They are manufactured using high tensile strength prestressed strands, wires or single wire which are embedded within the element.
The production of these elements is achieved using our Slipformer machine that casts elements continuously on a long production bed without the need of any formwork.
A lighter floor can be made by using polystyrene in-fill blocks and then a floor covering or by creating voids within the floor using corrugated steel sheets or thin concrete slabs over the elements.
The ribs and lower part of the beams are also reinforced with steel mesh. The side profile is wedge shaped with a rough surface to allow the in-situ concrete to be easily applied.
The two ribs give the beam a high torsional rigidity and excellent transversal load distribution. This means that the element is self supporting during the transport and construction phases.
The main applications for these beams are:
They can be used with a prefabricated structure or with an on-site cast structure with joints designed to meet the technical specifications required.
The beams can be manufactured with heights from 500 mm to 1000 mm and with a standard width of 1200 mm or, by using the same machine, in a width of 800 mm simply by changing the internal side formers of the Slipformer.
The produced elements have high load resistances thanks to a low water/cement ratio of concrete from 0.32 to 0.38. In fact to produce the same profiles using traditional methods would require higher water/cement ratios and need expensive formworks.
Even though the low water/cement ratio employed makes the concrete hard to work, NORDIMPIANTI’s machines have no difficulty producing particular element shapes with a high level of reliability.
They are very common in the traditional building sector, in prefabricated building construction and also in seismic zones. For this specific purpose the floor elements can be connected to each other using steel reinforcement during construction in order to create floor continuity. This gives the floor the correct static characteristics required for seismic zones.
Through the choice of a different thickness of the lower part of the element, floors can be produced with high fire resistances of up to 180 minutes.
Large production volumes with uniform cross sections even with different cable reinforcement configurations are possible. Once the concrete elements have been produced they can be removed from the casting beds after just 8-10 hours.
In residential applications only final smoothing is required greatly reducing costs.
It is a quick and simple operation to change the necessary parts of the forming insert of the casting machine to vary the height and the thickness of the concrete elements.
For the most demanding applications or when producing high concrete elements, the lower part of the element and the vertical ribs are reinforced with steel mesh and connection bars.
The quality of the casting machines ensures a high compaction level and impermeability combined with a high mechanical resistance.