FR2534301A1 - Permanent form for dismantlable paving poured on site. - Google Patents

Abstract

The invention relates to the production of protective paving for the impervious linings (membranes) for roofing/terraces with bearing elements made from masonry. The paving is installed in permanent forms which are arranged beforehand over all the surfaces to be protected. These forms comprise mould-forming lateral walls 4 for the mortar, stiffeners 1 on their bottom permitting the drainage of water under the mould. The bottom is pierced with holes 3 which are intended for draining the water impregnating the cement mortar. The elements placed side by side are connected by means of clips 2 which provide adjustment in terms of level and the pointing of contiguous forms.

Description

 The present invention relates to the hard protection of waterproofing coatings for flat roofs with load-bearing masonry elements.

In known devices of this type, the hard protections are made either by pouring a screed in fractioned mortar at regular intervals, or by prefabricated slabs and placed on the waterproofing coatings. In all cases, elements ensuring independence are interposed between the waterproofing coating and the added protection,
These devices each have drawbacks
- The first due to the fact that the protection thus produced cannot be dismantled in the event of a disaster linked to a defect (solution of continuity) in the waterproofing coating leading to water infiitrations in the underlying premises. must in this case be broken, which inevitably leads to degradation of the sealing coating.

 The second requires painful and dangerous handling of prefabricated slabs and a complex installation in front of emerging structures above the roof terrace. Furthermore, the realization of this type of protection is not very economical.

 The use of the lost formwork according to the invention makes it possible to avoid these drawbacks.

 In fact, the protective paving produced is entirely removable if necessary and also avoids handling heavy materials since it is poured in place like a screed with traditional mortar.

 The lost formwork according to the invention is made of plastic material and of a size allowing easy handling.

 Seen in plan from above it appears as a regular polygon or in any form which from assembled standardized elements makes it possible to constitute a surface without solution of continuity.

 Each element is a hollow plastic mold with a depth compatible with the final thickness of the hard protection to be produced.

Each mold has on its side walls a fruit with two uses to: - on the one hand prevent two elements placed side by side from touching each other over the entire height of the mold by possibly creating yawns in the upper part of two contiguous molds
- secondly make these elements stackable to facilitate their packaging and handling.

 Each mold also has at each of its angles an alveolus outside the side walls of the mold allowing the fitting of clips ensuring the adjustment of contiguous molds both in level and in the upper horizontal plane of the finished paving.

 Finally, the molds provide on their underside stiffeners made by molding the plastic material making up each lost formwork.

These stiffeners are of double use:
- on the one hand give more rigidity to each element of the lost formwork
- on the other hand facilitate the drainage of runoff water under the hard protection.

 Fig 1 shows a perspective on an assembly of lost formwork in the shape of a rectangular parallelepiped with a horizontal square section.

Fif 2 is a vertical section on a mold bottom stiffener 1
Fig 3 is a vertical section on a side wall 4 of the lost formwork.

The lost forms are placed next to each other on the surface of the surface to be treated. At each angle a clip2 is put in place to adjust the levels of the adjacent molds. The same clips bring the molds concerned together,
Once the entire surface has been covered, the cement mortar is poured by troweling the surface on advancement.

 To allow the evacuation of the mixing water from the mortar after pouring on the one hand, and that of rainwater soaking the slabs as part of the normal operation of the hard protection on the other hand, the bottom of the molds an plastic is pierced with small holes3 over their entire surface.

 After drying, the paving thus formed responds perfectly to its function. If necessary, the connection clips are extracted at the corners of one of the molds on the surface concerned and the slab in question is released by inserting a suitable tool into the openings of released clips.

 Speaking of this first slab, it is possible to deposit as many slabs as necessary.

 The slabs can be replaced in their location as well as the connecting clips.

 The device that is the subject of the invention can be used on all roof terraces that are accessible or require hard protection of waterproofing coatings. It can also be used in the manufacture of traditional pavements which would imply possible removal.

 The device in question avoids painful handling and allows the use of modern means of making paving such as mortar pumps.

Claims (5)

 1. Formwork lost in plastic material for the production of removable paving, in particular in the protection of waterproofing coatings on flat roofs with a load-bearing element for masonry, characterized in that the juxtaposition of standardized elements whose base is smaller than the part upper allows the realization of a paving without continuity solution.  2. Lost formwork according to claim 1 characterized in that the fruit of the side walls allows the stacking of several elements to facilitate the packaging and transport thereof.  3. Lost formwork according to claims 1 and 2 characterized in that the establishment of connection clips with the other formwork allows adjustment both in level and in the horizontal plane; The finished paving thus appearing without a solution of continuity, nor a projection on the whole of its surface.  4. Lost formwork according to claim 1 characterized by stiffeners at the bottom of the mold allowing better holding of the formwork and ensuring drainage of runoff water under the formwork after completion of the paving.  5. Lost formwork according to claim 1 characterized in that its bottom is pierced with holes over its entire surface to allow the evacuation of dimprgnation batten cement mortar which it serves as a mold.