On more than 420 hectares a botanical garden is being created in the north of Oman. It recreates eight different habitats found in the country and, as largest of its kind on the Arabian Peninsula, provides an insight into the regional flora and fauna. Two large grid shells allow visitors to experience the different plant worlds.
The supporting structure of each dome is made up of a series of steel arches increasing in height towards the center of the building. Slightly bend in ground plan, the two structures blend in with the landscape. As each biome houses different plant species, their outer shell have to fulfill different requirements.
On the southern biome, horizontal bracing is provided by diagonal struts between the arches and along the top ridge, connecting the steel arches. In the northwestern part of this building, the arches at the bottom turn into columns, allowing a vertical facade in the entrance area. The outer cladding of the dome is supported by a secondary steel structure lying on top of the primary structure. It receives the glass panels and allows for tolerances and movements. Exterior shading elements provide sufficient protection from the sun for the plants.
For the north dome, transversal steel girders are rigidly connected to the arches to provide horizontal stiffening, thus eliminating the need for diagonal struts. Contrary to the southern building, these arches extend all the way to the ground. The glazing elements are mounted in a second structure that lies on top of the actual supporting structure. The shading is installed on the inside of the dome.
