Prefabricated formwork

Abstract: A prefabricated collapsible formwork module is assembled at a factory site, including the provision of a pair of sheathing panels (1,2) which can be made of insulating material, as well as the mounting of the vapor barrier (13), the filler strips (9), bearing blocks (4,5), and flexible or foldable connecting elements (3) extending between bearing blocks on the exterior surfaces of the panels extending between the panels to retain the panels when they are being erected. The sheathing panels may also have a waterproof membrane applied thereto, and the concrete reinforcement is assembled between the sheathing panels at the factory site. When the framework module is fully assembled, it is then collapsed, that is, by moving one sheathing panel against the other including sandwiching the foldable or flexible connecting elements and the concrete reinforcement which is preferably in the form of a grid, and the module can then be stored and transported to a building site. At the building site, the module is spread apart to the full extent of the connecting means and spacers are provided between the sheathing panels for maintaining the panels apart. Typical male (14) and female (13) plates are intercalated at the edges of the sheathing panels to form joints (24) with adjacent panels.

Description: The present invention relates to a prefabricated formwork for concrete and more particularly to a collapsible prefabricated form for concrete walls. The time-tested method of constructing concrete walls for buildings include the pouring of concrete into a formwork set up, in situ. This operation includes the erection of the form which includes a pair of vertical sheathing panels in a spaced relationship by means of connecting elements. such formwork is either of the removable and thus reusable type or is of a lost form type wherein the formwork becomes part of the structure after the concrete is cured. A lost form of formwork utilizing sheathing panels of insulating material is called generally an insulating formwork. All known insulating formwork comprise a connecting element which connects the two sheathing panels. This type of formwork can be devided into two main categories depending on the arrangement between the connecting elements and the sheathing panels. The first category may be referred to as a hollow parallelepiped blocks. In this category, one can find a connecting element which is molded with the sheathing at the factory site and is sometimes referred to by the trademarks ARGISOL and MARENGO. The advantages of this first category is that it is not necessaty to install the connecting elements at the building site since they are already molded at the plant or factory with the two sheathing panels. On the other hand, this type of formwork has serious disadvantages in terms of storage or transportation given the rather high volume/surface-of-formwork ratio. The second category is referred to as the planar solid slab formwork. In this category the connecting elements are normally rigid and are supplied separately from the sheathing panels which are in the form of the planar solid slabs. Examples of this category is shown in U.S. Patents 4,604,843 and 4,888,931 and Canadian Patent 1,233,042. The disadvantages of this category of formwork is that the connecting elements must be assembled at the building site which increases the installation cost of the formwork. The formwork of both of these categories is subject to other disadvantages at the on-site installation, and that is the relative small dimensions of the modules. For example in order to erect a 10 m 2 form one must assemble 10 to 40 modules on site, depending on the type of formwork used, which increases the number of joints and the cost of installation. As far as the fabrication of these modules is concerned, various elaborate machining or molding procedures are required in order that the edges of the modules form proper joints on assembly. Attempts to overcome these disadvantages have been made wherein the smaller modules are assembled at the factory site to form larger formwork sections and transporting these to the building site. In such a case one encounters transportation problems in view of the high volume to formwork surface ratio. That is a large volume of forms must be carried for a relatively small formwork surface. Each of the forms are of course spaced apart and held there by the ties such that one lands up transporting a great deal of air. On the other hand, once insulating formwork is being utilized, other tasks must be added such as the installation of reinforcement rods, vapor barrier, water proofing membranes, or filler blocks. These additonal tasks increase the installation costs and construction delays. DE-A-2 538 246 discloses a module in which, once collapsed, the panels are staggered. This requires space for storage or transportation. It is an aim of the present invention to provide formwork which can be rapidly installed and which takes the advantages of the above mentioned two categories of insulating formworks without the disadvantages. It is a further aim of the present invention to provide a prefabricated collapsible formwork which will reduce the amount of space required for storage or transportation as compared with the above prefabricated formwork. It is further aim of the present invention to provide a prefabricated formwork which includes vapor barriers, waterproof membranes, insulation, reinforcement and filler blocks already included at the plant site, thereby reducing the installation costs and construction delays at the building site. It is a further aim of the present invention to provide prefabricated formwork modules which are of a greater size than those considered in the above two categories. It is a further aim of the present invention to provide a prefabricated or preassembled collapsible formwork which one assembles at the building site and readies to receive concrete as well as the outside finish covering and the interior finish covering. As claimed, the invention proposes a prefabricated collapsible formwork module for molding a substantially vertical concrete wall comprising a first sheathing panel, a second sheathing panel and a plurality of connecting elements extending between the first and second sheathing panels in a spaced-apart position when the module is opened and the connecting elements are anchored to the first and second sheathing panels. According to the invention the formwork and connecting elements are constructed and assembled at a factory site remote from the building site such that during storage and transportation of the formwork modules, each formwork module is collapsed with the first and second sheathing panels adjacent one another and in transversal and longitudinal alignment with each other with the connecting elements (3) folded down in a more compact shape; upon extension of the connecting elements, the first and second sheating panels are in transversal and longitudinal alignment with each other and spaced-apart to the full extent of the connecting elements during assembly at the building site, the first and second sheathing panels including edges having respective male and female mating joint means for permitting the modules to be assembled with first and second panels in edge to edge relationship. As claimed, the invention proposes also a method of providing a prefabricated collapsible formwork module at a building site for forming vertical concrete walls, including the steps of selecting a first sheathing panel having edges, with at least one face being smooth, and a second panel having a configuration and dimensions similar to the first sheathing panel and having at least a smooth face, forming respective male and female mating joint means on the edges of said first and second panels for permitting modules to be assembled with first and second panels in edge to edge relationship attaching the first ends of a plurality of connecting elements to the first sheathing panel in a spaced apart relationship such that the connecting elements have opposite ends extending from the smooth face of the first panel, connecting the opposite ends of the connecting elements to the second sheating panel such that the smooth face of the second panel faces the smooth face of the first panel, collapsing the first and second sheating panels against each other for storage and transportation with the first and second sheating panels adjacent one another and in transversal and longitudinal alignment with each other with connecting elements folded down in a more compact shape, separating the first and second panels to the full extent of the connecting elements during the assembly at the building site, said first and second panels being in transversal and longitudinal alignment with each other upon extension of the connecting elements. In a more specific embodiment of the present invention there are provided bearing devices on the exterior of the first and second sheathing panels respectively and the connecting elements pass through the panels and are anchored to the bearing devices. In a still more specific construction, the bearing devices are in the form of a filler member and the sheathing panels are insulating panels. In a further specific embodiment, a concrete reinforcement in the form of a grid is assembled between the first and second sheathing panels at the factory site. Further, the vapor barrier and the waterproof membrane can be installed on the insulating sheathing panels at the factory site such that all of the component parts of the lost form can be preassembled at the factory site and the form can be collapsed for storage and transportation. The erection of the formwork at the building site consists of separating the first and second sheathing panels and by maintaining the separation by inserting spacers therebetween and connecting the male and female joints at the edges of the panels with adjacent panels. In a more specific embodiment the spacers could be foldable spacers which are preassembled at the factory site and which can be deployed at the building site when separating the first and second sheathing panels. The invention is especially concerned with the preassembling of as many building components as possible on the formwork, at the factory site, and to use as much as possible, conventional building materials in order to avoid the necessity of molding processes such as for molding expandable polystyrene. It is an aim therefore to render the form construction as universal as possible. Certain advantages which can be noted from the present invention include: Reduced storage and transportation costs since the form utilizes foldable connecting elements allowing the forms to be collapsed, thereby reducing their respective volume to formwork surface ratio; A rapid and simple assembly of the prefabricated panels, and in particular a larger size module when using insulating sheathing panels, thereby reducing the number of assembling steps on the building site and the number of joints for a given formwork surface. For example to erect 10 m 2 of formwork only three modules are required under the present invention instead of the current 10 to 40 modules. The prefabrication of the sheathing panels is simple since no molding or machining of the panels is required. All that is required is to drill holes through the sheathing panels. A new form mating joint is described which offers resistance to traction and compression and this in two or three perpendicular directions. The system allows for rapid assembling and in case of errors an equally rapid disassembling of the modules. Preassembling the vapor barriers, the waterproof membrane and the filler blocks, both interior and exterior, as well as the concrete reinforcement , at the factory site, eliminates having to provide for these steps at the building site, thereby reducing costs. Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration, preferred embodiments thereof, and in which: Fig. 1 is a fragmentary vertical cross-section of a formwork for a concrete frame building having a wooden exterior facing and a gypsum panel interior facing in accordance with the present invention; Fig. 2 is a fragmentary vertical cross-section of another embodiment of the present invention and showing a metallic exterior facing and a gypsum panel interior facing; Fig. 3 is a fragmentary vertical cross-section of still another embodiment of the present invention and showing a metallic exterior facing and a wood panel interior facing; Fig. 4 is a fragmentary vertical cross-section of still another embodiment of the present invention and showing an exterior stucco facing and an interior ceramic tile facing; Fig. 5 is a fragmentary vertical cross-section of still another embodiment of the present invention and showing an exterior brick facing and an interior gyspsum panel facing; Fig. 6 is a vertical cross-section of still another embodiment of the present invention and having a stucco facing on one side thereof and a ceramic tile facing on the other side thereof; Fig. 7 is a fragmentary elevational view of a further embodiment of the joint between two formwork modules; Fig. 7A is a horizontal cross-section taken along lines 18A-18A of Fig. 7; Fig. 7B is a fragmentary vertical cross-section taken along lines 18B-18B of Figs 7 and 7A; Fig. 7C is a view showing a detail of Fig. 7; Fig. 8 is a fragmentary cross-sectional view showing still a further embodiment of a connecting element in accordance with the present invention; Fig. 8A is a cross-sectional view similar to Fig. 8 showing the form in a different operative position; Fig. 8B is a fragmentary enlarged cross-sectional view taken along lines 23B-23B of Fig. 8A; Fig. 9 is a fragmentary cross-sectional view showing still a further embodiment of the connecting element of the present invention; Fig. 9A is a fragmentary elevational view taken along lines Q-Q of Fig. 9; Fig. 10 is a fragmentary cross-sectional view showing a still further embodiment of the connecting element of the present invention; and Fig. 10A is a cross-sectional view taken along lines 27A-27A of Fig. 10. Referring now to the drawings and in particular to Fig. 1, fragments of two forms joined together at a building site are illustrated wherein each form has an exterior sheathing panel 1 made of expanded polystyrene (EPS). An opposite interior sheathing panel 2 of similar insulating material is also shown. The exterior panel 1 and interior panel 2 are held together by flexible connecting elements 3. These flexible connecting elements 3 illustrated in the embodiment of Fig. 1 are made from multi strand metal cable. It is understood that the connecting elements can be made of other types of materials such as plastic. The connecting element 3 is anchored at the exterior of sheathing panel 1 by means of a bearing block 4 and at the interior sheathing panel 2, by a bearing block 5. These bearing blocks 4 and 5 can be fabricated out of wood having square outline and dimensions of 89mm x 89mm by 19mm. It is understood that these bearing blocks can also be made of metal, plastic, or other material having the necessary structure resistance and the shapes and dimensions could be different. The connecting elements 3 are passed through the panels 1 and 2 to be anchored in the bearing blocks 4 and 5 as shown in the drawings. These are assembled at the factory site so that the form is prefabricated before shipping. It is important that the connecting elements 3 be at least foldable so that the panel 2 can be collapsed onto the panel 1 for instance in the storage or transportation condition and then be expanded to the full extent of the connecting member 3 at the building site when it is being assembled. Another embodiment of the connecting elements is illustrated in Fig. 1 and this includes connecting elements 6 which are made up of a plurality of metallic monofilaments grouped together but spaced apart one from the other. These connecting elements are anchored to the respective sheathing panels 1 and 2 by means of bearing blocks 7 and 8 respectively, also illustrated in Fig. 1. The bearing blocks 7 and 8 as illustrated are made of wood as are the bearing blocks 4 and 5. However the bearing blocks 7 and 8 are much thinner than the blocks 4 and 5 in view of the fact that the connecting elements 6 include several spaced monofilaments anchored at different locations on the bearing blocks 7 and 8. In the case of connecting elements 3, they are anchored at one location and either of blocks 4 and 5. These bearing blocks 4 and 5, and 7 and 8 are considered discontinuous blocks. On the other hand, the exterior surfaces of the sheathing panels 1 are provided with continuous all-purpose filler strips 9. These blocks are strips 9 having in the present embodiment a thickness of 19mm and a width of 89mm. The filler strip 9 is used for nailing the exterior wooden facing 10 and has a support for the sheathing panel and referred to as a continuous bearing strip. A similar multi- purpose filler strip 11 is provided on the interior sheathing panel 2 and a connecting element 3 is anchored exteriorly to both filler strips 9 and 11. The filler strip 11 is used as a base for receiving screw-type fasteners for the interior gypsum panels 12 and for retaining the vapor barrier 13 13 which is mounted to the panel 2 at the factory site. Respective formwork modules are connected together at joint 24, that is at the edges of the respective sheathing panels 1 and 2. In the embodiment of Fig. 1 a male joint member 14 and female joint member 15 help to locate the panels at the joint 24. These elements 14 and 15 clearly can be made of wood as shown in the drawings or of metal or plastic or other combination of materials. The two sheathing panels 1 and 2 making up the form are held at a spaced-apart position against the connecting elements 3 by means of spacers. In Fig. 1, spacer 16 is placed therein at the building site during assembly. A string 17 is provided to remove the spacer 16 when it is no longer required. Spacer 18 is a permanent spacer installed in the form at the building site. The spacer 18 is shown with two notches for receiving reinforcement rods 19, and this combination is allowed to be lost in the concrete when it is poured. Another embodiment of the spacer is illustrated by the numeral 20. The spacer 20 includes a hinge 21 and a locking device 22 which locks the spacer 20 in its extended position when the form is installed at the building site. Spacers 18 and 20 are provided with plates 23 which are in contact with the interior faces of the sheathing panels 1 and 2. The concrete 25 is poured into place between sheathing panels 1 and 2. All of the components are preassembled at the factory site with the exception of spacers 16, 18 and 20 which are installed at the building site. The reinforcement rods 19, the concrete 25 and the gypsum panels 12, as well as the exterior wood facing 10 are installed at the building site. Referring now to Fig. 2 the external metallic facing 37 is fixed to metal filler strip 26. The filler strip 26 is a multi-purpose bearing strip that helps to support the exterior sheathing panel 27. The interior gypsum panels 28 are fixed to metallic filler strip 29 which is also a multi-purpose bearing strip which helps to support the interior sheathing panel 30 and which holds the vapor barrier 31 to the panel 30. The sheathing panels 27 and 30 are also held by the discontinuous bearing members 32 and 33. The bearing members 26, 29, 32 and 33 are connected by means of connecting elements 38 which are cables. The bearing blocks 39 and 40 are connected by connecting element 41 which is made up of a number of spaced-apart mono-filaments wires. The bearing elements can be made out of metal as shown in Fig. 2 or can be made out of other materials. The joints 34 are in the form of rabbet joints and the male joint elements also are bearing blocks as are the joint elements 36 to which a connecting element 38 is anchored. Prefabricated temporary spacers 42 which are installed at the building site are provided to maintain the two sheathing panels 27 and 30 in their spaced extended position at the building site. Spacer 42 is provided with a wire 43 for the purpose of removing the spacer when it is no longer required. The spacer is provided with a notch 44 to facilitate the installation thereof at the building site. The spacers 45 which also serves to separate the sheathing panels 27 and 30 are installed at the factory site and are deployed at the building site. The spacer 45 includes a mechanism provided with three hinges 46 and is provided with a blocking device 47. The concrete reinforcing structure 48 is assembled at the factory site in the form of a metallic trellis or grid. This grid 48 is parallel to the sheathing panels 27 and 30 and can be conveniently collapsed for storage and transportation when the panels 27 and 30 are collapsed against each other with the metallic grid work 48 sandwiched therebetween. When the forms are being assembled at the building site the reinforcing grid 48 is properly located in a spaced relationship with the help of the notches 49 provided in the spacers. At the joints of the various formwork modules, the metallic reinforcing grid is overlapped as shown at 50. Fig. 3 shows a similar formwork with an exterior sheathing panel 51 made up of a rigid insulating material, i.e. expanded polystyrene (EPS) as a core 52 sandwiched between reinforcement coatings 53 which can be a wood chip sheet on the exterior face and a polymeric reinforcement coating 54 on the interior surface of the panel 51. These coatings are of course provided at the factory site. The interior sheathing panel 55 is made up of a composite material including a core 56 and coatings 57 and 58 which are held together by a chemical adhesive or by mechanical fasteners. For example the core 56 can be an extruded polystyrene material while the coating 57 is a pressed wood fiber glued to the core 56 and the coating 58 is a two-ply plywood glued to the core 56. The external sheathing panel 51 and the internal sheathing panel 55 are connected by means of foldable connecting elements 59 which are rigid links connected by means of three hinges 60. The connecting element 59 is mounted to the sheathing panels 51 and 55 at the factory site along with the discontinuous bearing blocks 61 made out of plastic and the bearing blocks 62 made out of wood. The plastic bearing block 63 is connected to the wooden bearing block 64 by means of a flexible connecting element 65. The flexible connecting element 65 in this embodiment is made of a chain with metal chain links. The multi-purpose filler strips 66 serve as bearing blocks for the connecting elements 69 and also serve to receive screws for mounting the outer metallic facing 67. The filler strip 66 is attached to the filler/bearing block 68 by a foldable connecting element 69 which is made up of a metallic chain 70 and several metal cables 71 in spaced apart relationship. The interior facing can be in form of a stained wood panel 72 fixed to the wooden filler strip 68 which is also a bearing block for the internal sheathing panel 55. The form joints are shown as rabbet joints at the edges of the panels 51 and 55 and are provided with bearing block 73 made out of plastic which also serve as the male joint elements. The bearing block 74 also serves as the female joint element and this is made out of wood and mounted to the panel 55. The elements 62, 64, 68 and 74 also retain the vapor barrier 81. The spacing of the panels 51 and 55 is provided by a link-spacer 75 having hinges and blocking mechanisms. The link-spacer 75 can also serve as a connecting element and is anchored to filler members acting as bearing plates as shown in the drawings. This link-spacer 75 is mounted at the factory site and deployed at the building site. The concrete reinforcing grid is installed at the factory site and includes a grid pattern of rods welded at 78 or by mechanical fasteners 79. The joints of the reinforcing grid is formed at the factory site by providing hooks 80. All of the components are preassembled at the factory site with the exception of the metallic exterior facing 67, the stained wood finishing facing 72 and the concrete 82 which is poured in situ. Referring now to Fig. 4 the exterior sheathing panel 83 is composed of an insulating material such as expanded polystyrene (EPS) 84 and a reinforcement grid 85. The reinforcement grid 85 is attached to the insulating panel 84 by mechanical fasterners or by chemical adhesives and the assembly thereof is done at the factory site. The internal sheathing panel 86 is composed of a rigid insulating panel 87 attached to a wood-chip panel 89 by means cf mechanical fasteners 88. The vapor barrier 90 is installed at the factory between the layers 87 and 89. The two sheathing panels 83 and 86 are connected together by means of foldable connecting members such as chain 91. Connecting element 92 is in the form of rigid links articulated at hinges. The length of the flexible elements 91 or 92 can be adjusted. For instance the chain 91 or member 92 is coupled through a discontinuous retaining member having a deformable opening in one direction. The numeral 93 represents this device and allows the possibility of adjusting the distance between the two sheathing panels of this formwork. The connecting element 92 includes rigid links with hinges and has graduations 94 with weak points 96 in order to break off the length at preditermined lengths. The graduations 94 on the connecting element 92 can be coupled to a retaining device 95 having a deformable opening in one direction allowing the possibility of adjusting the length of the connecting element 92. The interior ceramic tiles facing 97 can be applied directly to the wood chip panel 89 with suitable glue or a mortar coating 98. The exterior facing 99 is made out of stucco reinforced with metallic slats 100. Spacing between the sheathing panels 83 and 86 is provided by means of the hinged spacer member 101 which is mounted at the building site. The concrete reinforcement is in the form of a metallic grid 102 maintained in place by means of the notches 103 on spacer 101. The joint of the grid is provided at the building site by allowing the overlapping of the grids at 104. The concrete is poured between the sheathing panels 83 and 86. As in other embodiments, all of the elements are preassembled at the factory site with the exception of the exterior and interior facings. Reference will now be made to Fig. 5 which shows an exterior sheathing panel 131 connected to the interior sheathing panel 122 by foldable connecting elements 123 which are of the flexible type. The sheathing panel 122 comprises a expanded polystyrene material (EPS) providing an insulated panel 124 covered with reinforcement coatings 125 and 126. The sheathing panel 131 is supported by two dimensional continuous support panel 127. This panel 127 can be made of a thin wood chip material or other similar material. The connecting element 123 is anchored to continuous bearing device 127 by mechanical anchors 128. The interior sheathing panel 122 is supported by a two dimensional continuous bearing panel 129. The vapor barrier 130 is retained by the panel 129. The interior facing is a gypsum panel and is fixed by means of a metal filler strip attached to the panel 129 at the factory site. The sheathing panel 131 and 122 are spaced apart by means of link spacers 136. The exterior facing 134 is of brick and is connected to the continuous support device 127 by means of masonry connectors. The concrete is poured in situ and is reinforced by means of the metal grid 135 which is preassembled at the factory site. Fig. 6 shows a sheathing panel 137 composed of a plastic grid 138, a wood chip panel 139 and a fiber board 140. The panel 137 is connected to the sheathing panel 141 by means of foldable connecting elements 142. The sheathing panel 141 is composed of a wood grid 143, a gypsum panel 144, and a rigid insulating panel 145. The grids 138 and 143 are assembled at the factory site with the connecting elements 142 and the link spacers 146. The other components are assembled at the building site according to specific requirements of each project and depending on the availability of the materials. The grids 138 and 143 are the primary bearing elements. These primary elements 138 and 143 can be of plastic or wood, such as indicated, or can be made of metal or other suitable material. The stucco 147 is reinforced by metal slats mounted to the sheathing panel 137. The ceramic tiles 149 are applied to the panel 141. The concrete is poured in situ and is identified by the numeral 150. The concrete is reinforced by means of reinforcement rods 151. Figs. 7, 7A, 7B, and 7C show a joint which provides for unlimited longitudinal movement along the axis of the joint because the bearing device 190 and the retaining member 182 extend along the length of the axis of the joint. The bearing device 183 is provided with a retaining means 184 which is coupled with the retaining device 182 to prevent against movement in the two transverse directions. With only light pressure, the retaining device 184 is opened and can be closed on the retaining member 182. The bearing devices 190 and 183 are connected to similar bearing devices on the other opposed sheathing panel forming the formwork by means of foldable connecting elements 185. After the sheathing panels 186 and 187 of the respective modules have been adjusted in the longitudinal direction any further movement is prevented by applying fastener 188 by use of a hammer, at the building site. The fastener 188 is applied to the bearing devices 190 and 183 respectively. The fastener is illustraded in Fig. 7C. The waterproof membrane 189 is made of asphaltic emulsion and is applied at the factory site on all of the exterior surfaces of the sheathing panels which are not in contact with the concrete. The insulating sheathing panel 186 and 187 are reinforced by means of a reinforcement layer 191. The reinforcement layer has adequate properties to receive the waterproof membrane of asphaltic emulsion. Refering now to Figs. 8, 8A and 8B, the insulating sheathing panel 239 is connected to a similar insulating sheathing panel 240 by means of a foldable connecting element 241 which is somewhat telescopic. The foldable connecting element 241 comprises a number of rigid elements of which one element can slide relative to the other. For example element 242 slides on element 243 by means of an eyelet 244 on the link 242. The course of movement is limited by the stop 245. The telescopic mechanism can be obtained by sliding one rigid element with respect to another as shown or it can be a mechanism which permits extension and contraction movement between the elements. The foldable connecting element 241 can be fabricated from a cylindrical metal rod such as shown. In its collapsed position the connecting element 241, in its telescopic mode as shown in Fig. 8, is contained within cavities 246. These cavities permit the formwork to be collapsed and occupy the minimum of volume during storage and transportation. Insulating sheathing panel 239 is retained by bearing blocks 247. A thermal break is provided by a layer of insulating material 248 provided over the end of the connecting element 241, thereby preventing a thermal bridge. Referring now to the embodiment shown in Figs. 9 and 9A, the insulating sheathing panel 263 and the insulating sheathing panel 264 are both connected together by means of a foldable connecting element 265. The connecting element 265 comprises a foldable section 266 made of a metal cable attached to a plug device 267 made of insulating rigid plastic and a metal device 268. The foldable section 266 is preferably a metal cable as shown. The insulating sheathing panel 263 is supported by a lost bearing device 269. The bearing device 269 can be fixed to the sheathing panel 263 by means of an adhesive coating 270 as shown or by other mechanical fasteners. The plug 267 is fixed to the bearing block 269. The insulating sheathing panel 264 is retained by the temporary bearing strip 271. The bearing strip 271 is called temporary since it can be removed and recuperated after the concrete has been cured. This element 271 can be utilized in other similar construction projects. The temporary bearing strip 271 can be a piece of wood 19mm x 89mm as shown or by other shape and material which is suitable. The element 271 will remain in good condition since no other work will be applied to this part. This is possible because the bearing strip 271 is maintained in place by the simple squeezing pressure exerted by the socket 268. The element 268 includes a jaw 272 which can be subjected to elastic deformation within a suitable limit. During the fabrication at the factory site, the jaw 272 is opened under pressure to introduce the bearing strip 271. After the pressure has been released the jaw 272 tightens against the block 271. The element 268 is retained in place by means of a bracket 273 and the configuration of the jaw 272. After the concrete has hardened the block 271 is removed from the jaw 272 by means of a hammer and can be reused. The use of the connecting element with the possibility of removing the bearing block will be very useful in many types of applications, especially where the concrete surface of the wall is to be decorative and including brick construction etc. Referring now to Figs. 10 and 10A, insulating sheathing panel 291 and insulating sheathing panel 292 are maintained in spaced apart position by means of a link spacer 293 which is assembled at the factory site. The link spacer 293 is an articulated connecting element which is provided with retaining means 294 and a blocking mechanism which includes a female element 295 and a male blocking element 296. The link/spacer 293 includes all the usual articulated link elements such as rigid sections 297, 298, 299, 300 and hinges 301. The sheathing panel 291 is retained by bearing block 302. The panel 292 is retained by the bearing block 303. The thermal break of the metalic parts is provided by means of insulating layers 304. The connecting element function can be removed and the spacer function of the piece 293 retained by eliminating elements 297 and 300 and the bearing blocks 302 and 303. The spacer can have the retaining element 294 which exert a pressure on the insulating panel during the deployment at the building site as shown. The connecting function can be provided by an anchor mechanism or by chemical adhesive or a combination of the two. The blocking mechanism of the spacer can be provided by a female blocking element 295 fixed on a rigid element and the blocking male element 296 fixed on another element as shown. Any other anti-rotation devices can also be used.

Claims: A prefabricated collapsible formwork module for molding a substantially vertical concrete wall comprising a first sheathing panel (1), a second sheathing panel (2) and a plurality of connecting elements (3) extending between the first and second sheathing panels in a spaced-apart position when the module is opened and the connecting elements are anchored to the first and second sheathing panels (1,2), characterized by the fact that the formwork and connecting elements (3) are constructed and assembled at a factory site remote from the building site such that during storage and transportation of the formwork modules, each formwork module is collapsed with the first and second sheathing panels (1,2) adjacent one another and in transversal and longitudinal alignment with each other with the connecting elements (3) folded down in a more compact shape, and in that, upon extension of the connecting elements, the first and second sheating panels (1, 2) are in transversal and longitudinal alignment with each other and spaced-apart to the full extent of the connecting elements (3) during assembly at the building site, the first and second sheathing panels (1,2) including edges having respective male and female mating joint means for permitting the modules to be assembled with first and second panels (1,2) in edge to edge relationship. A prefabricated collapsible formwork module as defined in claim 1, wherein the sheathing panels (1,2) are made of insulating material (51, 55). A prefabricated collapsible formwork module as defined in claim 1, wherein a vapor barrier (13) is preinstalled to one of the sheathing panels (1, 2)at the factory site. A prefabricated collapsible formwork module as defined in claim 1, wherein filler strips (9) are mounted to at least one of the sheathing panels (1, 2) on the exterior face thereof at the factory site. A prefabricated collapsible formwork module as defined in claim 1, wherein a concrete reinforcement (48) is provided between the sheathing panels (1, 2) at the factory site and is collapsible for storage and transportation with the sheathing panels (1, 2), the concrete reinforcement (48) being sandwiched therebetween. A prefabricated collapsible formwork module as defined in claim 1, wherein; a vapor barrier (130) and filler strips (133) are mounted on at least one of the sheathing panels (122) at the factory site while a concrete reinforcement (135) is located between the sheathing panels (122, 131) during the assembly at the factory site and is collapsible therewith as being sandwiched between the sheathing panels (1, 2). A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting elements (3) pass through the sheathing panels and are anchored at each end to bearing blocks (4, 5) located on the exterior face of each sheating panel (1, 2). A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting element is a multi-strand flexible metal cable (38). A prefabricated collapsible formwork module as defined in claim 7, wherein the bearing blocks (4, 5) are assembled on the sheathing panels (1, 2) at the factory site and the connecting elements are anchored to the bearing blocks at the factory site. A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting elements include a bunch of mono-filament flexible strands (6) individually spaced apart and individually, anchored to the bearing blocks (7, 8). A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting element comprises articulated link elements (297, 298, 299, 300). A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting element is a flexible chain(65) made up of chain links. A prefabricated collapsible formwork module as defined in claim 11, , wherein the connecting element includes a first rigid link member (297) including a head portion anchored to the bearing block (302) on the exterior of the first sheathing panel (291) and the first link member (297) extends through the width of the combined bearing block and the first sheathing panel (291), a first hinge means (301) is in the form of an eyelet at the end of the first link member (297) adjacent an inner surface of the first sheathing panel (291), a second link member (300) extends through the second sheathing panel (292) and includes a head anchored against the bearing block (303) on the exterior surface of the second sheathing panel (292) and a second hinge means (301) which includes an eyelet at the end of the second link member (300) adjacent the inner surface of the second sheathing panel (292) and a pair of rigid link members (298, 299) is hinged at the first and second eyelets (301) and include an eyelet (301) intermediate the pair of link members (298, 299) extending between the first and second eyelets (301) such that the pair of link members (298, 299) can fold against each other when the first and second sheathing panels (291, 292) are collapsed. A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting element (92) passes through the sheathing panels (83, 86) and is anchored at each end against bearing blocks (95) located on the exterior face of each sheathing panel (83, 86), wherein the connecting element (92) is a link member of adjustable length and at least one of the bearing blocks (95) is provided with a one way deformable bracket adapted to engage stop means (94) provided on the connecting element (92) and thereby anchor the connecting element at a desired length. A prefabricated collapsible formwork module as defined in claim 1, wherein the connecting elements (3) are flexible. A prefabricated collapsible formwork module as defined in claim 7, wherein at least one of the bearing blocks is in the form of a reusable strip (271) applied at the building site and the end of the connecting element (265) includes an open socket (272) for receiving the strip (271). A prefabricated collapsible formwork module as defined in claim 1, wherein a spacer (16) in the form of a rigid elongated member extends between the first sheathing panel (1) and the second sheathing panel (2) at the building site when the formwork module is being erected. A prefabricated collapsible formwork module as defined in claim 17, wherein the spacer (16) is prefabricated independently of the formwork module and is inserted between the first sheathing panel (1) and the second sheathing panel (2) only when the panels have been separated apart while being erected at the building site. A prefabricated collapsible formwork module as defined in claim 18, wherein the spacer is a rigid link member (18) with the bearing means fixed to each end thereof having a length corresponding to the space between the first and second sheathing panels (1, 2) when they are separated to an erected position at the building site. A prefabricated collapsible formwork module as defined in claim 18, wherein the spacer is a rigid member (20) having at least one hinge (21) allowing the spacer (20) to be folded for insertion or removal from between the first and second panels (1, 2). A prefabricated collapsible formwork module as defined in claim 1, wherein a spacer is provided between the sheathing panels and wherein the spacer (75) is a link-spacer (75) extending between the first and second panels (51, 55) respectively and the spacer (75) is preinstalled at the factory site. A prefabricated collapsible formwork module as defined in claim 4, wherein the filler strips (9, 11) are continuous wooden strips which also act as bearing blocks for the connecting elements (3) and the filler strips (9, 11) are mounted to the exterior surface of one of the sheathing panels (1, 2) at the factory site. A prefabricated collapsible formwork module as defined in claim 4, wherein the filler strips (9, 11) are in the form of an elongated plastic element and extend along the exterior surface of one of the sheathing panels (1, 2) and can act as bearing blocks for the connecting elements. A prefabricated collapsible formwork module as defined in claim 4, wherein the filler strip (66) is a metallic stamping or extrusion mounted at the factory site on the exterior surface of one of the sheathing panels (51) and can act as a bearing block for the connecting elements (69). A prefabricated collapsible formwork module as defined in claim 1, wherein the first and second sheathing panels (27, 30) each include edges having respective joint means (34) for permitting the modules to be erected one to the other in edge-to-edge relationship to make up the formwork, and wherein joint elements (34) in the form of male and female members extend along the length of the edges of contiguous panels and are adapted to be intercalated to form the joint and prevent lateral movement. A prefabricated collapsible formwork module as defined in claims 1 or 25, wherein joint elements (34) of male and female members extend along the length of the edges of the first and second sheathing panels (27, 30) and are adapted to be intercalated to form the joint (34) and prevent lateral movement. A prefabricated collapsible formword module as defined in claim 25, wherein retaining means (184) are provided to connect the joints (34). A prefabricated collapsible formwork module as defined in claim 7, wherein the bearing blocks are in the form of panels (127, 129) covering the exterior face of the sheathing panel (131, 122). A prefabricated collapsible formwork module as defined in claim 1, wherein the first or second sheathing panels (137, 141) may be in the form of a grid (138) to which further formed panels are added at the building site. A prefabricated collapsible formwork module as defined in claim 1, wherein the joints of contiguous panels are overlapped by joint elements (14, 35) extending along at least a portion of the respective edges. A prefabricated collapsible formwork module as defined in claim 1, wherein the first and second sheathing panels (27, 30) each include edges having respective joint means (34) for permitting the modules to be erected one to the other in edge-to-edge relationship to make up the formwork, and wherein joint elements (35) are provided on respective contiguous panels such that one joint element overlaps the joint to prevent lateral movement but the joint elements allow longitudinal sliding movement of the modules relative to one another along the joint axis. A prefabricated collapsible formwork module as defined in claims 30 or 31 wherein the joint means (34) includes a retaining means (184) to lock the joint in place once the modules have been assembled. A prefabricated collapsible formwork module as defined in claim 7, wherein the connecting member includes a first link member extending through a portion of the first sheathing panel (239) and including a head anchored against a bearing block (247) on the exterior surface of the first sheathing panel (239) the first sheathing panel including a cavity (246) to accommodate a portion of the first link member and a second rigid link member extending through a portion of the second sheathing panel (240) and including a head anchored against the bearing block on the exterior of the second sheathing panel (240) and the second sheathing panel (240) including a cavity (246) accommodating a portion of the second link member and a plurality of telescoping rigid link members (242, 243) extending between the first and second link members of the connecting element whereby when the module is being collapsed, the telescopic link members (242, 243) telescope within the cavities (246) formed within the first and second sheathing panels (239, 240). A method of providing a prefabricated collapsible formwork module at a building site for forming vertical concrete walls, including the steps of selecting a first sheathing panel having edges, with at least one face being smooth, and a second panel having a configuration and dimensions similar to the first sheathing panel and having at least a smooth face, forming respective male and female mating joint means on the edges of said first and second panels for permitting modules to be assembled with first and second panels in edge to edge relationship attaching the first ends of a plurality of connecting elements to the first sheathing panel in a spaced apart relationship such that the connecting elements have opposite ends extending from the smooth face of the first panel, connecting the opposite ends of the connecting elements to the second sheating panel such that the smooth face of the second panel faces the smooth face of the first panel, collapsing the first and second sheating panels against each other for storage and transportation with the first and second sheating panels adjacent one another and in transversal and longitudinal alignment with each other with connecting elements folded down in a more compact shape, separating the first and second panels to the full extent of the connecting elements during the assembly at the building site, said first and second panels being in transversal and longitudinal alignment with each other upon extension of the connecting elements.

Inventors: CHAGNON ALAIN, CHAGNON CLAUDE, CHAGNON LUC, CHAGNON ROBERT, CHAGNON SERGE, GOUPIL YVAN, PHAM TRUNG TRINH, CHAGNON, ALAIN, CHAGNON, CLAUDE, CHAGNON, LUC, CHAGNON, ROBERT, CHAGNON, SERGE, GOUPIL, YVAN, PHAM, TRUNG TRINH
Applicants: PHAM TRUNG TRINH, PHAM, TRUNG TRINH
Application year: 1991
Main classification: E04B2
IPC codes: E04B2