Seismic Retrofitting

Specializing in seismic upgrades of existing and historical structures

Seismic Retrofitting Bay Area

Seismic base isolation is a relatively new seismic retrofitting technique that provides a structure flexibility to withstand the lateral forces during an earthquake. Base isolators act like large “motor mounts” when placed under a load-bearing column of a bridge or building and, during a seismic event, the isolators absorb the impact thereby greatly reducing the seismic forces transmitted through the building.

Sheedy Crane has been instrumental on a number of key seismic retrofitting projects to include San Francisco’s City Hall, the largest structure in the world ever upgraded with seismic base isolators. Sheedy also installed the largest friction-pendulum isolators at the time on the Benicia-Martinez Bridge.

In fact, many of the concepts for temporary shoring column load transfer and seismic dampening equipment installation are unique to Sheedy, such as our specially designed friction griping technique.

What Sheedy can do for you:
  • Complete column base isolator, slider, and flat-jack installation services
  • Column isolation, temporary support, jacking system installation, and load transfer engineering
  • Complete project management and engineering services performed directly by Sheedy Drayage Co. personnel.

List of major projects:
  • Pasadena City Hall
  • Pasadena, CA
  • Project completed in April 2007
  • 238 friction-pendulum isolators installed Column loads up to 450 tons
  • Oakland City Hall
  • Oakland, CA
  • Project complete in November 1994
  • 113 isolators installed Column loads up to 1,900 tons
  • Veterans Administration Medical Center
  • Long Beach, CA
  • Project complete in November 1994
  • 113 isolators installed Column loads up to 1,900 tons
  • Kerckhoff Hall, U.C.L.A
  • Los Angeles, CA
  • Project completed in December 1995
  • 128 isolators and 36 sliders Column loads up to 281 tons


  • San Francisco City Hall
  • San Francisco, CA
  • Project completed in August 1997
  • 530 isolators and 61 sliders installed Multiple column loads up to 2500 tons total
  • Benicia-Martinez Bridge
  • Martinez, CA
  • Project completed in June 2001
  • 22 friction-pendulum isolators installed Column loads in excess of 3,500 tons
  • Asian Art Museum
  • San Francisco, CA
  • Project completed in May 2002
  • 196 rubberized isolators installed Column loads up to 600 tons
415-648-7171