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Oakland City Hall was the first-ever high rise seismic retrofit using seismic base isolation.
Customized Solution
- Forell | Elsesser designed the seismic retrofit for this 160,000 s.f. 18-story historic City Hall building constructed in 1913. The structure was damaged in the 1989 Loma Prieta earthquake.
- Base isolation was used at the base, with a combination of concrete shear walls and braced frames above.
- The project required the transfer of large column loads of 4 million pounds onto the seismic isolator bearings.
- The seismic retrofit elements are completely hidden within the existing historic envelope.
Highlights
- Architect: VBN Architects/Michael Willis Architects
- Owner: City of Oakland
- Base isolated historic seismic retrofit, including 113 isolators
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Team
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Mason Walters
Senior Principal
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Paul Rodler
Senior Principal