The existing Superbay Hangar is the largest hangar at SFO, capable of housing four 747 planes at one time, but did not have a fire suppression system capable of suppressing jet fuel fires. This design-build project included supporting 48 new foam generators and associated piping as well as a new sprinkler system from the light framed roof. The roof framing consists of steel space trusses that cantilever 300 ft from the central core that are warped hyperbolic paraboloids. The combination of highly variable geometry and the complex existing gravity system made the design of these mechanical supports especially challenging.
The project also included adding a new two-story pump house building to house pumps, piping, generators, and many other pieces of equipment. The pump house consists of concrete fill over metal deck floor supported on steel framing, CMU shear walls, and tubex pile foundations. Adjacent to the pump house are two new 50 ft diameter water tanks that are 50 ft tall. The tanks are supported on mat slabs over tubex piles. The tank foundations were designed considering the sloshing effect of the water during a seismic effect.
Videos of testing the new fire suppression system
LOCATION:
San Francisco, CA
CLIENT, OCCUPANCY:
San Francisco International Airport
CONTRACTOR/TEAM:
The Weitz Company
OCI Consulting Engineers
Tenenbaum/Manheim Engineers
CONSTRUCTION COST:
$38 M
SCALE:
260,000 sf existing hangar
6,600 sf pump house
(2) 50 ft diameter water tanks
CONSTRUCTION TYPE:
Existing steel framed hangar and steel frame with concrete walls pump house
ROLE:
RJSD was a subconsultant to Tenenbaum/Manheim Engineers
History
The Superbay Hangar was originally designed by Lev Zetlin, Charles H.J. Thornton and Richard L. Tomasetti, and was the worlds largest light-gage steel primary structure when constructed. The exact hangar was built at several airports, but only two currently remain, one at SFO and one at LAX. The hangar is an important facility for SFO, so the first task of the project was a Revit model of the entire building for future facility use. RJSD created the Revit model, which was invaluable for the later design phases of the project. The roof deck of space trusses serves double duty structurally as both the roof diaphragm and the webs of the space trusses. Post tensioned cables extend from the central core to the cantilever tips to reduce shear stresses. These elements required careful analytical modeling to make sure the existing roof could support the new loads.
Foam fills SFO hangar in firefighting drill
SFGATE July 24, 2020