Completed in 1993, the Stratosphere Las Vegas Tower is the tallest freestanding observation tower in the United States, soaring 1149 feet above the ground. This complex design consists of a hexagonal-shaped central concrete tower with 20-foot-wide walls, positioned on a concrete foundation. Around this central tower at 120-degree intervals are three 20x32-foot rectangular bracing legs that incline toward the tower. At 260 feet up, the legs intercept the central tower, and these four elements join to form a single 112-foot-diameter section. Then the legs gradually incline outward to cradle the Stratosphere’s top structure—a 12-story, 145-foot-diameter pod. The pod houses a two-story revolving restaurant, two observation decks, meeting rooms, and thrill rides perched more than 1000 feet high.

The size and complexity of the Stratosphere project made formwork selection a real challenge. The project’s general contractor Leeman Corp., Las Vegas, decided to use custom-designed self-climbing gang forms to speed construction and reduce labor requirements. Although these forming systems usually are used for flat, perpendicular surfaces, the manufacturer was able to design self-climbing systems to accommodate the tower’s inclined, intercepting surfaces. Learn more about the Stratosphere’s design and construction.