For designers

Constructional schemes


Arches are reliable, economic and relatively simple. Arches can span a distances between supports of up to 100 m and more. When distances between supports are greater, semi-arches made of several rigidly interconnected elements are used.


Frames and bracket systems are not widely used; they are usually used for covering stadiums, stands, piers and platforms, when the distance between supports is 40 m.
For multi-support structures use of frame systems is more efficient than use of double-support beams, since 20 to 40 per cent of timber is saved.
Frame structures, as well as arch structures provide broad possibilities to develop various solutions in plane or space.


Trusses can span between supports from 12 to 80 m. It is most effective to use trusses for spans between supports within 60 m.
Compared to fixed or variable cross-section beams, trusses require less timber, yet more metal. The use of timber and metal is influenced by the shape of the upper chord, while the bottom chord and the web can be both metal and timber.