Underground structure below concrete stelae
The 2,711 massive concrete monoliths sit in a site area of more than 19,000m 2, varying in height and topography to create a wave-like motion.
Each stele has a wall thickness of 120-150mm for the vertical faces and 160-250mm for the top surface. The shuttering system was designed so that after 48 hours, each stele could be lifted, rotated and positioned in a workshop prior to the removal of the steel formwork, eliminating any contact to the fresh concrete surfaces and improving consistency of finish.
Surface treatments were then applied to avoid efflorescence and as graffiti protection.
Beneath the south-east corner of the site is the Ort (place) of Information for visitors and researchers. Its roof structure follows the form of the field that flows uninterrupted over the Ort building, which comprises four 14 x 14m rooms for information. A double-skin internal wall 920mm thick separates each room, accommodating ventilation, extract grills, vertical ductwork and structural reinforced concrete columns, leaving clear spans and providing wall area for information displays.
Positioned in the raised floor are fan coil units, which provide cooling and climate control of individual spaces. The foundation of the building is a solid 600mm raft. The roof slab, subject to the point loadings of the stelae, is a 800mm reinforced concrete waffle slab and is a negative of the field above - the ribs underlying the stelae's walls.
The fairfaced waffle slab soffit forms the ceiling of the themed rooms of information. Structural spans of the roof slab are 13m in each direction. Permanent steel anchors founded at depth below the Ort provide the permanent restraint against flotation of the building, which is below the water table.