The roof structure evoking the shape of an umbrella was designed with showing consideration for the circular plan shape of the building and locations of the vertical elements as self-supporting structure placed on RC circular ring. The structure in its final technical design was designed as rigid space structure with glulam truss beams constrained to a central steel ring. Atypical shape of the ring with the central element connected to the compression tube so as to ensure precamber of the anchoring system for the system tension bars, thus creating desired spatial effect and ensuring spatial stability of the structure at the same time. The structure is stiffened with a system of steel tension bars and timber bracing elements. The purlins rest on trusses and the size of their profiles is decreasing towards the central ring (depending on span). The main trusses (together with the main tension bar) are attached to RC ring with the use of steel bearing.
The structure was erected with the aid of a temporary central support according to the detailed erection instructions. Each of the tension bars has been pre-tensioned to achieve required values that had been monitored by tensometer during the erection. After all the elements were completed and the shape of the structure checked by control survey, full activation of the structure by gradually letting down the central mounting support.
 
Materials:
Glued laminated timber - GL28h
Steel S355 and S460 (system tension bars)

Year of completion: 2014
Location: Velké Losiny