FR2555630A1 - Method for producing insulating floors using elements, as well as the elements and floors produced by the said method - Google Patents

Abstract

The invention relates to self-supporting prefabricated elements which are ready for use. They are characterised by the combination: a. of a lower part made of insulating material, the external shape of which is inscribed in a right-angled parallelipiped comprising a plane base, symmetrical lateral faces with grooves 42, 43, ribs incorporated longitudinally, transverse ribs joining the longitudinal ribs, concrete ends connecting the concrete slab and the longitudinal concrete ribs; b. and of an upper part or slab 13 made of reinforced concrete, the main reinforcement elements of which are located at the bottom of the longitudinal ribs, within the height of the latter and in the upper plane part of the said upper part.

Description

Technical area
The present invention relates to a method of manufacturing insulating floors based on prefabricated self-supporting elements consisting of a slab ribbed in
reinforced concrete, possibly prestressed, having at least two ribs, cast in a mold made of thermally insulating material and connected with identical slabs, on the site, by a keying mortar and fixed to the self-supporting walls by a hainaqe. It also relates to the ready-to-use nuto-psrtarts manufactured elements manufactured according to said process as well as the floors manufactured using said elements.

Probibe posed
It has to realize reinforced concrete or pre-stressed concrete floors incorporating good insulation in order to cope with the energy savings that are increasingly on the agenda. Indeed, in most cases, so far, conventional concrete floors are poured to which it is necessary to adapt a thermal insulation a posteriori, which increases the duration of construction and is expensive.

State of the art and disadvantages
Up to now, an approach has been made to the solution of this problem by the realization of various kinds of prefabricated floors or cast in place which required at least two interventions. Among these methods, we can cite: a) - the installation of beams and interjoists
- followed by the pouring of a compressian slab.

b) - pouring an ordinary floor
- the installation of an insulator.

These two operations are commonly followed by the pouring of a protective cover c) - the juxtaposition of beams with a T-section cast in a lost mold in insulating material,
- the keyness of these beams.

 The last process requires a mold of great complexity which does not allow simple extrusion, several interventions being necessary.

 More specifically, one can cite in these fields: the German patent 2,436,515 which describes elements in which the resistant part is either a lattice beam with reinforced concrete (Figure 1), or a reinforced concrete or prestressed concrete beam large inverted T (figure 2), either a reinforced or prestressed I-shaped concrete beam (figure 3).

 The connection of these beams is done by interlocking in rebates or by zigzag section joints. The beams are embedded in a porous concrete and not very resistant which requires placing them very close to each other. This results in the impossibility of practicing hoppers and a reduction in resistance during thrusts perpendicular to the axis of the beams.

 French patent 2,432,578 which describes elements whose resistant ribs are a reinforced concrete beam with a lattice frame with pre-coated heels.

The entire floor compression table made up of these elements is poured and worked, which requires the large quantity of concrete on site. In addition, it can be seen that the lower exterior facing part has a different composition from the insulating sides (reference 2 in the figures), which implies a heterogeneity in the composition of the floor or, more precisely, a defect in mechanical connection between the insulating part. lower of said floor and the resistant part of reinforced concrete which constitutes its upper part.

 In the same way as in the previous German patent, the essential part of the beams is constituted by a cellular plastic material which lacks resistance in the forces directed in directions perpendicular to the axis of the beams and the keying of said beams is too slsoF) lified since it is carried out by said cellular plastic material; this can lead to mechanical resistance and cohesion defects between the different juxtaposed beams. This results in a heterogeneity of the floor formed.

British patent 1,540,575 provides for reinforced concrete elements poured into wooden forms. It also provides for a compression table cast in action which, once again, imposes the contribution of very large quantities of reinforced concrete on the site. Its good stitching with the low frames is ensured by Greek-shaped irons represented on the filter 4. Here again, as these are juxtaposed beam structures as indicated in the references mentioned above, the floors made with
These reinforced concrete elements have the same drawbacks.

 British patent 432,479 provides for elements which may be made of reinforced concrete, the connection of which is ensured by indentations allowing neighboring embedding in each other. There is no easy connection between the various juxtaposed elements and we still fall into the same drawbacks of the documents which have just been cited.

 The present invention is intended to remedy the aforementioned defects by technical devices which will now be explained.

Statement of the invention
The present invention is characterized first of all by a manufacturing process which combines the following operations a) prior manufacturing of a formwork lost in base in thermally insulating material whose external shape is inscribed in a rectangular parallelepiped having - the base and the four planar cutis, - the lateral faces with a horizontal trapezoid-shaped groove, - a top hollowed out at least twice, by longitudinal grooves whose bottom is wider than the entrance and hollowed out at least once additional transversely, b) positioning in the rectangular trapezoidal grooves of tubules with symmetrical decagonal sections around their vertical median plane, having lateral bulges and emerging upwards, from the basic formwork provided for in a), of a dimension corresponding to the minimum thickness e of the upper concrete slab, said rods protruding at each end from said base formwork for supp orter two formwork of tynpan or end piece with means to facilitate the placement of reinforcement, c) placement of reinforcement and concrete, as well as preparation of elements by taking the latter, d) disassembly of the formwork elements described in b), e) transport and combination of the self-supporting prefabricated elements based on ribbed slabs which are generally placed side by side, f) keying in place in the grooves in the shape of a rectangular trapezoid surmounted by a bulge and pouring of the chaining to load-bearing walls.

 With this process, it is possible to manufacture ready-to-use load-bearing elements which are remarkable for the combination of the following characteristics a) of a lower part made of insulating material whose external shape is inscribed in a rectangular parallelepiped having - a flat base, - symmetrical lateral faces with grooves in the upper part, the lower part of which has the shape of a rectangular trapezoid and the upper part of which has a re-entrant angle, - ribs incorporated longitudinally with a lower section more important than the upper section, - transverse ribs joining the longitudinal ribs, - concrete ends connecting the concrete slab and the longitudinal concrete ribs so as to wrap the insulating material.

b) an upper part or reinforced concrete slab, the main reinforcements of which are located at the bottom of the longitudinal ribs, in the height of the latter and in the upper planar part, said upper part being obtained by filling in the recesses described above.

Solution to the problem, advantages and industrial results
It is understood that the device of the invention overcomes the difficulties described at the beginning of this meritorious by making a simple mold and a prefabricated floor composed of elements comprising several beams, the keyways being thereby reduced in number. This process allows the manufacture of elements comprising hoppers of the order of one meter on a side and this easily. This advantage could not exist in the prior methods and in particular with the devices described in the four patents mentioned above.

 Naturally, it is understood that the elements of the invention solve the problem of rapidly producing concrete floors incorporating the insulation, which avoids the subsequent laying of the latter. Most of the time, the insulation occupies the entire bottom surface of the floor. However, as will be seen in the description below, in certain cases, the mold can be simplified and the lower part removed, which reveals the underside of the transverse longitudinal ribs. One might think that this constitutes thermal bridges but the thickness of the concrete at this location is sufficient to reduce the effect. In addition, the floors formed by the method of the invention are generally intended to be placed between two floors of a building where the temperature differences are small.

 It is obvious that reinforced concrete contributes to most of the mechanical strength of floors. However, the resistance of the insulating material which also contributes to the cohesion of the floor should not be required. These insulating materials can be chosen from all the ranges currently known, and in particular from fire-resistant materials. We know that there is fire retardant pol yestyrene, high density polyurethane foams, phenolic foams, materials based on verniculite, wood, etc ...

 The invention will be better understood using the description below which shows some nonlimiting examples of practical embodiment which are illustrated by the accompanying drawings.

Brief description of the figures
In these drawings,
Figure 1 is a perspective view of a basic embodiment of the basic lost formwork;
Figure 2 is a perspective view of the same formwork, shown in dotted lines, to which has been added, in the grooves in the shape of a rectangular trapezoid, the rods of decagonal section supporting a tympanum formwork;
Figure 3 is a perspective view of the formwork shown in Figure 2 in which the eardrums have been removed, for clarity, and where the concrete constituting the ribs and the upper surface slab has just been poured;
Figure 4 is a perspective view of the finished slab, cut at one end, and stripped, including these side rods with decagonal section;
Figure 5 is a vertical longitudinal section of a prefabricated self-supporting element ready for use with a hopper located between two longitudinal ribs and two transverse ribs
the fife 6 is a plan view of the prefabricated element shown in Figure 5 ;;
FIG. 7 is a section of the prefabricated element shown in FIGS. 5 and 6 transversely, at the rights of the hole, along lines II and II-II of FIGS. 5 and 6, respectively
Figure 8 is a vertical cross section of two elements of the invention juxtaposed immediately before the keying operation
Figure 9 is a section similar to that of Figure 8 but made after the keying operation
Figure 10 is a longitudinal section of an element of the invention placed on two load-bearing walls;
Figure 11 is a section along III-III of Figure 10;
FIG. 12 is a section on IV-IV of FIG. 10.

Description of an implementation procedure
To manufacture a self-supporting element ready for use, according to the invention, a lost formwork (1) is used, which will be designated below as "basic lost formwork" made of thermally insulating material. This material can be, for example, expanded polyester foam, high density polyurethane foam, a product based on vermiculite or the like. Externally, this lost formwork (1) is roughly a rectangular parallelepiped. Its base and its four sides are planar but its lateral faces each have a groove (2, 3) with a cross section in the shape of a horizontal rectangle trapezoid. The top of the lost formwork has two longitudinal grooves (4, 5) which have been shown in the form of a dovetail, but, more generally, they have a wider bottom than their entry. The top also has at least one transverse groove (6).

 To this formwork (1), tubs (7, 3) are added laterally (FIG. 2) which have a symmetrical decagonal section around their vertical median plane. The rods (7, 8) have lateral bulges (9, 10, 11, 12).

Said rods (7, 8) emerge towards the top of the formwork (1) of a dimension corresponding to the thickness e (FIG. 3) of the upper concrete slab (13) which will be discussed in more detail below. after.

 The rods (7, 8) protrude at each end of the formwork (1) to support two forms (14) of eardrums which can also be called end formwork. The forms (14) have notches (15, 16) intended to facilitate the placement of the reinforcements (17) (FIG. 10) which will be discussed below.

 The overall formwork thus formed is then completed by pouring in the tone, as shown in Figure 3, so as to fill the grooves (4, 5, 6) and to form an upper slab (13) which touches the upper part of the sticks (7, 8). When these are removed, a ready-to-use self-supporting prefabricated element (18) is obtained as shown in FIGS. 4 to 12.

This element obviously includes the lost formwork (1), longitudinal (19, 20) and transverse (21, 22) ribs. Between these ribs, a hopper (23) can be provided which has been previously reserved by a special formwork. At each end we also get transverse ribs
(24, 25) or about.

To constitute a floor, there are several self-supporting prefabricated elements (18), one next to the
others, as shown in Figure 8. Then pour a concrete
or a key cement (26) (Figure 9). Naturally,
elements (la) (figure lr, upstream placed on two walls such as (27) and (28). The reinforcing bars of the reinforced concrete which will have been possibly and most often placed beforehand in the grooves (4) and (5 ) before pouring the concrete pass at the ends, through the notches (15, 16) of the tympanum formwork (14) and make it erect (27, 2E 'beyond the ends of the beam, above the walls (27) and (28) At this point, pouring concrete is poured.

 Other variants can be used to make the formwork (1). In particular, the distance existing between the ribs (19, 20) and the top of the formwork (1) is variable. It can be zero. The formwork (1) can be made in one piece, for example, from extruded material, or it can be made in several pieces with glued elements.

Claims (3)

 1. Method of manufacturing insulating floors based on prefabricated self-supporting elements consisting of a ribbed slab of reinforced concrete, possibly prestressed, having two ribs, at least, cast in a mold made of thermally insulating material and connected with slabs identical, on the site, by a keying mortar and fixed to the self-supporting walls by a chainage, characterized by the combination of the following operations a) prior manufacturing of a lost formwork (1) of basic insulating material thermally, the external shape of which is inscribed in a rectangular parallelepiped having - the base and the four flat sides, - the lateral faces with a groove (2, 3) with a cross section in the shape of a horizontal rectangular trapezoid, - a top hollowed out twice, at less, by longitudinal grooves (4, 5) -whose bottom is wider than the entrance and hollowed out, at least once, additionally (6) transversely, b) placed in the grooves (4, 5 ) in the shape of a rectangular trapezoid of rods (7, 8) with symmetrical decagonal sections around their vertical median plane, having lateral bulges (9, 10, 11, 12) and emerging upwards, from the basic formwork provided for in a) , of a dimension corresponding to the minimum thickness e of the upper concrete slab (13), said rods (7, 8) projecting, at each end, said base casing t1) to support two forms (14) of tx , mpar or flbOI.t presf ntant means to facilitate the placement of reinforcements, c) placement of reinforcements and concrete, as well as preparation of the elements by taking the latter, d) disassembly of the formwork elements described in b), e) transport and combination of the self-supporting prefabricated elements based on ribbed slabs which are generally placed side by side, f) keying in place in the grooves in the shape of a rectangular trapezium surmounted by a bulge and pouring of the chaining to load-bearing walls.  2. Prefabricated self-supporting elements ready for use manufactured according to the process provided for in claim 1, under paragraphs å), b), c) and d) which are characterized by the combination a) of a lower part (1) of insulating material whose external shape is inscribed in a rectangular parallelepiped having - a flat base, - symmetrical lateral faces with grooves (42, 43) in the upper part whose lower part has the shape of '' a rectangular trapezoid and the upper part of which has a re-entrant angle (44, 45), - longitudinally incorporated ribs (19, 20) with a lower section larger than the upper section, - transverse ribs (21, 22) joining the longitudinal ribs (19, 20) - of concrete ends (2, 25) connecting the concrete slab (13) and the longitudinal ribs (19, 20) of concrete so as to wrap the insulating material (1) and , to serve as supports on the load-bearing elements. b) an upper part or reinforced concrete slab (13) whose main reinforcements (30, 31) are located at the bottom of the longitudinal ribs, in the height of the latter and in the upper planar part, said upper part being obtained by filling in the recesses described above.  3. Floor manufactured by the combination of elements as finished in claim 2.