FR2889550A1 - Permanent formwork formation module for masonry field, has semi-cross-bars distributed on back side of rectangular panel, and with proximal bore receiving assembling screw and emerging out at level of front side of panel - Google Patents

Abstract

The module has a set of semi-cross-bars (20) distributed on a back side (5) of a rectangular panel (3) by extending perpendicular to the panel. The semi-cross-bars are placed in four rows parallel to an upper edge of the panel. Each semi-cross-bar has a male and/or female embedding element at the level of its distal end for engagement in a complimentary embedding element of a corresponding semi-cross-bar during the assembly of the module with another module. The semi-cross-bars have a proximal bore (22) receiving an assembling screw and emerge out at the level of a front side (4) of the panel. An independent claim is also included for a permanent formwork element comprising two identical modules embedded with each other at the level of their semi-cross-bars and assembled by a set of screws engaged by a set of screws engaged in proximal bores of embedded semi-cross-bars.

Description

The present invention relates to the technical field of masonry

concrete pool walls.

  It is known to produce reinforced concrete pool walls using lost formwork elements as described in patent application FR 2 790 777. Thus, it is proposed to make each formwork element lost by the assembly of two identical modules made of plastic. Each module then comprises a rectangular panel having a front face and a back face and a series of half-spacers distributed on the back side of the panel extending perpendicularly to the panel. In order to allow an assembly of the two modules together, each half-spacer comprises at its distal end a male and / or female interlocking element intended to engage in a complementary interlocking element of a half spacer. corresponding. Finally, the irreversibility of the assembly is obtained by welding the two half-spacers at the interlocking elements.

  Such a piece of lost formwork has the disadvantage of imposing a weld at each junction between the half-spacers. However, given the distribution of the half-spacers, this welding can be achieved only manually, which induces a relatively high manufacturing cost. In addition, it is not possible to guarantee perfect reproducibility of the welds so that the latter do not always have optimum strength and may yield during the injection of the concrete into the formwork element, which induces structural disorders in the wall in progress. On the other hand, if, in order to reduce labor costs, it is chosen to weld at only some of the demistines, then the lost formwork element is likely to deform locally under the pressure of the concrete. so that the resulting wall does not have perfect flatness.

  Thus, it appeared the need for a new type of module for the realization of a formwork element whose implementation is likely to ensure a perfect mechanical strength of the formwork element to prevent the risk of rupture and to obtain a perfectly flat wall at least at the face intended to be inside the pool.

  In order to achieve this objective, the invention relates to a module intended to be assembled with another identical module to form a lost formwork element for the realization of a concrete pool wall. According to the invention, this module comprises: a rectangular panel having a front face and a back face, a series of half-spacers distributed on the back side of the panel extending perpendicularly to the panel, each half-spacer comprising at the level of its distal end a male and / or female interlocking element intended to engage in a complementary interlocking element of a corresponding half-spacer when assembling two modules.

  In addition, according to the invention, this module is characterized in that at least some of the half-spacers comprise a proximal bore which is intended to receive an assembly screw and which opens at the front face of the panel.

  The invention also relates to a lost formwork element for the production of a pool wall which comprises two identical modules according to the invention nested one inside the other at their demientretoises and assembled by a series of screws engaged in proximal bores of nested half-spacers.

  The implementation of the screws for assembling the constituent modules of the lost formwork element provides a lost formwork element having a very high mechanical strength and in particular a high rigidity of its panels preventing any deformation of the latter under the effect of concrete pressure. In addition, the screw connection can be achieved without other tools that a screwdriver or an electric screwdriver while offering a very high quality of assembly so that the assembly of the modules can be performed by a low-skilled staff or by the end user of the lost formwork element who may be a simple handyman. Thus, the implementation of a screw connection makes it possible to envisage delivery of the unassembled modules, which allows a reduction in the selling price but also the storage volume of the modules before implementation and assembly. Indeed, it is possible to store before assembly the two constituent modules of a lost formwork element so that the distal end of the half-spacers of a module is in contact with the reverse side of the panel of the other module so that the assembly thus formed has a footprint smaller than that of the formwork element whose two constituent modules have their half-spacers nested at their distal ends.

  It should be noted that according to the invention, some only demientretoises may have a proximal bore. However, in a preferred embodiment all half-struts will have a proximal bore.

  According to a feature of the invention and to prevent oxidation of the threaded end of the screw, the proximal bore extends over only a portion of the length of the half-spacer. This advantageous characteristic of the invention makes it possible to avoid the appearance of spots at the level of the sealing liner placed in contact with the wall made by means of lost formwork elements according to the invention.

  In the same direction and in order to facilitate the introduction of the assembly screws, according to another characteristic of the invention, each demientretoise comprising a proximal bore comprises a distal bore which is coaxial with the proximal bore and which opens at the of the distal end of the half-spacer. This characteristic of the invention makes it possible to avoid having to perforate by means of the screw an excessive thickness of material. The proximal and distal bores are then separated by a solid intermediate zone.

  Preferably, the proximal bore has a length less than or equal to one quarter of the length of the half-spacer measured between its distal end and the back side of the panel while the distal bore has a length less than or equal to half the length of the half-strut and greater than a quarter of the length of the half-stretcher.

  According to a feature of the invention, a portion of the wall of the distal bore is intended to form a hooking zone for the thread of an assembly screw. This feature of the invention reduces the forces required for screwing while ensuring the effectiveness of the anchoring of the net.

  Still in the sense of greater ease of installation of the screw while ensuring the strength of the assembly, the distal bore has a proximal portion whose diameter is greater than the maximum diameter of the thread of the screw. assembly and a distal portion whose diameter is smaller than the maximum diameter of the thread of the assembly screw.

  According to another characteristic of the invention, the proximal bore has a proximal portion whose diameter is greater than the maximum diameter of the thread of the assembly screw and a distal portion whose diameter is smaller than the maximum diameter of the thread of the screw. assembly. This feature of the invention reduces the length on which it is necessary to screw the screw while leaving a portion at which the thread hangs so as to facilitate the engagement of the screw in the solid area at the level of bottom of the proximal bore.

  According to another characteristic of the invention intended to facilitate the pouring of concrete into the shuttering element obtained from the assembly of two modules according to the invention, each half-spacer comprises three ribs located at 120 from each other and a rib is oriented towards an upper edge of the module, the ribs of the half-spacer being intended to reinforce the latter and to provide a breaker and baffle function during the casting of the concrete.

  According to another characteristic of the invention intended to facilitate the implementation of the shuttering element obtained by the assembly of two modules according to the invention, the front face of the panel of each module comprises at least one cutting line for to guide a user for a panel cut of the module.

  In order to reduce the obstacles to cutting the panel, the demientretoises are then preferably arranged so as not to be on a cutting path defined by a cut line.

  According to another characteristic of the invention and to allow a cohesion at the right angles of walls made by means of lost formwork elements according to the invention, the front face of the panel comprises at least one cutting line located nearby. a side edge of the panel and intended after cutting the panel to define a concrete passage opening between two shuttering elements forming a right angle.

  According to yet another characteristic of the invention, the lateral edges as well as the upper and lower edges of the panel comprise interlocking means intended to allow the interlocking of two adjacent or superposed formwork elements.

  A module according to the invention can be made of any suitable material and preferably, in order to reduce its weight and its manufacturing cost, it will be made of injected plastic such as for example polypropylene or polyethylene.

  As has been said above, the invention also relates to a lost formwork element obtained by assembly by means of screws, identical modules according to the invention.

  According to a characteristic of the invention, the two modules are assembled by means of screws which each have a length greater than 1.3 times the length of a half-spacer with an unthreaded portion, which is heard from the head of the screw over a length greater than or equal to the length of a half-spacer and having beyond the unthreaded portion a self-tapping thread and whose self-tapping thread is engaged in the wall of a distal bore and / or in the solid area of the demientretoise of the module located opposite the head of the screw.

  Furthermore, in order to make it possible to obtain a lost formwork element of which at least one face is smooth, the heads of the assembly screws are preferably all located on the face of the same module.

  In addition, in order to avoid an oxidation liable to stain the waterproofing coating that can be applied against the wall obtained by means of a lost formwork element according to the invention, the threaded end of each assembly screw does not open into the proximal bore of the corresponding half-spacer.

  Of course, the various characteristics, mentioned above, modules or lost formwork elements according to the invention can be implemented with each other in different combinations when they are not exclusive of each other.

  Furthermore, various other features of the invention will emerge from the description given below with reference to the accompanying drawings which show, by way of non-limiting examples, a preferred embodiment of a lost formwork element and its modules. constituent parts according to the invention.

  Fig. 1 is a cross section of a lost formwork element according to the invention.

  Fig. 2 is a perspective in front view of a module for producing the lost formwork element illustrated in FIG. 1.

  Fig. 3 is a side perspective view of the module shown in FIG. 2.

  A lost formwork element according to the invention, as illustrated in Figure 1 and generally designated by the reference 1 has a generally parallelepipedal shape. The lost formwork element 1 is intended to be associated with other identical elements to define, for example, the formwork of a vertical wall of a swimming pool. The lost formwork elements 1 are then nested in each other vertically and laterally depending on the height and the desired wall length.

  Each shuttering element 1 is obtained by assembling two identical modules 2 made of injected plastic material. As shown more particularly in FIGS. 2 and 3, each module 2 comprises a rectangular panel 3 which has a front face 4 visible in FIG. 2 and a back face 5 visible in FIG.

  In order to allow a nesting of lost formwork elements 1 superimposed, the panel 3 has at its upper edges 6 and lower 7 interlocking means which, according to the illustrated example, comprise, on the one hand, at the the lower edge 7 a series of tabs 8 separated from each other by notches 9 and, secondly, at the upper edge 6 a series of fingers 10 extending perpendicular to the back side 5 being aligned with the notches 9. According to the illustrated example, the fingers 10 are separated from each other by a distance d substantially equal to the thickness e of a lost formwork element 1.

  In the same way, in order to allow an interlocking of juxtaposed lost formwork elements 1, the panel 3 has as a means of interlocking at its left and right lateral edges 11 a lateral tongue 13 located at the bottom of the left edge 11 and in the upper part of the right edge 12. It should be noted that the lateral tongues 13 also assume a function of limiting seepage of concrete at the junction of two formwork elements.

  In order to keep the panels 3 of the modules 2 constituting the lost formwork element 1 at a distance to define the receiving volume of the concrete, each panel 3 comprises a series of half-spacers 20 distributed on the back side 5 while extending perpendicularly to the panel 3. Each half-spacer 20 has at its distal end, opposite the panel 3, a male and / or female interlocking element 21 intended to engage in a complementary interlocking element. corresponding half-spacer when assembling two modules 2. According to the illustrated example, the half-spacers 20 are arranged in four rows parallel to the upper edge 6 of the panel 3 and the half-spacers of the same rank present alternately at their distal ends a male conformation and a female conformation so as to avoid errors in the assembly of two identical modules 2. It should be noted that according to the illustrated example the half-spacers 20 are arranged symmetrically with respect to a median plane P perpendicular to the panel 3.

  In order to allow an assembly of two modules 2 together, each demientretoise 20 comprises a proximal bore 22 which is intended to receive an assembly screw V and which opens at the front face 4 of the panel 3. The bore 22 is qualified as proximal because of its position relative to the panel 3. The bore 22 does not extend over the entire length e of the half-spacer 20 so that it is non-traversing. Preferably, the proximal bore 22 has a length e22 less than or equal to one quarter of the length e of the half-spacer 20. In order to have to pierce by means of the assembly screw V an excessive thickness of material , the half-spacer 20 also has a distal bore 23 which is coaxial with the proximal bore 22 and which opens at the distal end of the half-spacer 20. The distal bore 23 does not open into the bore proximal 22 so that it is separated from the latter by a solid zone 24. Preferably, the distal bore 23 has a length e23 less than or equal to half the length e of the half-spacer 20 and greater than quarter of the length e of the half-spacer 20.

  For the production of a lost formwork element 1, two identical modules 2 are used as described above. The demientretoises 20 of the two modules are nested one inside the other at their distal end and then an assembly screw V is engaged at each of the proximal bores 22 of the front face 4 of one of the two modules 2 of so that the front face of the other module provides a substantially smooth surface adapted to receive a sealing coating.

  Each assembly screw V will be chosen so as to have a length ev greater than 1.3 times and preferably equal to 1.5 times the length of a half-spacer e with a non-threaded portion extending from the head of the screw over a length greater than or equal to the length of a half-spacer e. Each assembly screw V will furthermore have beyond the unthreaded portion a self-tapping thread.

  In order to facilitate the penetration of the assembly screw V into the solid portion 24, the proximal bore 22 has close to its bottom a catching area for the thread of the assembly screw V. Preferably, the proximal bore 22 will be made to have a proximal portion whose diameter is greater than the maximum diameter of the thread of the assembly screw and a distal portion whose diameter is smaller than the maximum diameter of the thread of the assembly screw V. to ensure the effectiveness of the assembly achieved by the assembly screw V, a portion of the wall of the distal bore 23 is intended to form a fastening zone for the thread of the assembly screw V. Preferably, the distal bore 23 then has a proximal portion whose diameter is greater than the maximum diameter of the thread of the assembly screw and a distal portion whose diameter is smaller than the maximum diameter of the thread of the assembly screw. . Thus, the thread of the assembly screw is hooked into the distal portion of smaller diameter of the distal bore 23 of the half-spacer 20 located opposite the head of the assembly screw V. The presence of a larger diameter portion at the bores 23 reduces the effort required to install each screw assembly V. After the establishment of all the assembly screws V, the Lost formwork element 1 thus obtained has a particularly high mechanical strength and is therefore perfectly adapted to withstand the internal pressure exerted by the concrete during casting.

  In order to ensure optimum rigidity to the lost formwork element 1, each half-spacer 20 is preferably reinforced by three ribs 25 located at 120 from each other and a rib is oriented towards an upper edge of the module. The ribs of each half-spacer 20 then provide additional reinforcing function and during casting a guiding function, breeze motte and baffle concrete. In the same direction, the back side 5 of the panel also has stiffening ribs 26.

  Moreover, in order to facilitate the implementation of the lost formwork element and its adaptation to the different configurations that may be encountered, the front face 4 of each module 2 has a series of cutting lines 30 to 33 for guide a user for a panel cutout of the module. In order to guarantee easy cutting, the half-spacers are preferably arranged so as not to be on a cutting path defined by a cutting line.

  These cutting lines make it possible to fulfill different functions. Thus, the cutting line 30 makes it possible to produce an opening for placing a part to be sealed for receiving a submerged projector. The cutting lines 31 allow the realization of an opening for the establishment of a suction mouth of the water. The cutting lines 32 located near a side edge of the panel 3 are intended after cutting the panel to define a concrete passage opening between two shuttering elements forming a right angle. And finally the cutting lines 33 are intended to allow the realization of openings for the introduction of nozzles.

  Of course, various modifications may be made to the module 2 or to the lost formwork element 1 according to the invention without departing from the scope thereof.

Claims (17)

  1 - Module intended to be assembled with another identical module to form a lost formwork element for the realization of a concrete pool wall, module comprising: a rectangular panel (3) having a front face (4) and a a reverse side (5), a series of half-struts (20) distributed on the back side (5) of the panel extending perpendicular to the panel, each half-spacer (20) comprising at its distal end an element of male and / or female interlocking intended to engage in a complementary interlocking element of a corresponding half-spacer during the assembly of two modules, characterized in that at least some of the half-spacers (20) comprise a proximal bore (22) which is intended to receive an assembly screw and which opens out at the front face of the panel.   2 - Module according to claim 1 characterized in that the proximal bore (22) extends over only a portion of the length (e) of the half-spacer (20).   3 - Module according to claim 1 or 2 characterized in that each demientretoise (20) comprising a proximal bore (22) comprises a distal bore (23) which is coaxial with the proximal bore and which opens at the distal end of the half-spacer (20).   4 - Module according to claim 3 characterized in that the proximal and distal bores are separated by a solid intermediate zone (24).   5 - Module according to claim 3 or 4 characterized in that the proximal bore (22) has a length (e22) less than or equal to one quarter of the length (e) of the half-spacer measured between its distal end and the on the back (4) of the panel and in that the distal bore (23) has a length (e23) less than or equal to half the length (e) of the half-spacer and greater than one quarter of the length (e ) of the half-spacer.   6 - Module according to one of claims 3 to 5 characterized in that a portion of the wall of the distal bore (23) is intended to form a hooking zone for the thread of an assembly screw ( V).   7 - Module according to one of claims 3 to 5 characterized in that the distal bore (23) has a proximal portion whose diameter is greater than the maximum diameter of the thread of the assembly screw and a distal portion whose diameter is less than the maximum diameter of the thread of the cap screw.   8 - Module according to one of claims 1 to 7 characterized in that the proximal bore (22) has a proximal portion whose diameter is greater than the maximum diameter of the thread of the assembly screw and a distal portion whose diameter is less than the maximum diameter of the thread of the cap screw.   9 - Module according to one of claims 1 to 8 characterized in that each half-spacer (20) comprises three ribs (25) located at 120 from each other and a rib is oriented towards an upper edge of the module, the ribs of the half-spacer being intended to reinforce the latter and to provide a breaker and deflector function during the pouring of concrete.   10 - Module according to one of claims 1 to 9 characterized in that the front face (4) of the panel comprises at least one cutting line (30) for guiding a user for a cutting module panel.   11 - Module according to claim 10 characterized in that the demientretoises (20) are arranged so as not to be on a cutting path defined by a cutting line (30).   12 - Module according to claim 10 or 11 characterized in that the front face (4) of the panel comprises at least one cutting line (32) located near a side edge of the panel and intended after cutting the panel to define a opening passage of concrete between two formwork elements forming a right angle.   13 - Module according to one of claims 1 to 11 characterized in that the side edges (11,12) and the upper (6) and lower (7) of the panel (3) comprise interlocking means (8). , 9, 10, 13) intended to allow the interlocking of two adjacent or superposed formwork elements.   14 - Module according to one of claims 1 to 13 characterized in that it is made of plastic.   - Lost formwork element for the realization of a pool wall characterized in that it comprises two identical modules (2) according to one of claims 1 to 14 nested one into the other at their half. spacers (20) and assembled by a series of screws (V) engaged in proximal bores (22) of interlocked half-spacers.   16 - lost formwork element according to claim 15 characterized in that the two modules which constitute it are assembled by means of screws (V) which each have a length (Iv) greater than 1.3 times the length (1) of a half-spacer with a non-threaded portion extending from the head of the screw over a length greater than or equal to the length of a half-spacer and having, beyond the unthreaded portion, a self-tapping thread and the self-tapping thread is engaged in the wall of a distal bore and / or in the solid area of the half-spacer of the module located opposite the head of the screw.   17 - lost formwork element according to claim 15 or 16 characterized in that the heads of the assembly screws (V) are all located at the front face of the same module.   18 - lost formwork element according to claim 17 characterized in that the threaded end of each screw assembly (V) does not open into the proximal bore of the corresponding half-spacer.