US20190234089A1

US20190234089A1 - Assembly of Foldable Tensegrity Modules

Info

Publication number: US20190234089A1
Application number: US16/300,092
Authority: US
Inventors: Frédéric Jamin; Jérôme Quirant; Julien Averseng; Stéphan Devic
Original assignee: Centre National de la Recherche Scientifique CNRS; Universite de Montpellier I; AxLR SATT du Languedoc Roussillon SAS
Current assignee: Centre National de la Recherche Scientifique CNRS; Universite de Montpellier I; AxLR SATT du Languedoc Roussillon SAS
Priority date: 2016-05-12
Filing date: 2017-05-12
Publication date: 2019-08-01
Also published as: EP3455433A1; ES2787381T3; FR3051207A1; CA3023781A1; WO2017194775A1; FR3051207B1; EP3455433B1

Abstract

The invention concerns a method for assembling a set of foldable/unfoldable tensegrity modules, each comprising a plurality of bars (10), a plurality of nodes (40) allowing the articulation of the bars (10), the method being characterised in that it comprises: juxtaposing the modules such that two adjacent modules comprise nodes positioned one over the other in a vertical plane; linking said nodes of the two adjacent modules by means of a tension cable and support beam link; positioning cover elements extending between successive modules.

Description

FIELD OF THE INVENTION

The invention relates to the field of tensegrity structures.
It proposes in particular a mechanical assembly forming a support (platform for example) of the type with a foldable tensegrity structure.
In particular, it finds advantageous application in the development of temporary structures for access to sites such as tourism sites or swimming areas.

PRIOR ART

Despite awareness by public authorities intending to improve the suitability of tourism sites for persons with reduce mobility, it is noted that in certain regions, the seacoast remains difficult of access for this type of user. In fact, many tourism sites do not propose any structure allowing fully autonomous access for swimming.
Currently, access to the ocean for a person with reduced mobility can be accomplished by the use of a specific floating wheelchair which requires outside aid.
For autonomous access, there exist fixed structures (www.unfauteuilalamer.com), but they impact, by definition, the installation site.
In certain regions subjected to obligations regarding the defense of the environment, non-temporary installations are not viable solutions. For example, certain laws aiming to protect the coast impose a structure that can be disassembled and transported, having no permanent anchoring element in the ground, and which must allow the site to be returned to its initial state at the end of the concession.
Temporary structures such as floating pontoons that can be disassembled exist (www.belrive.fr/), but these remain poorly suited to seacoasts for reasons of stability, because they require considerable anchorage. Moreover, the load capacity is relatively small with regard to the volume occupied in the disassembled state, limiting their versatility.
Also known are modular solutions for forming platforms which can be disassembled, based on scaffolding components. These modular scaffolding systems allow the implementation of any type of platform capable of supporting considerable loads, on point supports. The components must however be adapted so as not to have considerable overweight. The point supports can be numerous and must be individually adjusted. The assembly of a structure implements separate components requiring a large number of operations; such solutions are therefore constraining in installation time and in labor.
There exists therefore a need for placing a lightweight, versatile installation with a low environmental impact, easily deployable and designed for temporary use.
Publication WO2005/111343 describes a deployable structure which can be assembled with other similar structures to form an installation such as a platform. However, such installations, based on the assembly of identical elementary cells, do not offer flexibility in terms of assembly, thus the cells cannot have different dimensions. Moreover, the placement of installations requires a large number of cell assemblies.
Also known are installations based on tensegrity structures.
Tensegrity is the facility of a structure stabilize itself through the interplay of forces of tension and compression which are distributed in it and achieve equilibrium within it. Structures established in a state of tensegrity are therefore stabilized, not by the resistance of each of their constituents, but by the distribution and the equilibrium of the mechanical stresses in the totality of the structure.
Thus, a mechanical system including a discontinuous system of compressed components within a continuum of tensioned components can find itself in a state of stable equilibrium. Which means, for example, that by connecting the bars using cables, without connecting the bars together directly, it is possible to constitute a rigid system.
For this reason, a tensegrity structure is a reticulated spatial system, the stiffness and stability of which arise from the combination of compression in the bars and tension in the cables.
Publication FR 2823287 describes a tensegrity system in the form of a reticulated structure with self-constraints of its various components, to achieve light construction structures of the type of a framework, panel or other similar assembly. However, this publication does not describe the notion of modularity, of assembly of tensegrity structures to form temporary platforms in poorly accessible zones in particular.
Such structures have the advantage of being particularly light and therefore easy to place. They are particularly suited for environments which it is desired to preserve.
The document “Les systèmes de tenségrité déployables: application à l'accessibilité de la baignade en mer [Deployable tensegrity systems: application to the accessibility of bathing in the sea]” (J. Averseng, F. Jamin, J. Quirant—Rencontres universitaires de Génie Civil, May 2015—https://hal.archives-ouvertes.fr/hal-01167613/document) describes a grid tensegrity structure, foldable and un-foldable, composed of a set of bars and of nodes connected to one another. The different nodes and bars of this structure are contiguous.
This structure has the advantage of being deployable on site and to allow the implementation of stable, light and reusable platforms.
Even so, it is complicated to handle and to place when it is desired to create platforms with large dimensions.
There exists, therefore, a need for a mechanical assembly forming a support (platform for example) of the type with a foldable tensegrity structure which allows the implementation of structures of large dimensions and which is easy to assemble or disassemble.

PRESENTATION OF THE INVENTION

A general goal of the invention is to propose a mechanical assembly forming a support of the type with a foldable tensegrity structure which does not have the disadvantages of the tensegrity assemblies of the prior art.
Another goal of the invention is to propose a mechanical assembly with a foldable tensegrity structure which is particularly adapted to the implementation of structures with large dimensions.
Yet another goal is to propose a mechanical assembly with a foldable tensegrity structure which is easy to assemble and disassemble, and in particular less costly in labor and in installation time.
Another goal of the invention is also to propose a mechanical assembly forming a support of the type with a foldable tensegrity structure which is versatile, easy to assemble and disassemble and easy to transport.
Another goal, also, is to propose a structure which—while still having excellent mechanical properties—does not require durable anchorage elements in the ground, is light and has a low environmental impact.
According to one aspect, the invention proposes a mechanical assembly with a tensegrity structure,
characterized in that

- it comprises at least two modules with a foldable/un-foldable tensegrity structure each comprising a plurality of bars and a plurality of nodes to which the bars are articulated;
- nodes of the same module being, when said module is deployed, distributed over two parallel planes and connected two by two by a connection element in tension perpendicular to said planes, each module including at least one assembly edge node situated in one of the two planes and without an opposite member in said module in the other plane, this node being adapted to be positioned in line with an assembly edge node of another adjacent module and to be connected to it by a connection element in tension or in compression perpendicular to the planes of the nodes of these two modules,
- and in that nodes of the upper plane of the two modules include coupling elements adapted for attachment,
- to several nodes of the assembly edge positioned along the same assembly edge and belonging alternately to one and the other of the two adjacent modules,
- to cover elements, or support elements designed to support said cover elements.

According to yet another aspect, it also proposes a support structure which includes a mechanical assembly of the aforementioned type of which several modules are deployed and disposed so as to be adjacent, each of these modules including at least one assembly edge node which is positioned in line with an assembly edge node of another adjacent module and which is connected to it by a connection element in tension or in compression perpendicular to the planes of the nodes of these two modules, said structure also including cover elements extending between successive modules.
Mechanical assemblies and structures of this type are particularly suited for the implementation of temporary structures, such as the scenic space catwalk type.
The invention also proposes a method for mounting such a support structure.

DESCRIPTION OF THE FIGURES

Other features, aims and advantages of the present invention will appear upon reading the detailed description that follows, with reference to the appended figures, given by way of non-limiting examples and in which:

FIG. 1 shows schematically a foldable-un-foldable structural module of a mechanical assembly conforming to an embodiment of the invention.

FIGS. 2A and 2B show schematically the disposition of nodes, respectively in an upper and lower layer of a structural module.

FIG. 3 illustrates the detail of a tensioning element.

FIG. 4 illustrates the detail of a node of an upper layer.

FIG. 5 shows a structural module in the folded state.

FIG. 6 illustrates a means of base adjustment of the node of a module.

FIG. 7 illustrates a means of attaching cover to a node by means of support beams.

FIG. 8 illustrates a solution for the implementation of cover formed of floor slats on support beams, of a system of guardrails and of access by stairs.

FIG. 9 shows schematically a module and its top view.

FIGS. 10a and 10b are representations of, respectively:

- on the one hand (FIG. 10a ), of nodes of the upper layer of an example of an elementary structural module with a 4×4 mesh and an associated set of bars
- on the other hand (FIG. 10b ), of a mechanical assembly conforming to an embodiment of the invention, assembling different structural modules of the type of those illustrated in FIG. 10 a, with a platform the cover of which is formed of floor slats resting on two sides on beams attached to the nodes;

FIGS. 10c and 10d are representations illustrating other examples of structural modules and of a mechanical assembly created by the assembly of these modules.

FIG. 11 illustrates the assembly zone between two modules.

FIG. 12 illustrates the assembly of two modules of different heights

FIG. 13 shows a platform made from the assembly of four structural modules.

FIGS. 14 and 15 are representations in perspective view and in exploded view of another solution for the implementation of cover.

FIGS. 16 and 17 illustrate the representation of a mechanical assembly conforming to another embodiment of the invention (FIG. 17), assembling different structural modules (FIG. 16—Column A) with a platform of which the cover is formed of plates pressed by their corners directly on nodes (FIG. 16, column C) and a set of stilts (FIG. 16—column B) on the border.

FIG. 18 illustrates in a perspective view an example of an assembly of two modules of the type of that in FIGS. 14 to 17

FIG. 19 illustrates modules in perspective view corresponding to different possible dimensionings.

FIGS. 20a and 20b illustrate the mode of attachment of the cover plates on the nodes.

FIG. 21 illustrates a solution for the implementation of cover formed from plates, of a system of guardrails and of access by stairs.

DETAILED DESCRIPTION OF AT LEAST ONE EMBODIMENT OF THE INVENTION

With reference to FIG. 1, a foldable-un-foldable structural module is shown. Each module is broken down in to structures called “tensegrity,” i.e. a reticulated structure formed of a discontinuous network of compressed bars interacting within a continuous network of tensioned cables, the whole being stabilized by an initial constraint state. This principle is analogous to inflatable systems, formed of a compressed medium (air or other fluid) in equilibrium with a shell in tension.
As illustrated in FIG. 1, a structural module of this type includes a set of bars 10 corresponding to the compressed elements, of tensioned cables 20 and of tensioners 30 connecting a set of nodes 40.
More generally, cables and/or tensioners can be replaced by any element allowing a tension connection: chains, straps, etc. . . .
The module comprises the assembly of two parallel horizontal layers of nodes 40. Thus, represented by, respectively, FIGS. 2A and 2B, is the disposition of the nodes 40 in a lower layer 2 and in a upper layer 3. In each of the layers, the nodes 40 are connected by a network of layer cables 20 a.
The topology of the module, representing the assembly of layers 2 and 3, is inspired by weaving: a network of compressed elements, formed of sub-assemblies of bars 10 alternately connecting nodes 40 of one layer to another, mirrors the warp and weft threads which form fabrics.
The peripheral cables 20 b and 20 c situated at the periphery of the module also allow the connection of the two layers 2 and 3 by connecting the nodes 40 at the periphery of the module, alternately, from one layer to the other.
The peripheral cables 20 b are said edge cables; they connect the nodes 40 of the lower layer 2 to the node 40 of the upper layer 3, said nodes being position on one side of the module.
The peripheral cables 20 c are said corner cables; they connect nodes 40 of the lower layer 2 to the node 40 of the upper layer 3, said nodes being positioned on two consecutive sides of the module.
The edge cables 20 b and the corner cables 20 c can have different inclinations.
With respect to the plane of the layers, the cables 20 a have a generally horizontal inclination, the peripheral cables 20 b and 20 c, a diagonal orientation, and the cables with turnbuckles 30 a vertical orientation.
The bars 10 can be made of a metallic material such as aluminum, or of a metallic alloy. Other types of materials are possible, such as wood, plastic (PVC for example), composite (glass, carbon fiber, fibrous concrete, . . . ). The nodes 40 are preferably made of a high-strength material such as steel. The cables 20 and the tensioners 30 are also preferably made of steel; they can also be made of fibrous materials.
The compressed assemblies 10 are also assembled by means of elements called “tensioners” 30, passing between the nodes 40 of each layer 2 and 3, and which allow stiffening the structure of the module. The “interior” tensioners 31, shown in FIG. 1, allow localized initial forces to be generated while the “edge” elements 32 have an impact on all the peripheral elements.
Thus, with reference to FIGS. 1, 2A and 2B, the nodes 40 a of a layer situated at the periphery of the module are connected by layer cables 20 a to an adjacent node 40 b of the same layer and by peripheral cables 20 b and 20 c to two other nodes 40 b of the other layer.
The other types of nodes 40 b, the interior nodes of a layer, have a node 40 b of the other layer opposite in the same vertical plane, orthogonal to the layers. Thus, these nodes are connected to 4 other nodes 40 of the same layer by layer cables 20 a, and by a tensioner 30 to an opposite node 40 b of the other layer.
The tensioners 30 between two nodes 40, illustrated in detail in FIGS. 3 and 4, consist of an assembly of cables attached to each node, with a turnbuckle 33 connecting the cables 34 and 35 of the opposite nodes 40.
The cable and turnbuckle assembly 30 advantageously allows controlling the tension of the cables. With respect to another element which could for example be a threaded rod, cables with turnbuckles allow tension to be released while still keeping the tensioning elements attached to the nodes 40, thus facilitating the deployment of the module. Moreover, these elements also allow a lighter structure to be obtained.
A node 40 can also include a coupling element 41 allowing the attachment of the tensioners 30. This element is advantageously a means of attachment of the ring type disposed on a lower face of a node 40 of the upper layer 2 and on an upper face of a node 40 of the lower layer 3.
The nodes 40 of the lower and upper layers can be identical. In this configuration, the nodes 40 of the lower layer 3 are turned 180° with respect to the nodes 40 of the upper layer 4.
The release of tension by the turnbuckles 31, also allows, during folding of the module, to control the orientation of the nodes 40 for optimized stowage of the bars in the folded state.
The connection between the bars 10 (nodes 40) allows the folding-unfolding of a module from a bundle, illustrated in FIG. 5, contiguous, light, compact and easily transportable, thus facilitating the phases of assembly and disassembly with little labor. Moreover, the structure allows minimizing the phases of adjustment by the placement of turnbuckles 31.
The operation of folding/un-folding the structural module is allowed by the configuration of the nodes 40, which include means of articulated attachment 46 of the bars 10, illustrated in FIGS. 3 and 4.
These means are typically 1 or 2 in number, and can be of the pivot connection type, or of the ball joint type. The nodes 40 can combine the two types of articulation. Lightness and the folding characteristic facilitate handling. Moreover, the nodes 40 allow optimally compact stowing (contiguous parallel bars 10).
Modules of all dimensions (shapes and heights) in space can be generated within the limits of their portability, for example according to standard NF X35-109 relating to the load carried by workers in France. For this reason, the limit of weight to be handled during working activities for one person is a maximum of 30 kg.
Thus a typical module, as shown in FIG. 1, comprises 30 nodes, connected by a set of 24 bars.
The dimensions, such as the height or the mesh (spacing between the nodes 40 of the same layer) can be adjusted at will depending on the dimensions of the elements which are selected accordingly. For example, the dimensions of a module can typically be 4 m×4 m, the height being adjustable from 0.5 to 1.50 m depending on the selected inclination of the bars 10.
Two modules having the same mesh can be distinguished by their height. Thus, for a given mesh, the height of the modules is determined by varying the length of the cables with turnbuckles 30, the length and the inclination of the peripheral cables 20 b and 20 c, and of the bars 10.
As illustrated in FIG. 4, the nodes 40 include a plurality of lateral openings 42 allowing the passage of cables 20 connecting the nodes 40 of the same horizontal layer. Typically, these lateral openings 42 are 4 in number, two first openings 42 being situated in the same plane as the bars connected to the node 40. The two other openings 42 are disposed in a plane orthogonal to the plane of the bars 10.
In one embodiment, each cable 20 is attached between two nodes 40. In another embodiment, the cables 20 pass through the nodes 40, and said nodes 40 include a system, such as sleeves, allowing a portion of the force of the cables 20 to be transmitted to the nodes 40.
By the use of cables 20, 34 and 35 as tensioned elements the structure naturally offers a certain visual transparence, but also with respect to the actions which affect the elements, such as swell in a context of semi-submersion at the edge of the sea. Moreover, the cables 20, 34 and 35 are elements which make the system very light, by optimizing the use of the constitutive material, and therefore the mass, so that strictly necessary with respect to stiffness and mechanical strength.
The structural module has the possibility of not resting on the ground directly by means of the nodes.
Thus, as illustrated in FIG. 6, certain nodes 40 of the lower layer can include base elements 43. A base element 43, for example an adjustable foot attached to the lower face of a node 40, allowing adjustment of the height of the structural module. This can ensure a stable structure despite a limited number of ground support points (which remains a function of the operating load to be taken up); thus typically a module includes 4 ground support points.
Due to its lightness and its stiffness, the implantation on the ground requires a reduced number of support points, which perturbs the environment very little. Difficult and sensitive sites can be made accessible by a platform. The occupation of the site can be only temporary, disassembly allowing a return to the initial state.
Moreover, the adjustable height base elements 43 allow the flatness of the system to be easily adjusted.
With reference to FIG. 7, the design of the nodes 40 allows the placement of cover elements so as to form a platform structure. For this purpose, the node 40 also comprises, in one embodiment, protruding coupling elements 44 suitable for the attachment of support beams 50 as illustrated in FIG. 7.
This attachment is accomplished by an element including a groove which engages by sliding, like a rail mechanism, on the upper portion of a node 40 of the upper layer.
The coupling element 44 is for example in the form of a cylinder with a collar on its top on the upper portion of a node 40 allowing an element, such as a support beam 50 comprising a groove of complementary shape, typically a T-shaped groove, to engage by sliding in said upper portion of the node 40. The support beam element 50 is positioned on at least two adjacent nodes 40, perhaps three or more.
The support beam element 50 also includes on its upper face a portion having a T-shaped profile allowing the engagement of an element including a complementary groove.
To allow the attachment of the cover, it is possible for example to use a junction bar 51 which is embedded in the support beam element 50. The junction bar 51 allows, on either side of it, to attach the installation of floor slats 52. The latter are interlocked by their widths between the support beam 50 and the junction bar 51.
In another embodiment, the features of the support beams 50 and the junction bars 51 can be combined into a single beam positioned over at least two adjacent nodes 40, perhaps three or more, and comprising a specific section allowing, among other things, the attachment of the cover.
The coupling element 44 therefore offers the installation of cover 52 by their widths between two rows of adjacent nodes 40 each including a junction bar 51.
FIG. 8 shows a structural module used for the implementation of a platform formed of floor slats 52 carried by support beams 50. In this configuration, the support beam 50 can also be used for the attachment of spandrel beams 53 disposed at the ends of the cover. It is possible to superimpose other elements on the spandrel beams 53, of the type such as a guardrail 54, stairway 55, access ramp (not shown), canopy (not shown), thus allowing the implementation of versatile structures.
FIG. 9 illustrates a module and its schematic top view.
As shown, the bars 10 are disposed in parallel rows 11, and in parallel rows 12 perpendicular to said rows 11.
The peripheral nodes 40 a (including a single connection to a bar 10) disposed at the ends of the rows of bars 11, define two sides 13 of the module.
Likewise, at each end of the rows of bars 12, two sides 14 of the module are defined.
The sides 13, 14 are therefore defined by an assembly of peripheral nodes 40 a connected by cables 20, disposed in the same vertical plane, orthogonal to the rows of bars 11, 12, to which these nodes 40 are connected.
In the lower part of the figure, the peripheral nodes 40 a have been represented by solid circles (black nodes), while the interior nodes (nodes 40 b) have been represented by hollow circles (white nodes).
For each side 13, 14, the number of nodes 40 a in the high position is determined, therefore belonging to the upper layer, and the number of nodes 40 a in the low position, therefore belonging to the lower layer.
When the number of nodes 40 a in the high position is in the majority, the side is called “+”; in the reverse case, the side is called “−.”
The elementary structural module illustrated in FIG. 10a is a structural module with a 4×4 mesh with, at its upper part:
two nodes with “+” ends;
a single node with “−” ends.
Shown on the right portion of the same figure is a network of support beams 50 used on these nodes.
These beams are all mutually parallel and extend in a direction Δ1 connecting one and the other of the two nodes of the “−” ends. In the figure, the direction Δ2 is perpendicular.
The assembly of modules with identical structure, as shown in FIG. 10 b, is accomplished by juxtaposing, end to end, a “+” side of a module with a “−” side of another module. This assembly allows the modules to be placed in correspondence in a complementary manner; an edge to edge assembly is therefore obtained where the nodes 40 a of the upper and lower layers are placed opposite respectively the nodes 40 a of the lower and upper layers of the other structural module.
In the case where structure modules of the type of those of FIG. 10a are used, the assembly is accomplished under the following conditions:

- Condition C1: any edge parallel to Δ1 corresponds to an end of the “+” type of its module and includes two support nodes on its upper layer;
- Condition C2: the connection between two modules is accomplished by the alignment of 3 nodes: one node of a “−” end of one of the modules and two nodes of a “+” end of the other module; the placement and attachment of a beam on the nodes thus aligned ensures assembly, as well as on the other nodes of the modules and the stiffening of the structure obtained;
- Condition C3: a module of which the “−” ends are parallel to Δ1, at least one of these ends constituting an edge of the assembled structure, is practicable provided that said module is flanked by two other modules which allow the support of said edge. The nodes 40 a of the different modules being identical (in principle) and provided that the modules have an identical spatial geometry in the positioning of the nodes, the modules are connected together by means of the system with a turnbuckle to connect the opposite nodes 40 a. On their assembly edges, at least one node 40 a of the upper layer of a first module is connected by the turnbuckle system with a node 40 a of the lower layer of a second module, the two nodes 40 a being opposite.

More generally, a module with a given mesh structure (spacing between the nodes 40 of a layer) can be assembled edge to edge with another module having the same mesh structure. Thus, the two modules can be assembled along an edge having complementary nodes between the two modules (the nodes 40 a of the upper and lower layers of a module being placed opposite respectively the nodes 40 a of the upper and lower layers of the other structural module). In the case of FIGS. 10a and 10 b, the assembled modules are all identical (in this case, 4×4 mesh modules). Modules with different meshes can also be assembled together. That is what FIGS. 10c and 10d illustrate. The dimensions of the elementary structural modules can in fact be varied within the limits of their weight, which must be compatible with portability.
The assembly of several modules edge to edge also allows, in a simplified manner less costly in labor, the implementation of platforms with multiple architecture (for example, FIGS. 10b and 10d ).
Moreover, modules of different heights can be combined to adapt to the morphology of the terrain. The structure of the module and the arrangement of the nodes 40 thus offers great flexibility with regard to possible implementation (see for example FIGS. 10c and 10d ).
The assembly of different modules can also be stabilized and reinforced by the installation of cover elements between the different structural modules.
FIG. 11 shows the installation of cover elements on the nodes 40 a of two modules juxtaposed edge to edge.
The installation of a support beam 50 is therefore carried out, as described previously, on the coupling elements 44 of the nodes 40 a, the support beam preferably rests on at least 2, perhaps 3 nodes 40 a.
The assembly side has in the same vertical plane an alternation of nodes 40 a of the first and second module, the support beam 50 therefore rests on at least one node 40 a of the upper layer of the first module and one adjacent node 40 a of the upper layer of the second module, which has the advantage of stiffening the assembly.
Thus, the connection between different structural modules can be carried out, on the one hand thanks to tensioners 30 between the complementary nodes 40 a of the modules, and on the other hand by cover elements which allow reinforcing and ensure the stability of the assembly.
These connection elements also allow limiting the number of ground supports of the assembled structure. In FIG. 11, the possibility is illustrated for the module M1 to be supported on two points on the ground 43 which belong to the module, and at a third point by the junction with the adjacent module M2. The module M1 which arrives at the junction with a single node 40 a at the lower portion is supported on the adjacent module M2 by suspension using a turnbuckle. The module M2 which has two nodes 40 a in its lower portion at the junction can be supported on the ground at four points 43, and supports the adjacent module M1 by its node 40 a in the upper portion. Said module M1, by connection with the turnbuckle 33, is therefore supported on the module M2.
For this reason, the assembly of two modules will rest on 6 ground supports, the assembly of three modules, 8 supports, etc. The number of ground supports of an assembled structure thus remains limited.
FIG. 12, illustrates the assembly of modules M1 and M2 of different heights. The modules differ by the dimensions of the cables with turnbuckle 30, and by the dimensions and inclination of the peripheral cables 20 b, 20 c and of the bars 10. The dimensions of the cables 20 are identical in the two modules. Thus, the assembly between the two modules is possible because they comprise the same meshing in the horizontal plane (spacing between the nodes 40 of a layer). This identical meshing allows the nodes 40 a of the module M1 to be made to correspond with the nodes 40 a of the module M2.
FIG. 13 illustrates the implementation of a platform by the assembly of a plurality of modules M1 to M4. Said modules can have different dimensions. Said platform includes 10 ground supports by means of base elements 43.
Thus, the simple addition of elementary modules, which can have any dimensions of length, width and height, allows different spatial configurations to be implemented.
The advantage of using modules in the repetitiveness of assembly by connection of nodes 40 a that are complementary from one module to the other. Unlike elementary cells, the monolithic structures of which are formed by adding structural elements step by step, the system according to the invention accomplishes a monolithic structure with a reduced number of structurally independent modules, with variable shapes and heights and geometrically complementary.
The structure thus composed has the benefit of a certain advantage in terms of robustness because a local failure remains limited to the module concerned.
Each module forms, in the folded state, a contiguous bundle, easily transportable and storable in a reduced volume and, in the deployed state, a rigid structure supporting a delimited cover and being able to receive many independent pieces of equipment (guardrails, stairs, ramps, etc.).
Depending on the dimensioning of the bars and of the cables, justifiable by a simple calculation code, each module is limited to a mass of 40 kg and can take up operational loads up to 500 kg/m²which is required for example in the case of bleachers which can be disassembled.
Thus, the structure satisfies two often opposed constraints: lightness and mechanical performance.
The shape of the modules allows, by juxtaposition and connection, the constitution of a monolithic structure with pathways of any length and with varied spatial configurations.
In a coastal zone, the bearing structure can be implanted in semi-submersion so as to constitute a platform of suitable height allowing accessibility to swimming areas and the practice of nautical activities with full autonomy. The system being light, its impact on the environment and on the implantation site is essentially nil, this being restored to its original state after disassembly.
FIGS. 14 and 15 illustrate another possible solution for the implementation of a cover, based on the elementary foldable/un-foldable module M.
This structure consists of a tensegrity grid M, a set of stilts 101 and a set of cover plates 102 applied to the structure.
The tensegrity grid M is a conventional grid formed from bars 110 corresponding to the compressed elements, of connecting elements in tension (tensioning cables, etc.) 120 connecting a set of nodes 140 on which the bars 110 are articulated so as to be foldable/un-foldable.
The stilts 101 are of two types: edge stilts 101 a and corner stilts 101 b.
Edge stilts 101 a are vertical stilts which extend between an edge node 103 b of the lower layer of the elementary module M and the corresponding edge node 140 e of the upper layer of the same elementary module M, distinct from a corner node (node 140 c) of said structure.
The corner stilts 101 b consist of two bars 104 b and 105 b which extend in a V shape from the same corner node 103 in the lower layer.
This node 103 is vertically opposite to a node 140 b immediately adjacent to a corner node 140 c, these nodes being added to the upper layer so as to offer 4 support points to the cover plates in this zone.
One of the bars (bar 104 b) extends vertically between the node 103 and the node 140 b.
The other bar (bar 105 b) extends obliquely between the node 103 and the corner node 140 c.
It thus ensures the taking up of a vertical force with respect to the corner node 140 c.
Two cables 106 a and 106 b extend horizontally between the nodes 140 b and 140 c, and between 140 b and 140 d, ensuring the taking up of horizontal forces with respect to the corner node 140 c.
Different structural modules (support grids) are of course possible for a cover of the plate type as shown in FIG. 16. They must however have meshing equal to or greater than 3×3.
Column A) of FIG. 16 gives several examples of modules, while column B) illustrates the addition of stilts and the addition of support nodes at the edge.
For its part, column C illustrates the cover implemented by means of plates supported on the nodes by their four corners.
FIG. 17 shows the edge to edge assembly on modules of the minimum size (3×3), the upper nodes of each module being completed in alternation. FIG. 18 illustrates an assembly accomplished from two elementary modules M1 and M2 of the type of module M illustrated in FIGS. 14 to 16.
In this assembly, the corner stilts of the two elementary modules M1 and M2 are eliminated, only the edge stilts 101 a subsisting in this plane.
The corner stilts 101 b are also retained, at the corners of each of the two elementary modules M1 and M2, in the other edge planes (perpendicular planes).
FIG. 19 illustrates for its part different types of meshing for the elementary structural module: 4×4 (M4×4 ), 3×3 (M3×3), 3×6 (M3×6) or with variable meshing (Mv on a 3×6 structure).
In the structure that has just been described, the support beams are not necessary. The cover elements—which in this case are plates—are supported directly on the nodes, which include coupling elements adapted for this purpose.
FIGS. 20a and 20b illustrate an attachment mode of the cover plates on the nodes.
In this means of attachment—which is given here only by way of an example—the nodes 140 each comprise several spurs (four in this case) to receive the corners of the plates 102. After the placement of the plates, a retaining cap 106 is applied above the node 140 at the intersection of four plates, on the upper face thereof, and is screwed to said node 140.
Such structures allow better interfacing during the placement of the cover.
FIG. 21 shows a structural module used for the implementation of a platform formed of plates 102 carried by nodes of the upper layer. In this configuration, the edge and corner nodes can also be used for the attachment of other elements, of the type such as a guardrail 54, stairway 55, access ramp (not shown), canopy (not shown), thus allowing the implementation of versatile structures.

Claims

1. A mechanical assembly with a tensegrity structure,

comprising,

at least two modules with a foldable/un-foldable tensegrity structure each comprising a plurality of bars and a plurality of nodes to which the bars are articulated;

nodes of the same module being, when said module is deployed, distributed over two parallel planes and connected two by two by a connecting element in tension perpendicular to said planes, each module including at least one assembly edge node situated in one of the two planes and without an opposite member in said module in the other plane, this node being adapted to be positioned in line with an assembly edge node of another adjacent module and to be connected to it by a connection element in tension or in compression perpendicular to the planes of the nodes of these two modules,

and wherein nodes of the upper plane of the modules including coupling elements adapted for attachment,

to several nodes of the assembly edge positioned along the same assembly edge and belonging alternately to one and the other of the two adjacent modules,

to cover elements, or support elements designed to support said cover elements.

2. The assembly according to claim 1, including at least one support beam for receiving a cover element, said beam being designed to be attached to several successive nodes belonging alternately to one and the other of the two adjacent modules, said nodes including protruding coupling elements for the attachment of said support beam.

3. The assembly according to claim 1, including a set of stilts designed to be placed under the nodes of the upper plane of the modules.

4. The assembly according to claim 1, including a tension connector comprising a turnbuckle connecting two cables attached by means of attachment rings to nodes positioned in line one above the other.

5. A support structure comprising the mechanical assembly of claim 1 of which several modules are deployed and disposed so as to be adjacent, each of these modules including at least one assembly edge node which is positioned in line with an assembly edge node of another adjacent module and which is connected to it by a connection element in tension perpendicular to the planes of the nodes of these two modules, said structure also including cover elements extending between successive modules.

6. The support structure according to claim 5, comprising one or more support beams slipped onto protruding coupling elements which are carried by the nodes of the modules.

7. The support structure according to claim 6, comprising junction bars of floor slats attached to support beams.

8. The support structure according to claim 7, comprising a plurality of floor slats disposed between two parallel rows of successive nodes and wherein said floor slats are engaged on each lateral end between a junction bar and a support beam attached to each of said rows of successive nodes.

9. The support structure according to claim 5, comprising spandrel beams attached along at least one side of one or more module(s), on the coupling elements of the nodes.

10. The support structure according to claim 5, wherein the cover elements are plates coupled to the nodes of the modules.

11. The support structure according to claim 10, comprising a set of stilts designed to be placed under the nodes of the upper plane of the modules.

12. The support structure according to claim 11, comprising edge stilts which extend vertically in line with nodes distinct from the corner nodes of the module.

13. The support structure according to claim 11, comprising corner stilts of which at least a portion extends between a corner node of the upper plane and a node of the lower plane vertically opposite to a node immediately adjacent to said corner node in said upper plane.

14. The support structure according to claim 5, comprising guardrails and/or ramps or access stairs attached to nodes.

15. A method of assembling a support structure according to claim 5, including the following steps:

juxtaposition of foldable/un-foldable tensegrity modules each comprising a plurality of bars, a plurality of nodes allowing the articulation of the bars, so that two adjacent modules include end nodes positioned one above the other in a vertical plane;

placement of a connection element in tension or in compression between said end nodes of two adjacent modules;

placement on the modules of cover elements or support elements designed to support said cover elements.