Buildings that Use Base Isolation Technology
Q: How many structures in the United States currently use base isolation technologies?
A: According to the NEHRP Recommended Provisions for Seismic Regulations for New Buildings and Other Structures, Part 2: Commentary (FEMA 450-2/2003 edition), "The potential advantages of seismic isolation and the recent advancements in isolation-system products already have led to the design and construction of over 200 seismically isolated buildings and bridges in the United States."
The 5 structures listed below employ base isolation technologies, either as the original construction or a retrofit.
- Utah State Capitol, Salt Lake City
- Standing in an earthquake zone where seismic monitoring stations record more than 700 earthquakes each year, the historic Utah State Capitol has undergone a complete preservation and base isolation retrofit. The capitol is a monumental, four-story, reinforced concrete building with granite cladding and a large copper-clad concrete dome. The base isolation system consists of 265 isolators, each weighing 5,000 pounds.
- Utah State Capitol Seismic Retrofit and Restoration
- Foothill Communities Law & Justice Center, County of San Bernardino, California
- This 4-story structure situated 12 miles from the San Andreas fault in Rancho Cucamonga, CA, was the first building in the U.S. to have an innovative earthquake-resistant design to withstand a magnitude 8.3 earthquake. It has a full basement and a sub-basement for its base isolation system, consisting of 98 isolators of multi-layered natural rubber bearings reinforced with steel plates.
- Foothill Communities Law & Justice Center
- Los Angeles County Fire Command & Control Facility, California
- The same high-damping rubber system used for the Foothill Center was also adopted for the Fire Department Command and Control Facility (FCCF) of Los Angeles County, completed in 1990.
- L.A. Fire Department
- Los Angeles County Emergency Operations Center, California
- The EOC is a 2-story steel braced frame structure isolated using 28 high-damping natural rubber bearings provided by the Bridgestone Engineered Products Company.
- Caltrans Traffic Management Center, Kearney Mesa, California
- The Caltrans new, 2-story 40,000 sq. ft steel frame building uses 40 high-damping rubber bearings provided by the Bridgestone Industrial Rubber Products, (USA), Inc.
- Caltrans Traffic Management Center
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