Evaluating of Seismically Performance of Cable-stayed Bridge with Seismic Isolation of Friction Pendulum systems

Bridges are among the important structures with considerable performance against seismic loads. The main objective of this study is to evaluate the seismic performance of a cable-stayed bridge which is isolated by Friction Pendulum System (FPS). This research investigated an operating cable-stayed bridge (Karoon4 Oil Pipe Line bridge) in Iran. The nonlinear time history analysis is used to evaluate and compare the results of models with elastomeric bearings (include neoprene) and FPS. Four various far-field earthquake records with different origins, mechanisms, intensity and duration are used for analysis. Plastic hinges are also considered for nonlinear structure behavior in substructures of bridge. Various demands are investigated included the base shear and base moment, deck acceleration, displacement of isolation system, axial force of cables and plastic hinges performance state. In this regard, the base shear and base moment, deck acceleration and axial force of cables are significantly reduced, but the displacement of isolation system is higher than the elastomeric bearings. Furthermore, the Performance states of plastic hinges in isolated substructure are in immediate occupancy level but as-built substructure with elastomeric bearings is in collapse level.

Keywords:

Seismic Isolations , Cable-stayed Bridges , Friction Pendulum System , Non-linear Time History Analysis