the bridge is decomposed into two coupled subsystems, one of them including the degrees of freedom that are directly influenced by the active tendons. A linear control law is proposed to drive the active tendons via feedback of the states of these degrees of freedom only. A stability analysis gives conditions to ensure the existence of a ball of ultimate boundedness for the whole bridge model in the presence of a class of uncertainties in the model parameters and the seismic excitation. The effectiveness of the control scheme is shown numerically on a finite element model of a pedestrian cable-stayed bridge
A nonlinear decentralized active tendon controller that substantially reduces the magnitude of the vibrations of a segment of a cable-stayed bridge induced by a seismic excitation is presented in this paper. The model used to represent the dynamic behaviour of the bridge takes into account the inherent nonlinearities due to the stay cables geometry. This is in contrast with traditional models used by previous designers of active controllers of cable-stayed bridges, who assumed completely linear models. The proposed controller is comprised of a linear and a nonlinear part. Its performance is verified via digital computer simulation.