Base
isolation,
also known as seismic or base isolation system, is a collection of
structural
elements which should substantially decouple a superstructure from its
substructure resting on a shaking ground thus protecting a building or
non-building
structure's integrity.
Base
isolation is the most powerful tool of the earthquake engineering
pertaining to
the passive structural vibration control technologies. It is meant to
enable a
building or non-building structure to survive a potentially devastating
seismic
impact through a proper initial design or subsequent modifications. In
some
cases, application of base isolation can raise both a structure's
seismic
performance and its seismic sustainability considerably.
Animation
movie 1 : Concept of Base Isolation
(Concurrent
shake table testing
of two building models. The right one is equipped with a seismic base
isolation)
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 are intended to
provide the mentioned decoupling effect to a building or non-building
structure.
2.
Isolation
components are the connections between isolation units and
their parts having
no decoupling effect of their own.
By
their
response to an earthquake impact, all
isolation units may be divided into two
basic categories: shear
units and sliding
units .
