Base isolation

Main page: Earthquake engineering

Shake-table testing of two building models at CSUN. The right one is equipped with a base isolation device.

Base isolation is a collection of a building’s units resting on its foundation to provide separation of the building from shaking ground thus improving seismic performance.

Basic parts of base isolation system

Base isolation system consists of isolation units with or without isolation components, where:

1. Isolation units are the basic elements of base isolation system which provide the mentioned separation effect to a building structure.

2. Isolation components are the connections between isolation units and other parts of the building having no separation effect of their own.

Famous base-isolated buildings

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  Pasadena City Hall, California

• 

  San Francisco City Hall, California

• 

  Salt Lake City and County Building, Utah

History

From the very beginning, the theory of base isolation rested on two pillars: heavy damping and frequency separation. Unfortunately, nobody paid any attention that the heavy damping was a sort of a strong connection between a substructure and superstructure, and that the idea of decoupling them with the help of such connections was of no good. Anyway, to virtually test-drive any design concept of base isolation, some online help is available now.