Eagle Event Center

Nearly complete Eagle Event Center.

Exterior of the nearly complete Eagle Event Center in Hennessey, Oklahoma.

The Eagle Event Center is the multipurpose athletic, administration, and instruction facility at Hennessey Public Schools in Hennessey, Oklahoma. The 25,000 square foot (2,322 m²) structure includes a competition gymnasium for basketball, volleyball, and other athletic activities. The floor can also be covered with carpeted tile and used for dances, assemblies, and community events. There are four team locker rooms, a referee locker room, concession stands, a training center, walking track, and a 2,000 square foot (186 m²) lobby. The gym seats over 1,800 at athletic events and almost 2,000 for assemblies.

The Monolithic Dome is the first constructed using an inflated stem wall with a steel ring. The process is patented by South Industries with development assistance from Monolithic. There are two inflatable membranes, one for the dome and a second for the stem wall.

Timelapse of the inflation shows how the heavy steel ring is lifted by the form. A telescoping forklift controls the movement of the ring until the structure is fully inflated.

The dome membrane is 180-feet (54.9 m) diameter by 36-feet (11 m) tall. The stem wall membrane is 177.5-feet (54.1 m) diameter by 29-feet (8.8 m) tall. The two membranes are connected to a 15-ton (13.6 t) steel truss. When inflated, the ring-shaped truss is lifted into place, the membranes pressurize, and the form is finished. Standard Monolithic Dome construction continues inside with foam, steel, and concrete applied to the interior surface of both membranes. This creates a one-piece structure from the foundation to the top of the dome. A brick veneer is added later.

The center is also a FEMA P-361 rated tornado shelter. During a tornado warning, a signal unlocks the front doors and community residents can shelter in place until the storm passes.