BE95-1258 Highly Adaptible Rubber Isolation System

Rubber based devices employed in base isolation have been used in bridge engineering for over 40 years. The limited damping capacity reduces the field of application when dynamic excitation becomes critical. This project focuses primarily on bridges and viaduct structures but with extensibility to buildings compromising new design and retrofitting.

The research project is aimed at developing abilities to control the dissipation capacity of rubber devices. The importance of adaptability is observed through the definition of measures and elements for a rubber isolation system supported by design rules, which can be applied to different site conditions. The result will provide an inexpensive isolation system considering implementation and maintenance costs.

The investigation in new design of rubber devices will result in high energy dissipation in the range of 15% to 30% equivalent damping. Through probabilistic methods, parameters and properties will be quantified in terms of reliability of the isolation system and therefore, in consequence, an optimized solution strategy is possible. Sophisticated software will be developed enabling the analysis of the rather complicated mechanical model. A shaking table test will give especially important feedback of the installed rubber isolation system under real conditions. Important hot spots in terms of quality for production will be identified as well as sensitivities for implementation accuracy will be quantified.