Technical sheet

The arched structures in galvanized steel manufactured by us are controlled during production by our technical office which, apart from making the calculations, prepares all the designs for the workshop, in the most detailed manner.
All the steel structures are made taking into account the use of the fabric membrane cover, thus realizing a safe match with the same.
The structural part is made according to the regulations in force and especially according to what is stated below.

 

Reference standards

The structural dimension A done by following the indications of the following regulations:

EUROPEAN REFERENCE REGULATIONS

ITALIAN REFERENCE REGULATIONS

 

General description of the galvanized steel structure

Main structure characterized by arches with two or three bridges and secondary structure constructed with struts. Presence of steel bracing rods. The STATIC analysis which is carried out is of the elastic-linear type. The SISMIC analysis of the STRUCTURE which is carried out is of the dynamic modal type. The project is verified with the Limit State method.

 

Parcial coefficients for the actions or for their effects in the SLU verification

(see Point 2.6.1 – Tab. 2.6.1 – M.D. 14-01-2008)

Values of the combination coefficients

(see Point 2.5.3 – Tab. 2.5.1 – M.D. 14-01-2008)

The biaxial pretension of the fabric membrane covering is taken into consideration which, even if not foreseen by the regulations in force, exercises a constant load on the arch.

 

Details of the construction of the waterproofing of the membrane

The membrane cover is made up of a high resistance fabric in POLYESTER synthetic fibre and waterproofed by a layer of P.V.C. carried out on both sides. The membrane used for the covering of the laminated wood structure is in polyester, synthetic and rot-proof.
The name of the thread that makes it up is Dtex 1,500 and corresponds to the weight of a coil of 10,000 mt. of yarn. The mechanical characteristics of the membrane are chosen in function of the accidental overloading it undergoes and this takes place during planning.
The materials available are divided into 6 typologies with different characteristics and shown in the card provided.
Even the superficial lacquering can be of different types in function of the result to be obtained and the treatment used most consists in an acrylic lacquer.
The confection of the covering layer takes place through the interface of moulded strips in the cutting and welding phase at high frequency.
The membrane obtained in this way is one sole piece, even for large dimension coverings, without any possibility of infiltration or anything else at the interface.
The moulding obtained during the confection allows a curve between the arches thus obtaining two important results:

1) aesthetic validity as the moulded membrane presents itself as a double curved tensioned structure;
2) excellent distribution of the strain on the whole surface without dangerous concentrations and areas of little tension which move in the wind;
The confection then foresees a series of special accessories among which the most important are the steel traction cables and overload resistance, arch shaping to radially distribute the strains and used in particularly windy areas.
The covering obtained is lifted and spread over the wooden structure and anchored to the ground, in the standard version, in the two heads through pipes inserted in a special flap and anchored to the base of the structure, on the long sides, with special traction elements anchored to the galvanized wooden structure with application of the necessary pretension for a correct assembly.
In the version with “Baraccatura di Testata” the covering is anchored at the same height as the side ones.

It is highlighted how the pretension of the membrane covering and its double curved moulding are important for the long duration over time permitting an excellent distribution of the strains and a coefficient of high safety in all the areas of the membrane itself even in the hard conditions of overloading.
The lower structural part, completely vertical, is completed by a plugging, always in waterproof fabric covering which slides sideways, equipped with special rails and trolleys for suspension of membrane. This particular plugging allows easy and swift opening and closing operations, thus allowing the transformation in a short time from installation closed to installation open.
It is possible to also install double sheet with an insulating function on all our fabric coverings which is able to lower the coefficient of heat transmission with excellent results in reducing fuel consumption for winter heating and more than satisfying results for the reduction of the effects of solar radiation in the in-between seasons.
We are also able to apply the fan type “Energy” version to the arch structure coverings which is particularly profitable both in saving winter heating costs and for the chance to cool the internal environment with excellent results and low consumption, a particularly suitable solution for gyms and conference rooms.

 

ACCESSORIES

To complete our supplies the following installation accessories are available:
– Artificial lighting installations with mixed lamps or metal iodides;
– Artificial lighting installations with energy saving LED lamps;
– Emergency lighting installations;
– air heating installation with air blast or fan heaters;
– Air heating installations with generators with cutting edge condensing burners;
– Destratification installations wtih fabric diffusers with pressure pipeline;
– Special entrance of various sizes, even for vehicles;
– Height connections with metal gutters to existing works;
– Photovoltaic installations.