STABILITY FARM. COMMUNICATIONS. GENERAL DIMENSIONS OF FARM.

Farm easily loses stability from its plane. In order to make the farm resilient, it must be attached to a rigid structure or connected with another farm, resulting in a spatial stable bar.

This bar is formed by two planes of paired trusses, two perpendicular bond planes located along both belts of the trusses and at least two planes of cross links (absol and a 'b' c 'd').

This timber has a very high rigidity in torsion and bending in the transverse direction.

Farms in building coatings that are interconnected by only one purlin do not form an immutable system; therefore, they have a free length from their own plane, equal to the span, and can easily lose stability.

GENERAL DIMENSIONS OF FARM.

A) Definition of span farms.

The span or length of trusses in most cases is determined by operational requirements. When the coating trusses are free supported by the supports (columns), the calculated span of the truss L (the distance between the axes of the supporting parts) is taken to be equal to the distance between the inner quarters of the supports, i.e.

L = L0 + a / 2, where

L is the clear distance between the supports,

and - the width of the support.

The height of the trusses is assumed to be 1/7 ÷ 1/9 of the span (in the span).

The slope of the farm (1/8 ÷ 1/12) L.

Because the load is applied to the truss nodes; the panels must correspond to the distance between the elements transferring the load to the truss. If the trusses are laid along the trusses, the panel equal to the distance between the runs is determined by the type of roofing deck and its length varies from 1.5 to 3 m. Rackless roofing covers are used in which the flooring in the form of reinforced concrete panels with a length of 6–12 m and a width of 1.5–3 m is laid directly on the belts of the trusses.

In this case, the stability of both the entire coverage and the individual elements of flat trusses is ensured by the fact that the construction of the coating creates several spatial stable blocks from two neighboring trusses, fastened both by connections in the plane of the upper and sometimes lower belts, as well as vertical transverse links between trusses of the truss, which replace the ties on the lower chord.