San Francisco International Airport – Structural Engineering

As the centerpiece of San Francisco International Airport’s expansion project, the International Terminal has become a striking symbol of the city and the West Coast’s gateway to the Pacific Rim. The five-story structure represents a watershed in the integration of structural and architectural design and a model for other urban airports with limited developable land.

The main ticketing hall was inspired by the great railway stations of Europe. To minimize obstructions in the hall, which sits astride the airport’s main access roadways, SOM employed a series of double-cantilevered trusses linked by bowstring trusses. The aesthetic, proportioning, and profile of the main truss were continually refined throughout the design phases to achieve a maximum integration of form and economy. The result was the creation of a wing-like form, modeled after the famed 19th-century Firth of Forth Bridge, which directly expresses the structural diagram of its bending forces.

SOM introduced natural light throughout the building to clarify its structure and guide users through the massive facility. In the center span, a series of tensile structures diffuse light from above. The building’s west face features a translucent and pixel-fritted glass wall, which filters afternoon light while announcing the terminal as the airport’s entrance. SOM engineered the structure to the highest seismic safety requirements ever imposed on an American airport terminal, so that the facility will remain operational in the event of a major earthquake.