Seismic Design with Fluid Dampers as Part of a Base Isolation System

I'm Doug Taylor of Taylor Devices, Inc., with Professor Michael Constantinou of the State University of New York at Buffalo. Behind us is an isolated highway bridge model, using rubber isolation bearings combined with Fluid Viscous Dampers. This research involves collaboration between the University and industry, a process that allows promising new technology to be implemented much more quickly than would normally be expected.

We'd like to take you on a quick tour of the new San Bernardino County Medical Center at Colton, California. This project came out of our research collaboration, and uses nearly 200 pieces of a 320,000 lb. output Fluid Viscous Damper.

This is the medical center, with its five buildings and a total floor space of 900,000 square feet. The project is located in a highly seismic area, requiring an exceptional level of protection. All buildings are base isolated on large rubber bearings, with dampers mounted in parallel with the bearings. The overall arrangement is similar to an automobile suspension, except that seismic motion occurs horizontally, rather than vertically. The rubber bearings are the spring elements, the fluid dampers dissipate the seismic energy.

This is one of the dampers with testing completed and ready for painting. The damper is 14 inches in diameter, 12 feet in length, with an available stroke of plus or minus 24 inches. Each damper dissipates some 3,000 horsepower under maximum earthquake conditions.

Here we are at the job site, in the basement area of the main nursing tower. The damper installs between the rigid floor mat of the building and the foundation in the basement.

This is a close-up of the damper end attachment. For ease in installation, a simple pin connection with washers and cotter key is used.

Here's another damper installed. Because of its compact size, Taylor Dampers fit easily into relatively confined spaces.