A) Passive Systems
Passive damping systems can be divided further into two sub-categories:
– Energy-dissipating-material-based damping systems such as viscous dampers and viscous-elastic dampers
–
Auxiliary mass systems to generate counteracting inertia forces such as
Tuned Mass Dampers (TMD) and Tuned Liquid Dampers (TLD).
B) Active Systems
An active structural control system is
the one that has the ability to determine the present state of the
structure, decide on a set of actions that will change this state to a
more desirable one, and carry out these actions in a controlled manner
and in a short period time. While some passive systems, such as
TMDs
or TSDs, are effective only for a narrow range of loading conditions,
active systems can perform effectively over a much wider range and they
are a more advanced form of functional performance-driven technologies
in architecture. Examples are active mass dampers (AMD) and active
variable stiffness devices (AVSD). The AMDs resemble the TMDs in
appearance, although the vibration of a building is picked up by a
sensor, the optimum vibration control power calculated by a computer,
and the movement of the building is reduced by shifting a moveable mass
with an actuator. The AVSDs continuously alter the building’s stiffness
to keep the frequency of the building away from that of external forces,
such as earthquakes, to avoid a resonance condition. Although their
cost-intensiveness and reliability issues are limiting the use of active
systems at present, with more research, they would have great potential
for future applications.
CONCLUSION
Among
various types of structures for tall buildings, Diagrid is the one
which has many advantages such as: aesthetic, structural performance,
material saving potential, freedom of space arrangement thanks to the
lack of structural columns, etc. Diagrid is becoming the predominant
choice for
high-rise projects. Keeping in mind these features,
this paper summarises the strategies to mitigate lateral forces which
are suitable for high-rise Diagrid buildings, but also applicable to
other types of structures. The strategies range from architectural
design techniques such as modifying building
form, to structural reinforcement tactics, and using damping systems/devices.
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