About the Forces and Moments
that Influence the Behavior of a Friction
Pendulum
Vasile Iancu and Lenuta Cindea
Abstract The paper presents the geometry of a seismic insulator, the friction
pendulum, used in the seismic isolation of a 5 floors apartment building, which
also has a technical basement, between the infrastructure and the foundation, where
the seismic insulators will be mounted. Being built in the Banat area, the block has
been designed with a Class III Reinforced Concrete Structure. It is known that in this
area, the earthquakes happen close to the surface and have a magnitude between 3
and 5.7 on the Richter scale. These earthquakes are followed by replicas that extend
over the period of several months. As a result of these earth movements, buildings
are subjected to certain forces and moments that put them at risk of degradation or
even demolition. Considering these inconveniences, we want to improve the dynamic
behavior of buildings in the Banat area by decoupling the foundation from the infrastructure. Taking into account the forces and moments acting on it, knowing the value
of the ground acceleration for the design, a g = 0.20 g for IMR = 225 years and the
value of the control period (corner) T C = 0.7 for Resita, the solution chosen for the
isolation of the building against earthquakes was the seismic friction pendulum with
a single sliding surface.
1 Introduction
The protection against seismic activities has been a preoccupation since ancient times
and is the main objective of seismic engineering. Seismic protection of buildings
can be done either by designing the structure so that it has sufficient resistance, by
introducing special structural devices into the structure of resistance [1].
The method of isolating the base of the structure involves the interposition between
the infrastructure and the superstructure of seismic isolators to decouple the movement of the structure from the ground motion [2]. So during an important seismic
event, there is no degradation of the structural and non-structural elements, but this
V. Iancu (B) · L. Cindea
Eftimie Murgu University, Traian Vuia Square, Resita, Romania
e-mail: v.iancu@uem.ro
© Springer Nature Switzerland AG 2021
N. Herisanu and V. Marinca (eds.), Acoustics and Vibration of Mechanical
Structures—AVMS 2019, Springer Proceedings in Physics 251,
https://doi.org/10.1007/978-3-030-54136-1_52
515
that Influence the Behavior of a Friction
Pendulum
Vasile Iancu and Lenuta Cindea
Abstract The paper presents the geometry of a seismic insulator, the friction
pendulum, used in the seismic isolation of a 5 floors apartment building, which
also has a technical basement, between the infrastructure and the foundation, where
the seismic insulators will be mounted. Being built in the Banat area, the block has
been designed with a Class III Reinforced Concrete Structure. It is known that in this
area, the earthquakes happen close to the surface and have a magnitude between 3
and 5.7 on the Richter scale. These earthquakes are followed by replicas that extend
over the period of several months. As a result of these earth movements, buildings
are subjected to certain forces and moments that put them at risk of degradation or
even demolition. Considering these inconveniences, we want to improve the dynamic
behavior of buildings in the Banat area by decoupling the foundation from the infrastructure. Taking into account the forces and moments acting on it, knowing the value
of the ground acceleration for the design, a g = 0.20 g for IMR = 225 years and the
value of the control period (corner) T C = 0.7 for Resita, the solution chosen for the
isolation of the building against earthquakes was the seismic friction pendulum with
a single sliding surface.
1 Introduction
The protection against seismic activities has been a preoccupation since ancient times
and is the main objective of seismic engineering. Seismic protection of buildings
can be done either by designing the structure so that it has sufficient resistance, by
introducing special structural devices into the structure of resistance [1].
The method of isolating the base of the structure involves the interposition between
the infrastructure and the superstructure of seismic isolators to decouple the movement of the structure from the ground motion [2]. So during an important seismic
event, there is no degradation of the structural and non-structural elements, but this
V. Iancu (B) · L. Cindea
Eftimie Murgu University, Traian Vuia Square, Resita, Romania
e-mail: v.iancu@uem.ro
© Springer Nature Switzerland AG 2021
N. Herisanu and V. Marinca (eds.), Acoustics and Vibration of Mechanical
Structures—AVMS 2019, Springer Proceedings in Physics 251,
https://doi.org/10.1007/978-3-030-54136-1_52
515