Specifications

Base isolators consist of a laminated rubber and steel bearing with steel flange plates for mounting to the structure.

Isolator Function
The rubber in the isolator acts as a spring. It is very soft laterally but very stiff
vertically. The high vertical stiffness is achieved by having thin layers of rubber
reinforced by steel shims. These two characteristics allow the isolator to move
laterally with relatively low stiffness yet carry significant axial load due to their high
vertical stiffness. The lead core provides damping by deforming plastically when the
isolator moves laterally in an earthquake.

Size Ranges
Isolators from 12 to 60 inches in diameter with capacities of up to 4,000 tons are
manufactured. Custom dimensions are available for special applications.