Retrofitting the Oakland City Hall

In the aftermath of the Loma Prieta earthquake in 1989, the city of Oakland hired the firm of Forell and Elsesser to devise a system to stabilize the city hall. The key to the design is the base isolation system, which allows the building to remain stable in a severe earthquake.

Details of the base isolation bearings

Schematic of the reinforcements

Model of the reinforcement system, with new structual beams in red