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V. Iancu and L. Cindea
method involves a much higher initial cost. Some of the major advantages of the base
insulation system are to ensure the continuous operations of the construction and to
limit the maintenance works at the level of the seismic insulators [3].
The use of friction pendulum for the seismic isolation of constructions provides
greater stability to earthquakes than conventional protective solutions [4]. They have
very good performance characteristics compared to other types of seismic insulators,
and they have a high fatigue strength and are characterized by slipping combined
with the return force.
Due to their rectangular hysteresis loop, which most of these insulators present,
it leads to the conclusion that they have a behavior similar to the Columbian-type
friction.
2 The Working Model of the Friction Pendulum Isolator
In the paper is presented a block with 5 floors seismically isolated by means of
friction pendulums, Fig. 1. The building is supposed to be located in Banat, known
as a seismic area with earthquakes of magnitudes between 3 and 5 Richter degrees
but not exceeding 5.6° Fig. 2.
In operation, the friction pendulum exhibits a low displacement, and their behavior
is characterized by rigidity and strength. As shown in relation (1), the rigidity of the
system is totally dependent on axial force G and radius of curvature R.
k =
G
R
(1)
Fig. 1 Geometry and working mode of the friction pendulum
V. Iancu and L. Cindea
method involves a much higher initial cost. Some of the major advantages of the base
insulation system are to ensure the continuous operations of the construction and to
limit the maintenance works at the level of the seismic insulators [3].
The use of friction pendulum for the seismic isolation of constructions provides
greater stability to earthquakes than conventional protective solutions [4]. They have
very good performance characteristics compared to other types of seismic insulators,
and they have a high fatigue strength and are characterized by slipping combined
with the return force.
Due to their rectangular hysteresis loop, which most of these insulators present,
it leads to the conclusion that they have a behavior similar to the Columbian-type
friction.
2 The Working Model of the Friction Pendulum Isolator
In the paper is presented a block with 5 floors seismically isolated by means of
friction pendulums, Fig. 1. The building is supposed to be located in Banat, known
as a seismic area with earthquakes of magnitudes between 3 and 5 Richter degrees
but not exceeding 5.6° Fig. 2.
In operation, the friction pendulum exhibits a low displacement, and their behavior
is characterized by rigidity and strength. As shown in relation (1), the rigidity of the
system is totally dependent on axial force G and radius of curvature R.
k =
G
R
(1)
Fig. 1 Geometry and working mode of the friction pendulum