In November 2012, the new Emporio Armani store opened its doors in the city centre of Vienna. A convincing and outstanding architectural highlight is the construction of the self-supporting stairs, which look like a sculpture in the stylish interior finishing of the showrooms. The construction and design of the self-supporting stairs with closed parapet-high stringers perfectly complies with modern style in architecture. This is largely due to the soffit lining, which is shaped by the spiral run of the stairs.
Construction of the stairs
With an inner diameter of 1,200 mm and an outer diameter of approx. 4,280 mm, this four-radius point circular staircase layout has a flight width of approx. 1,300 mm. The parapet-high stringers of the stairs consist of rectangular hollow sections in a closed-box design. The steps feature a folded-stairs design and are welded in between the stringers of the stairs. The spiral staircase is anchored with a steel base plate to the unfinished floor ensuring a force-fit connection.
Soffit lining for stairs
The underside soffit made of steel sheet is shaped according to the ascending spiral flight run of the stairs and welded in between the stair stringers. In order to meet structural requirements, the soffit lining of the stairs was dimensioned and calculated as a structurally supporting element. A CNC-controlled laser system ensuring the accurate cutting of the steel parts paired with supreme craftsman skills were required for this task. In order to reinforce the black-and-white look of the stairs, an exposed shadow gap borders the steps on both sides against the stair stringers, standing out appealingly against the trowelled Marmorino finish of the steel parts. Since the building is open to the public, fire protection requirements in accordance with E30 had to be complied with, which involved preventing flame penetration in the area between the stair stringers.
Structural requirements for spiral stairs
In addition to manufacturing and assembling the stairs, MetallArt was responsible for preparing a verifiable structural calculation in an FE model, which takes into account the live load requirements and the rail loads of the parapets.