Dynamic response of cable-stayed bridges with seismic isolation system and eddy current dampers.

A cable-stayed bridge is a structural system consisting of a deck supported by cables anchored to a tower. This type of system is very flexible, allows large spans ranging from 150 to 600 meters, which tower and deck connections may suffer damage in conditions of strong winds and earthquakes. This study evaluates the performance of a seismic isolation system with eddy current dampers (ECD) applied in a cable-stayed bridge. ECD have been recently implemented in suspension bridges. Their main advantage is the lower maintenance and probability of long service life, even so the magnitude of the force developed is still the focus of attention of researchers. This study examines the acceleration and displacement response of a cable-stayed bridge with seismic isolators and ECD dampers. The structural system studied corresponds to a cable-stayed bridge located in Illinois-United States. In the proposal were obtained the dynamic response of three seismic protection systems, conventional, seismic isolators and isolation systems with ECD. The model is developed in two-dimensional using the finite element method through MIDAS CIVIL. A parametric analysis of the seismic protection allowed to identify the effects on the reduction of the dynamic response of the bridge. Finally, some conclusions on the technical feasibility of these systems are listed.