Composed Isolation System Concept for Vibration Effects Mitigation on Bridge Structures

A bridge structure represents an important infrastructure component capable of withstanding considerable efforts from traffic, wind, or seismic actions. To meet the stability requirements, these structures are designed to cope with the most unfavorable static and dynamic loading situations. At present, isolation solutions are available for these structures types by adding auxiliary mechanical systems to the bridge structure base so that the structure’s response is modified when considerable external forces requesting the resistance structure occur. These systems are considered as isolation, and energy dissipation devices being increasingly used in building practice at present. In this paper, a composed isolation system is presented that combines the insulator role of pendulum sliding bearing with the dissipation role of viscous fluid systems. For better isolation results of the composed system, elastomeric elements have been added to the base of the sliding bearing so that these elements have the ability to attenuate vibrations from different dynamic actions. There are presented modeling elements and results of numerical analyzes made for the pendulum sliding isolating system model. By combining the action of the composite system elements, a complete insulation of a bridge structure can be achieved against the effects of intense and varied vibratory actions having advantage over the use of a single type of protective system meant to isolate the bridge structure.