Construction Materials | Seismic Isolator for Buildings
The Structure of Seismic Isolating Rubber Bearing
New Structure Technology - "Seismic Base Isolation System", proven during large-scale earth tremors
The Seismic Isolating Rubber Bearing consists of alternating laminations of thin rubber layers and steel plates (shims), bonded together to provide vertical rigidity and horizontal flexibility.
Vertical rigidity assures the isolator will support the weight of the structure, while horizontal flexibility converts destructive horizontal shaking into gentle movement.
Special Characteristics of Bridgestone MRB
- Cover rubber
- the outer cover protects rubber laminations against ultraviolet ray and ozone exposure that deteriorate rubber.
- Bonding
- through a proprietary surface treatment prior to vulcanization, the individual rubber layer and steel shim plate are permanently bonded together between the upper and lower flanges.
Principle of Laminated Rubber Bearing
A standard rubber block can be easily compressed and sheared because of its biaxial softness. A laminated rubber bearing can be easily sheared, but its high vertical stiffness allows it to support a heavy structure such as a building.
| Rubber block | Laminated rubber bearing (LRB) | Comparison of compressive and horizontal shear features |
|---|---|---|
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