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Description
Process for the execution of the foundation works of buildings erected with prefabricated structures.
This patent application relates to a new process for the execution of the foundation works of buildings erected with prefabricated elements that allows for a considerable reduction of erection time and costs compared to the systems currently used. The process according to the invention is particularly suitable for the construction on level ground of one-storey buildings that do not require deep foundations or piling works.
According to the current building technique, the foundation works of surface type mainly consists in ground excavations to create a perimetric hole that follows the direction of the external walls of the building to be erected; either prefabricated cases are positioned or wooden formworks arranged inside the said hole for the execution of the concrete casting after realizing reinforcement cages.
In case of large buildings provided with load bearing internal walls, the excavations are also carried out inside the perimeter, so that each load bearing wall lays on a corresponding girder located under the ground suitable to bear the loads transmitted by the structure above.
According to the current building technique, it can be said that the foundation works of surface type include the realization of a perimetric or reticular series of reinforced concrete girders, sunk in the ground, that are used to discharge and evenly distribute the load of the building on the ground, as well as to connect the plinths from which the various pillars used to support the floors and the roof project.
Once the supporting framework of the building is completed - including the covering - the external prefabricated panels are laid, followed by the flooring on the ground level inside the perimetric walls.
Having analyzed the process according to which the flooring is
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executed with different timing and tools compared to the foundation works, the applicant has devised a new process - that is faster and cheaper than the current one - for the execution of the foundation works of buildings erected with prefabricated structures on level ground whose geological nature does not require piling works.
The reduction in cost and time obtained with the process according to the present invention is due to the idea of simultaneously executing both the flooring and the foundation works on which the external and internal prefabricated panels of the building are laid. The process according to the invention comprises no excavation works, only the casting on the ground of a reinforced concrete platform having the same surface as the plan of the building, including the external perimetric sidewalks.
The main characteristic of the concrete platform is represented by the presence of a surface canalization that extends along the same direction as the external and internal walls of the building. More precisely, the width of the canalization is such that it allows for fixing the lower edge of the external and internal prefabricated panels of the building.
Another characteristic of the platform is represented by its leveled and treated surface that can act as the flooring of the building, meaning that the ceramic tiles, the wooden boards or any other material used for the floor and sidewalk coating can be directly applied on the said surface.
The supporting platform is realized by casting concrete inside a large footing form made up of perimetric sides used to contain the concrete and a series of internal moulds where the canalization is required. Once the concrete has consolidated and the internal moulds have been removed, their impression have created the above-mentioned surface canalization.
By using appropriate reference guiding profiles along the moulds and the perimetric sides of the footing form, the concrete casting can be properly leveled and treated before it consolidates, in order to create the various floors inside the perimetric walls and the external perimetric sidewalks.
Once these ground works have been completed, the erection of the
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building continues with the utmost easiness and speed, since it is only necessary to place the external and internal panels inside the canalization and firmly fix them by using the usual connecting and tightening means.
The building process according to this invention allows for a considerable reduction in time and cost in case of one-storey standard modular housing units with limited extension that are erected by only using prefabricated structures, including the roof that is directly laid on the perimetric walls.
For clearer explication purposes, the description of the process according to the present invention continues with reference to the enclosed drawing in which:
- Fig. 1 is a schematic axonometric view of a modular housing unit using a supporting platform erected with the building technique according to this invention; - Fig. 2 is a cross-section with a transversal plane of the said supporting base.
With reference to the above mentioned figures, the process according to the present invention includes the realization of a reinforced concrete platform (1) on the ground (P) having the same surface as the plan of the building (2), including the perimetric external sidewalks (3).
According to the present invention the platform (1) is created by using a special footing form, made up of perimetric sides and internal surface moulds, whose impression - once the concrete casting has consolidated and the moulds have been removed - consists in a series of raceways (4) in which the lower edges of the external and internal prefabricated panels (5) of the building (2) can be exactly placed and fixed.
According to the present invention, before the consolidation of the concrete casting, the casting is leveled and treated, so that the surface (1a) of the platform (1) can be directly used as supporting and anchoring plane for the coating material (M) chosen for the internal flooring of the building and of the perimetric sidewalks.