CH678551A5

CH678551A5 - Internal shuttering element esp. for making hollow concrete structure - comprises box e.g. of plastic, with inner reinforcing element

Info

Publication number: CH678551A5
Application number: CH4253/88A
Authority: CH
Inventors: Frederic Lancoud
Original assignee: Jahnle & Cie S A F
Priority date: 1988-11-16
Filing date: 1988-11-16
Publication date: 1991-09-30

Abstract

Internal shuttering element, for making a hollow moulded concrete structure, consists of a box (10) of the appropriate dimensions and equipped with an inner reinforcing element (20) to prevent it from collapsing. The box can be made from a cut and folded sheet of plastic, e.g. polypropylene, with closing end flaps (16, 17). The reinforcing element can be made from strips of plastic, cardboard or metal, cut lengthwise for half their length to that they can be slotted together to make a rigid structure. Both the box and reinforcing element can be folded flat for transport and storage. ADVANTAGE - More convenient to use, as it does not adhere to concrete, and can be removed for re-use once concrete has set sufficiently.

Description

       

  
 



  La présente invention est du domaine de la construction et concerne plus particulièrement un coffrage utilisé dans la technique du béton coulé. 



  Sur les chantiers, il est connu d'utiliser des planches en bois, destinées à limiter par exemple les parois latérales d'un mur coulé en béton. Lorsque l'on a besoin d'obtenir une ouverture ou un dégagement dans un coulage, on a par analogie pris l'habitude de façonner un caisson - de bois ou de sagex - aux dimensions requises dans chaque cas particulier. 



  Ces caissons de bois ou de sagex sont par contre très difficiles à retirer, car le béton s'introduit dans les veines du bois ou dans tout interstice superficiel. Lorsque la prise du béton est réalisée, il est souvent impossible d'enlever les caissons sans un travail long et fastidieux visant dans un premier temps à casser les caissons de coffrage, et ensuite à enlever les débris pris dans le béton. 



  La présente invention vise à pallier cet inconvénient et a pour objet un caisson de coffrage destiné à créer un évidement dans un coulage de béton. 



  Le caisson de coffrage est caractérisé en ce qu'il comporte un boîte renforcée par une armature intérieure tridimensionnelle amovible. Dans une forme d'exécution, la boîte et son armature sont agencées pour pouvoir être conditionnées repliées, de manière à occuper un volume réduit, puis déployées lors de leur utilisation. 



  Dans une forme d'exécution préférentielle, la boîte extérieure est un cartonnage en polypropylène extrudé tandis que le remplissage est constitué par un alvéolage en carton. 



  Un tel caisson est particulièrement avantageux car son prix de revient est d'environ le tiers de celui d'un caisson en bois traditionnel, et qu'il permet de plus de diminuer le temps de décoffrage et d'éviter l'obligation, dans certains cas, de retirer les débris englobés dans le béton. 



  Il est de plus très léger et peut être livré à plat ou monté. Il est aussi possible de grouper plusieurs caissons. Un avantage supplémentaire du caisson selon l'invention est qu'il peut être réutilisé, puisqu'il ne craint pas l'humidité et ne présente aucune adhérence au béton. 



  On peut aussi choisir différents coloris de l'enveloppe extérieure, correspondant à des dimensions différentes qui sont de ce fait repérées automatiquement. En variante, on peut encore imprimer des indications  complémentaires facilitant l'identification ou le positionnement des éléments. 



  En variante, certaines parois de la boîte pourront rester en place et faire office de gaine, après que le remplissage intérieur et les extrémités aient été retirées. Pour faciliter cette opération, on prévoira avantageusement des perforations facilitant l'arrachage des extrémités à retirer. 



  L'invention s'étend également à un procédé de fabrication d'un caisson ainsi qu'à une utilisation de celui-ci. 



  Le dessin annexé représente, à titre d'exemple non limitatif, une forme d'exécution de l'objet de la présente invention. 
 
   La fig. 1 est une vue générale en perspective d'un caisson selon l'invention. 
   La fig. 2 représente, en perspective éclatée, la boîte ouverte et son remplissage. 
 



  La boîte 10 est de forme parallélipipédique et peut être réalisée par un découpage dans une feuille de plastique, par exemple du polypropylène extrudé ou tout autre dérivé du plastique tel que polyéthylène ou polyvinyle. Le polypropylène a l'avantage d'offrir une bonne résistance mécanique et d'autoriser le découpage et le pliage à froid. 



  Le découpage constituant la boîte 10 comporte quatre parois latérales 11, 12, 13, 14 et un rebord 15, ainsi que deux parois terminales 16 et 17. De manière  connue de l'homme de métier, des lignes de pliures sont marquées entre ces différentes parois. 



  Le rebord 15 est destiné à être solidarisé avec la paroi 11 par tous moyens de fixation, par exemple des agraffes, une couture, une soudure ou par collage, à chaud ou à froid. 



  Comme représenté à la fig. 2, les parois terminales 16 et 17 peuvent venir de fabrication avec le fond 14 ou être en variante rapportées, selon les dimensions de la boîte désirée et des feuilles utilisées comme matière première. La liaison éventuelle entre le fond 14 et les parois terminales 16 et 17 sera réalisée comme indiqué plus haut pour le rebord 15 sur la paroi 11. 



  Les trois bords libres des parois terminales 16 et 17 comportent chacune une languette 161 et 171 respectivement. Chaque languette est de forme générale rectangulaire, ses angles extérieurs étant arrondis, et est séparée du bord correspondant par une marque de pliage 162 et 172 respectivement, représentée en pointillé au dessin. 



  Chaque bord libre des parois latérales 11, 12 et 13 comporte un rabat 18 et 19 séparé du bord correspondant par une marque de pliage 181, 191 et présente dans sa partie centrale une fente 182, 192 parallèle au pliage 181, 191 et de dimension légèrement supérieure à celle des languettes 161 et 171. 



  Il est à noter qu'à la fig. 2 on a représenté les rabats avant 18 en position repliée de 90 DEG  vers l'intérieur tandis que les rabats arrières 19 sont dans le prolongement de la paroi latérale correspondante. 



  La boîte 10 est destinée à contenir un remplissage alvéolé 20, constitué par exemple par des croisillons formés de plaques verticales 21 et de plaques horizontales 22 disposées en nid d'abeilles. Chaque plaque verticale 21 comporte, sur la moitié de sa longueur, des fentes parallèles 23, en nombre correspondant aux plaques horizontales 22 et de largeur légèrement supérieure à l'épaisseur de celles-ci. Inversement, chaque plaque horizontale 22 comporte, sur la moitié de sa longueur, des fentes parallèles 24, en nombre correspondant aux plaques verticales 21 et de largeur légèrement supérieure à l'épaisseur de celles-ci. 



  A titre indicatif, on peut signaler que la feuille de polypropylène a une épaisseur de 0,5 à 2 mm, pour une boîte dont la plus grande dimension atteint jusqu'à environ 1 m, alors que les plaques de cartons 21 et 22 ont une épaisseur d'environ 3 à 4 mm et sont espacées tous les 5 cm environ. 



  Lors du montage, les plaques verticales 21 et horizontales 22 sont imbriquées de manière à constituer des croisillons en nid d'abeille. Il est à noter que la largeur des fentes 23 et 24 permet le rangement à plat du remplissage, les plaques verticales 21 et horizontales 22 pouvant être disposées sensiblement parallèlement, afin d'occuper moins de place jusqu'au moment de leur utilisation sur le chantier. 



   De même la boîte 10 peut être transportée à plat, même lorsque la liaison entre le rebord 15 et la paroi 11 a été réalisée, les languettes 161 et 171, de même que les rabats 18 et 19 restant dans le plan des parois qu'ils prolongent. 



  Lors de leur utilisation, les caissons sont montés de la manière suivante. La boîte 10 est ouverte et le remplissage 20 y est introduit. Les rabats 18 et 19 sont repliés vers l'intérieur le long des marques de pliage 181 et 191. Les parois terminales 16 et 17 sont rabattues et les languettes 161 et 171 introduites dans les fentes correspondantes 182 et 192. 



  On obtient ainsi un caisson, très léger, résistant à l'humidité et qui ne présente aucune adhérence au béton, de sorte qu'il peut être aisément retiré et même réutilisé. Pourtant lorsque le caisson de coffrage sert à délimiter un passage de gaine, il peut être intéressant de laisser dans la dalle ou la paroi de béton les parois latérales 11 à 14 et de retirer les parois terminales 16 et 17, ainsi que le remplissage intérieur 20. Pour faciliter cette opération, on peut prévoir des lignes de perforations schématisées au dessin en 121 facilitant le déchirement des parois à enlever par rapport à celles formant la gaine. Il va sans dire que les lignes de perforations peuvent être à un autre emplacement que celui représenté au dessin, par exemple dans les pliures bordant la boîte. 



  Il est encore prévu d'utiliser des feuilles de couleurs variées, afin de distinguer des caissons de dimensions différentes. On peut également envisager d'imprimer des indications sur l'une ou plusieurs des faces, permettant de repérer plus aisément encore le positionnement des caissons. 



   Il est bien sûr possible d'utiliser, selon les besoins spécifiques, un seul caisson ou plusieurs groupés, que l'on peut fixer par exemple avec un cerclage au moyen  d'une bande plastique, telle qu'utilisée dans les emballages. 



  La description ci-dessus porte sur un caisson parallélipipédique, mais il est bien sûr possible sans sortir du cadre de la présente invention d'envisager d'autres formes, par exemple une boîte tubulaire de section triangulaire, circulaire, ovalisée, etc. 



  On peut prévoir de fabriquer ces caissons sur demande ou selon des formats standard. 



  En variante, on peut envisager de réaliser le remplissage intérieur avec des panneaux de cartons alvéolés ou avec un matériau expansé destiné à durcir après dilatation. On pourrait aussi utiliser des plaques en plastique ou des assemblages métalliques, éventuellement articulés. 



  
 



  The present invention is in the field of construction and relates more particularly to a formwork used in the technique of poured concrete.



  On construction sites, it is known to use wooden planks, intended for example to limit the side walls of a poured concrete wall. When one needs to obtain an opening or a clearance in a pouring, one has by analogy taken the habit of shaping a box - of wood or sagex - with the dimensions required in each particular case.



  These wooden or sagex boxes, on the other hand, are very difficult to remove, because the concrete is introduced into the veins of the wood or into any surface interstice. When the setting of the concrete is carried out, it is often impossible to remove the boxes without a long and tedious work aiming at first to break the formwork boxes, and then to remove the debris caught in the concrete.



  The present invention seeks to overcome this drawback and relates to a formwork box intended to create a recess in a concrete pour.



  The formwork box is characterized in that it comprises a box reinforced by a removable three-dimensional interior frame. In one embodiment, the box and its frame are arranged so that they can be packaged folded, so as to occupy a reduced volume, and then deployed during their use.



  In a preferred embodiment, the outer box is a carton made of extruded polypropylene while the filling is constituted by a cardboard honeycomb.



  Such a box is particularly advantageous because its cost price is around a third of that of a traditional wooden box, and it also makes it possible to reduce the formwork time and avoid the obligation, in certain case, remove the debris embedded in the concrete.



  It is also very light and can be delivered flat or assembled. It is also possible to group several boxes. An additional advantage of the box according to the invention is that it can be reused, since it does not fear humidity and has no adhesion to concrete.



  You can also choose different colors of the outer envelope, corresponding to different dimensions which are therefore automatically identified. Alternatively, it is also possible to print additional indications facilitating the identification or the positioning of the elements.



  As a variant, certain walls of the box may remain in place and act as a sheath, after the interior filling and the ends have been removed. To facilitate this operation, it is advantageous to provide perforations facilitating the tearing of the ends to be removed.



  The invention also extends to a method of manufacturing a box as well as to a use thereof.



  The appended drawing represents, by way of nonlimiting example, an embodiment of the object of the present invention.
 
   Fig. 1 is a general perspective view of a box according to the invention.
   Fig. 2 shows, in exploded perspective, the open box and its filling.
 



  The box 10 is of rectangular shape and can be produced by cutting from a plastic sheet, for example extruded polypropylene or any other derivative of plastic such as polyethylene or polyvinyl. Polypropylene has the advantage of offering good mechanical resistance and of allowing cold cutting and bending.



  The cutout constituting the box 10 has four side walls 11, 12, 13, 14 and a flange 15, as well as two end walls 16 and 17. In a manner known to those skilled in the art, fold lines are marked between these different walls.



  The flange 15 is intended to be secured to the wall 11 by any fixing means, for example staples, sewing, welding or by gluing, hot or cold.



  As shown in fig. 2, the end walls 16 and 17 can come from manufacture with the bottom 14 or be added as an alternative, depending on the dimensions of the desired box and of the sheets used as raw material. The possible connection between the bottom 14 and the end walls 16 and 17 will be carried out as indicated above for the rim 15 on the wall 11.



  The three free edges of the end walls 16 and 17 each have a tongue 161 and 171 respectively. Each tongue is of generally rectangular shape, its external angles being rounded, and is separated from the corresponding edge by a fold mark 162 and 172 respectively, shown in dotted lines in the drawing.



  Each free edge of the side walls 11, 12 and 13 has a flap 18 and 19 separated from the corresponding edge by a fold mark 181, 191 and has in its central part a slot 182, 192 parallel to the fold 181, 191 and of dimension slightly greater than that of the tabs 161 and 171.



  It should be noted that in fig. 2 shows the front flaps 18 in the folded position of 90 DEG inward while the rear flaps 19 are in the extension of the corresponding side wall.



  The box 10 is intended to contain a honeycomb filling 20, constituted for example by braces formed by vertical plates 21 and horizontal plates 22 arranged in honeycomb. Each vertical plate 21 has, over half its length, parallel slots 23, in number corresponding to the horizontal plates 22 and of width slightly greater than the thickness of the latter. Conversely, each horizontal plate 22 has, over half of its length, parallel slots 24, in number corresponding to the vertical plates 21 and of width slightly greater than the thickness of the latter.



  As an indication, it can be noted that the polypropylene sheet has a thickness of 0.5 to 2 mm, for a box whose largest dimension reaches up to about 1 m, while the cardboard plates 21 and 22 have a thickness of approximately 3 to 4 mm and are spaced approximately every 5 cm.



  During assembly, the vertical plates 21 and horizontal 22 are nested so as to constitute honeycomb cross-pieces. It should be noted that the width of the slots 23 and 24 allows the storage flat of the filling, the vertical plates 21 and horizontal 22 can be arranged substantially parallel, in order to occupy less space until the time of their use on the site. .



   Similarly, the box 10 can be transported flat, even when the connection between the flange 15 and the wall 11 has been made, the tongues 161 and 171, as well as the flaps 18 and 19 remaining in the plane of the walls which they extend.



  When in use, the boxes are mounted as follows. The box 10 is opened and the filling 20 is introduced there. The flaps 18 and 19 are folded inwards along the fold marks 181 and 191. The end walls 16 and 17 are folded down and the tabs 161 and 171 inserted into the corresponding slots 182 and 192.



  This gives a very light, moisture-resistant casing which has no adhesion to concrete, so that it can be easily removed and even reused. However, when the formwork box serves to delimit a duct passage, it may be advantageous to leave the side walls 11 to 14 in the concrete slab or wall and to remove the end walls 16 and 17, as well as the interior filling 20 To facilitate this operation, it is possible to provide perforation lines shown diagrammatically in the drawing at 121 facilitating the tearing of the walls to be removed relative to those forming the sheath. It goes without saying that the lines of perforations can be in another location than that shown in the drawing, for example in the folds bordering the box.



  It is also planned to use sheets of various colors, in order to distinguish boxes of different dimensions. One can also consider printing indications on one or more of the faces, making it easier to identify the positioning of the boxes.



   It is of course possible to use, depending on the specific needs, a single box or several grouped, which can be fixed for example with a strapping by means of a plastic strip, as used in packaging.



  The above description relates to a parallelepipedic box, but it is of course possible without departing from the scope of the present invention to envisage other forms, for example a tubular box of triangular, circular, ovalized section, etc.



  We can plan to manufacture these boxes on request or in standard formats.



  As a variant, it is possible to envisage carrying out the interior filling with panels of honeycombed cartons or with an expanded material intended to harden after expansion. One could also use plastic plates or metal assemblies, possibly articulated.

Claims

1. Formwork box intended to create a recess in a concrete pour, characterized in that it comprises a box reinforced by a removable three-dimensional interior frame.

2. Box according to claim 1, characterized in that said box and / or said frame are arranged to be able to be packaged folded, so as to occupy a reduced volume, then deployed during their use.

3. Box according to claim 1 or 2, characterized in that the box is constituted by at least one cut in a plastic sheet.

4. Box according to claim 3, characterized in that said sheet is made of extruded polypropylene.

5. Box according to claim 3 or 4, characterized in that said cutting comprises fold lines marked at predetermined locations in order to delimit the walls (11 to 14, 16 and 17) of the box.

6.

Box according to claim 5, characterized in that the box further comprises a flange (15), intended to be fixed on the adjacent wall.

7. Box according to claim 5 or 6, characterized in that the box (10) comprises at least one opening wall (16, 17) provided with removable fixing means to the corresponding side walls (11, 12, 13).

8. Box according to claim 7, characterized in that said fixing means are constituted by flaps (18, 19) and / or fixing tabs (161, 171) provided on the edges of the opening wall and side walls corresponding.

9. Box according to claim 8, characterized in that said flaps (18, 19) are separated from the side walls by fold lines (181, 191), each flap comprising at least one slot (182, 192) capable of receiving said tabs (161, 171).

10.

Box according to claims 1 to 9, characterized in that it further comprises pre-perforated lines (121) capable of facilitating the tearing of walls to be removed.

11. Box according to claims 1 to 9, characterized in that the smooth outer wall has impressions so as to ensure the identification of the box.

12. Box according to claims 1 to 9, characterized in that the dimensions of the box correspond to predetermined standard dimensions.

13. Box according to claim 12, characterized in that different colors of sheet correspond to said standard dimensions.

14. Box according to claims 1 to 9, characterized in that several boxes are made integral by connecting means.

15.

Box according to claim 14, characterized in that said connecting means are constituted by a strapping by means of a band.

16. Box according to claim 1 or 2, characterized in that said three-dimensional interior reinforcement consists of plates (21, 22) of dimensions corresponding to the interior dimensions of the box and arranged transversely with respect to each other, in the deployed position of the frame.

17. Box according to claim 16, characterized in that said plates (21, 22) have, over half their length, slots (23, 24) intended to receive the corresponding plates, nested transversely.

18. Box according to claim 16 or 17, characterized in that said plates are made of cardboard.

19.

Method of manufacturing a formwork box according to claim 1 or 2, characterized in that the sheet or the elements constituting the box are cut from a sheet, the fold lines are marked, then the side walls are assembled by gluing , stapling or stitching, and the three-dimensional interior frame is assembled, while leaving the box and the frame flat, so as to occupy a minimum packaging volume.

20. A method of manufacturing a formwork box according to claim 19, characterized in that the box and the frame are deployed, the inner frame is introduced into the box, then the opening walls of the box are closed. .

21.

Use of a formwork box according to claim 1, to create a recess in a concrete pouring by means of a box reinforced by a removable internal frame, according to which the frame and the box are removed, after setting of the concrete, and reused.

22. Use of a formwork box according to claim 1, to create a recess in a concrete pouring by means of a box reinforced by a removable internal frame, according to which the frame is removed after setting of the concrete and left partially the box in place to form a sheath. 1. Formwork box intended to create a recess in a concrete pour, characterized in that it comprises a box reinforced by a removable three-dimensional interior frame. 2. Box according to claim 1, characterized in that said box and / or said frame are arranged to be able to be packaged folded, so as to occupy a reduced volume, then deployed during their use. 3. Box according to claim 1 or 2, characterized in that the box is constituted by at least one cut in a plastic sheet. 4. Box according to claim 3, characterized in that said sheet is made of extruded polypropylene. 5. Box according to claim 3 or 4, characterized in that said cutting comprises fold lines marked at predetermined locations in order to delimit the walls (11 to 14, 16 and 17) of the box. 6.

Box according to claim 5, characterized in that the box further comprises a flange (15), intended to be fixed on the adjacent wall. 7. Box according to claim 5 or 6, characterized in that the box (10) comprises at least one opening wall (16, 17) provided with removable fixing means to the corresponding side walls (11, 12, 13). 8. Box according to claim 7, characterized in that said fixing means are constituted by flaps (18, 19) and / or fixing tabs (161, 171) provided on the edges of the opening wall and side walls corresponding. 9. Box according to claim 8, characterized in that said flaps (18, 19) are separated from the side walls by fold lines (181, 191), each flap comprising at least one slot (182, 192) capable of receiving said tabs (161, 171). 10.

Box according to claims 1 to 9, characterized in that it further comprises pre-perforated lines (121) capable of facilitating the tearing of walls to be removed. 11. Box according to claims 1 to 9, characterized in that the smooth outer wall has impressions so as to ensure the identification of the box. 12. Box according to claims 1 to 9, characterized in that the dimensions of the box correspond to predetermined standard dimensions. 13. Box according to claim 12, characterized in that different colors of sheet correspond to said standard dimensions. 14. Box according to claims 1 to 9, characterized in that several boxes are made integral by connecting means. 15.

Box according to claim 14, characterized in that said connecting means are constituted by a strapping by means of a band. 16. Box according to claim 1 or 2, characterized in that said three-dimensional interior reinforcement consists of plates (21, 22) of dimensions corresponding to the interior dimensions of the box and arranged transversely with respect to each other, in the deployed position of the frame. 17. Box according to claim 16, characterized in that said plates (21, 22) have, over half their length, slots (23, 24) intended to receive the corresponding plates, nested transversely. 18. Box according to claim 16 or 17, characterized in that said plates are made of cardboard. 19.

Method of manufacturing a formwork box according to claim 1 or 2, characterized in that the sheet or the elements constituting the box are cut from a sheet, the fold lines are marked, then the side walls are assembled by gluing , stapling or stitching, and the three-dimensional interior frame is assembled, while leaving the box and the frame flat, so as to occupy a minimum packaging volume. 20. A method of manufacturing a formwork box according to claim 19, characterized in that the box and the frame are deployed, the inner frame is introduced into the box, then the opening walls of the box are closed. . 21.

Use of a formwork box according to claim 1, to create a recess in a concrete pouring by means of a box reinforced by a removable internal frame, according to which the frame and the box are removed, after setting of the concrete, and reused. 22. Use of a formwork box according to claim 1, to create a recess in a concrete pouring by means of a box reinforced by a removable internal frame, according to which the frame is removed after setting of the concrete and left partially the box in place to form a sheath.