Exploratorium Giant VortexKayseri, Turkey

Maffei Structural Engineering worked with the creative designers of the Exploratorium’s Exhibit & Media Studio to develop and analyze a first-ever seismic application of swing-arm isolation system for this towering museum exhibit. Based on one of the signature exhibits at San Francisco’s Exploratorium, the museum’s Global Studios initiative recently built this record-sized version of the Vortex at the Kayseri Science Center museum in central Turkey.  The exhibit features a slender tower of swirling water 22 feet tall, weighing 4800 lbs.

The structural design incorporates two types of isolation that work in tandem: (a) a swing-arm pendulum system with supplemental dampers and (b) a rocking system with yielding steel fuse plates. The first system is analogous to the swing-arm suspension and shock absorber systems commonly used in automobiles. The second system uses steel fuse plates, which attach the exhibit to the structural floor and have the hourglass shape used in the “ADAS” seismic dissipation systems studied at UC Berkeley in the 1980s. In large shaking the mounting plates can yield from overturning, but after shaking the exhibit’s gravity load restores the plates and vortex to their original position.

The swing-arm concept has potential for seismically isolating other structures such as equipment and vessels that have critical piping or electrical connections, for example, nuclear reactor vessels.