Friction Damper with Coned disc springs

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Friction Damper with Coned disc springs

• August, 2001
• Obayashi Corporation

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Laminated Rubber Bearing
Lead plug
Lead Rubber Bearing
Natural Rubber Bearing
High Damping Rubber Bearing
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Damper Selection Line-up
Oil damper
Steel damper
Friction damper with Coned disc springs
Lead damper
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Feature of Dampers
? Steel damper ? Energy Absorption ? Stroke
limit ? Directional operation X Load Support
? Oil damper ? Energy Absorption ? Stroke limit
X Directional operation (one direction) X Load
Support
? Lead damper ? Energy Absorption ? Stroke limit
? Directional operation X Load Support
? Friction damper with Coned disc springs ?
Energy Absorption ? Stroke limit ? Directional
operation ? Load Support
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Outline of Coned Disc Spring
2b?190
t11.0
h14.7
2a?420
Unit/mm
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III
II
Vertical load (tonf)
Test Analysis FEM
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Sectional plan of Coned disc spring
III
II
I
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Combination of Coned disc springs
Single Disc
Two columns of single disc
40
40
30
30
tonf
tonf
20
20
10
10
0
0
mm
mm
Double Discs
Two columns of double discs
40
40
30
30
tonf
20
tonf
20
10
10
0
0
mm
mm
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Feature of Coned disc spring
Get big Resilient force by compact sized coned
disc spring Linear or nonlinear load-defection
curve can be gained by coned disc spring Get
many kind of load-deflection curve by combination
coned disc springs Use semi-permanently under
allowable stress
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Outline of Friction Damper with Coned disc
springs
?560
Inner Guide
Coned disc springs
Height of Coned disc springs/ 240
460
Sliding material
Stainless Steel Plate
?400
Unit / mm
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Principle of the Friction damper of Coned disc
Springs
Friction force
Movement
W Weight
F Friction force
Friction force F??W ? Frictional
coefficient
Superstructure
Coned disc springs
Resilient force N
Resilient force N
Rubber bearing
Foundation
Horizontal Friction Force F
Compress the multiple coned disc springs to
occur resilient force
Sliding plate (UHMWP)
Stainless steel plate
Horizontal friction force F is occurred when
pressing down the sliding plate(UHMWP) by
multiple coned disc springs resilient force N
against stainless steel plate
F? ? ?N ? Frictional coefficient
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Independence of the height changes of rubber
bearing
In the state of the rubber bearing height becomes
short by low temperature and creep
In the state of the rubber bearing height becomes
high by high temperature
Up-lift b
Go-down a
Resilient force N2
Resilient force n2
Resilient force N1
Resilient force n1
Initial height
Initial height
Linear spring
Nonlinear coned disc springs
Nonlinear coned disc springs
Linear spring
Linear spring
Nonlinear coned disc springs
Resilient force
Resilient force
Resilient variation force of nonlinear coned
disc springs is smaller than that of
linear spring by change of rubber bearing height,
and variation of friction force is so.
n1
N1
n2
N2
Vertical displacement
Vertical displacement
a
b
a
b
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For supporting function of the friction damper
with coned disc springs
Normal time
Emergent excessive earthquake
Weight 100
Weight 100
Superstructure
Superstructure
Support 25
Support 75
Support 10
Rubber bearing
Support 90
Foundation
Foundation
Stainless steel plate
In emergent excessive earthquake, rubber bearing
will have large horizontal displacement and
cannot support superstructure, then the friction
damper takes support it ins
In normal time, most of superstructure weight is
supported by rubber bearing (ex. 75)
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Horizontal hysteresis loops of the Friction
damper with coned disc springs
For Wind Load
Frictional coefficient
Horizontal displacement (mm)
For EQ Load
Frictional coefficient
Horizontal displacement (mm)
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Multi Function for the friction damper with coned
disc springs

• 1. Restrain the movement by strong wind
• (Improvement for dwelling ability)
• 2. Stable damper for earthquake
• (Damper function)
• 3. Support load function
• (Safety device function)

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New Base Isolation Building
Oil Damper
Friction damper with coned disc springs
The new base-isolation building in Nagoya
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The new base-isolation building in Nagoya
Oil damper
Friction damper with coned disc springs
Friction damper with coned disc springs
Oil damper
Rubber bearing
Rubber bearing
Plan
Elevation
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Feature of the friction damper with coned disc
springs
Vertical force (tonf)
Inner Guide
Vertical displacement (mm)
Vertical load-deflection curves
Multiple coned disc springs
Friction force (tonf)
Stainless steel plate
Sliding Plate
Outline of the friction damper with coned
disc springs
Horizontal displacement (mm)
Horizontal hysteresis loops
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Feature of the friction damper with coned disc
springs
Adjust the friction force by the combination
coned disc springs of the friction damper To
operate in all direction, and stroke is limited
by the area of stainless steel plate
Friction force is stable constant Friction
damper can support the load Easy to set the
friction damper with coned disc springs