Thanks to a structural-steel hat truss, the 10-story tower of the 240-ft-tall New United States Courthouse, Los Angeles, appears to balance on its core, hovering over the ground as if it were a sculpture on a pedestal.
The design, which elevates the bulk of the cube-shaped building off the ground and hangs it from the penthouse truss, improves defenses against vehicular assault at the street level. But minus perimeter columns at grade, the steel structure of the boxy tower was not self-supporting during construction. That meant some extra legwork—including an elaborate falsework system complete with hydraulic jacks—to build the $400-million courthouse, which is 70% complete.