1. Friction Damper with Coned disc springs August, 2001 Obayashi Corporation

2. Laminated Rubber Bearing Natural Rubber Bearing Lead Rubber Bearing High Damping Rubber Bearing Lead plug

3. Damper Selection Line-up Steel damper Oil damper Lead damper Friction damper with Coned disc springs

4. Feature of Dampers ① Steel damper Δ Energy Absorption Δ Stroke limit Δ Directional operation X Load Support ③ Oil damper ○ Energy Absorption Δ Stroke limit X Directional operation (one direction) X Load Support ② Lead damper Δ Energy Absorption Δ Stroke limit Δ Directional operation X Load Support ④ Friction damper with Coned disc springs ○ Energy Absorption Δ Stroke limit ○ Directional operation ○ Load Support

5. 2b=  190 h=14.7 2a=  420 Unit/mm t=11.0

6. Sectional plan of Coned disc spring 051015 0 5 10 15 20 [ I ] [III] [ I ] [ II ] [III] Vertical Displacement (mm) Vertical load (tonf) [ II ] Test Analysis FEM

7. Single DiscTwo columns of single disc Double DiscsTwo columns of double discs 40 10 20 30 40 10 20 30 40 10 20 30 40 10 20 30 0 0 0 401020300 0 401020300 401020300 401020300 [mm] [tonf] [mm]

8. 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

9.  560  400 Unit / mm 460 Height of Coned disc springs/ 240 Inner Guide Coned disc springs Sliding material Stainless Steel Plate

10. Movement W : Weight F : Friction force Friction force F=  W  : Frictional coefficient Superstructure Rubber bearing Foundation Resilient force N Horizontal Friction Force F Stainless steel plate Compress the multiple coned disc springs to occur resilient force Resilient force N Coned disc springs Sliding plate (UHMWP) 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 Friction force

11. Go-down : a Initial height Linear spring Nonlinear coned disc springs Resilient force N1 Resilient force n1 Up-lift : b Resilient force n2 Resilient force N2 Nonlinear coned disc springs Linear spring [Linear spring] Resilient force [Nonlinear coned disc springs] Vertical displacement 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 n2 N1 N2 ab ab 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 Resilient force Vertical displacement Initial height

12. Normal timeEmergent excessive earthquake Weight 100% Support 75% Support 10% Support 25% Support 90% Foundation Superstructure Stainless steel plate In normal time, most of superstructure weight is supported by rubber bearing (ex. 75%) In emergent excessive earthquake, rubber bearing will have large horizontal displacement and cannot support superstructure, then the friction damper takes support it ins Rubber bearing Weight 100% Foundation Superstructure

13. 0.4 0.2 0 -0.2 -0.4 0.4 0.2 0 -0.2 -0.4 -40-30-20-10010203040 -200-150-100-50050100150200 Frictional coefficient Horizontal displacement (mm) [For Wind Load] [For EQ Load] Frictional coefficient Horizontal displacement (mm)

14. 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) Multi Function for the friction damper with coned disc springs

15. New Base Isolation Building The new base-isolation building in Nagoya Friction damper with coned disc springs Oil Damper

16. The new base-isolation building in Nagoya Elevation Plan Oil damper Friction damper with coned disc springs Rubber bearing Friction damper with coned disc springs Oil damper

17. 010 20304050607080 10 0 5 15 20 30 25 35 40 Available zone -200-150-100-50050100150200 12 8 0 4 -4 -8 -12 Stainless steel plate Multiple coned disc springs Sliding Plate Inner Guide Outline of the friction damper with coned disc springs Vertical load-deflection curves Horizontal hysteresis loops Friction force (tonf) Vertical force (tonf) Vertical displacement (mm) Horizontal displacement (mm)

18. 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