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This bascule bridge spans the Potomac River near Washington, DC. This critical bridge, which carries over 250,000 vehicles each day, is in a low seismic zone. However, the redistribution of forces and performance under service-load conditions made Seismic Isolation an appealing option for the designers.

The elevated JFK light Rail System connects JFK Airport to the New York subway system. The bridge is 10 miles long and is supported by 1,364 DIS isolators. The design-build contractor chose isolation to save foundation costs. As the foundations were smaller, significant other cost savings were realized by minimizing the relocation of underground services at the airport and along Van Wyck Freeway.

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Reduced substructure forces in the isolated condition allow for aesthetic expression with sleek members in this bridge in Guadalajara, Mexico. The reduced foundation forces resulted in 50% fewer piles.

Isolation halved the foundation cost on this bridge in Mexicali. The foundations required only two-thirds of the concrete and one-third of the reinforcing steel that would have been required with a conventional design.

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