Sports Arena, Kadoma, Japan

The Kadoma Sports Center consists of the main arena with a racing pool and a diving pool of international standard, and the two adjacent arenas for volleyball and basketball and training pool. The floors of the pools in the main arena are movable, and can be converted to an ice-skating arena in winter. The dome itself is a double-layer, gridded space-frame of steel tubes with a depth of 2.6 m. There are a total of 3,601 joints in the dome and 10,572 members. For aesthetic reasons, the equator of the dome is inclined 5 degrees from the horizontal, which meant that the pre-assembled structural units had to be lifted non-vertically, an unusual erection challenge. The total weight of the structural steel is 11.86 MN.