EP1284324B1 - Device and process for fastening a building element and a cable structure and suspension bridge having such devices - Google Patents

Abstract

The fixing comprises a rigid casing (2) connected to and partially surrounding the cable harness. A deformable wedging structure (3) is located between the cable and the casing. Force transmission means (4,13,14) exert a longitudinal compression force parallel to the cable on the wedging structure. The wedging structure is pressed against the cable and the casing under the compression force so as to offer resistance to the movement of the casing and the cable harness. Independent claims are included for a fixing method and a suspended bridge.

Description

The present invention relates to the field of the use of cables in construction works.

It finds an application whenever it is necessary to retain a construction element with respect to a structural cable, or the structural cable with respect to the construction element, so as to avoid their relative movements parallel to the cable direction.

The term "structural cable" as used herein also covers a bundle or group of individual cables substantially parallel to each other, each individual cable may itself be composed of one or more elementary strands. The cable, or the individual cables, can be bare or individually sheathed, or consist of a mixture of these two types. The cable may optionally be contained generally in an outer protective sheath filled with an adherent material. In the case of a cable formed by a group of individual cables, they may be in direct contact with each other, or be spaced from each other.

The invention can in particular be implemented in suspension bridges comprising one or more load-bearing cables to be immobilized with respect to certain elements (pylon tops ...), and to which certain other elements must be attached (suspension of the apron, portions in solidarity with the apron ...).

The invention can also be applied in the field of prestressing, the structural cable then consisting of a cable tensioned to exert prestressing forces on a concrete structure or other, and to which certain elements of the structure can be set.

In the fixing zone, the interface that the cable presents to its environment is most often defined by generatrices essentially parallel to the longitudinal direction. Under these conditions, to prevent relative longitudinal movements between the cable and the element, it is necessary to exert on the cable a transverse clamping force to obtain sufficient friction at the interface.

This clamping can be obtained by means of corner jaws, in particular to achieve the anchoring of the structural cable. In the case In the case of a multi-strand cable, the jaws are installed individually around the strands, which implies that they can be separated from each other, a condition which is not always fulfilled in practice.

Otherwise, the clamping is usually carried out using collars having two shells (or more), biased towards each other by means of bolts or the like. The inside of the shells have a shape corresponding to the outer interface of the cable possibly completed by filling inserts.

This way of proceeding leads to an inhomogeneous transmission of the tightening forces on the section of the structural cable, even if it is possible to combat this disadvantage by a suitable filling of the inside of the collar (see EP-A-0 789 110 ). Depending on the periphery of the cable, the areas close to the intervals separating the shells tend to be less stressed than the others. As a result, in order to obtain a nominal clamping value, an excess of clamping must be applied in an undesirable manner for the reliability of the device and the good resistance of the cable. Along the cable, the collar transmits maximum force at the bolts, which must then be multiplied if the collar is relatively long. On the other hand, the application of transverse clamping stresses on the shells requires that they have a robust structure and a consequent thickness, which gives a relatively large mass to the fixing device.

In the German patent 869,977 , it has been proposed to secure the attachment of a suspension line to the cable carrying a suspension bridge by adding wedge-shaped jaws at both ends of a collar consisting of several shells tight against each other by bolts. This securing is quite relative since the wedge effect is largely lost in case of loss of tightening of shell assembly bolts due to creep or fatigue. In addition, the distribution of clamping forces is poorly controlled in case of tightening of these bolts. On the other hand, this device has the problems of size and weight usually posed by this type of collars.

Another disadvantage of the collar described in the German patent 869,977 is that the tightening is done by moving the jaws towards each other parallel to the cable. This results in a significant friction on the surface of the cable, especially annoying that the inner face of the jaws must be rough to grip the cable. This is already problematic with bare metal strands, and clearly unacceptable when the cable or its strands components are coated with a plastic sheath.

An object of the present invention is to provide a method of attachment which distributes well the forces transmitted to the structure cable.

The invention thus proposes a device for fastening between a construction element and a structural cable comprising a rigid housing connected to the construction element and surrounding the cable, a wedging structure comprising at least one deformable elastomer material, disposed between the cable and the housing, and force transmission means arranged to exert a longitudinal compressive force, parallel to the cable, on the wedging structure. The jamming structure is pressed against the cable and the housing under the action of the longitudinal compressive force, so as to offer resistance to movement of the housing and the construction element parallel to the cable.

The cable is gripped by the friction resulting from the orthogonal contact pressures generated by the longitudinal compression of the structure contained between the rigid outer casing and the cable passing therethrough.

The force transmission means make it possible to control the good holding of the binding and the precise positioning of the casing with respect to the cable. A minimum compression force may be applied before the final assembly of the device, or during this assembly before loading.

The wedging structure must naturally have sufficient resistance to compression and shear. Its longitudinal displacement during the application of the compression results in a uniform radial clamping of the cable.

The homogeneous transmission of forces at the interface between the wedging structure and the cable is facilitated by the fact that the wedging structure undergoes a certain deformation at the moment when the force transmission means exert the controlled longitudinal compression.

This deformation is due to the intrinsically deformable nature of all or part of the wedging structure housed between the housing and the cable. This structure may comprise an elastic material, a granular material, a fibrous material, or a mixture of such materials, and it may be made in one or more pieces. It has the property of expanding in the direction or directions orthogonal to the compression direction or directions, either by intrinsic elastic movement or by the movement of the individual particles (fibrous and / or granular) with respect to one another or compared to a binder. The deformable structure has a fairly high shear strength when it is compressed between the housing and the cable, in order to oppose the relative longitudinal movements thereof.

The housing serves as support for the wedging structure and connecting piece with the element to be fixed to the cable. It is preferably a one-piece piece that completely surrounds a section of the cable, but it is not mandatory. Such a one-piece piece is for example cylindrical with a circular or polygonal base. This housing can be made of metal or any other sufficiently rigid material.

Longitudinal compression is transmitted to the wedging structure by means of plates or rings or other parts bearing on the end surfaces of the wedging structure. The compression may be applied at one end, the other being in abutment against an abutment integral with the housing, or at both ends of the wedging structure, on all or only part of the accessible surface.

The force transmission means may comprise one or more members extending parallel to the cable, tensioned by clamping means to exert the longitudinal compressive force at the ends of the wedging structure. These tension members (bolts, preload strands, or any other suitable member) may pass through or around the wedging structure, through or outside the housing. The force transmission means may further comprise a nut screwed into a thread integral with the housing and applied against one end of the jamming structure.

The force transmission means may also be arranged to transform a longitudinal component of the load exerted on the cable by the construction element into a longitudinal compression of the deformable structure.

Other aspects of the invention relate to a method as recited in claim 17 or 18, using a device of the type previously indicated for attaching a construction element to a structural cable or, symmetrically, a structural cable to a construction element, and to a suspension bridge as set forth in claim 19.

• la figure 1 est un schéma de principe, en coupe longitudinale, d'un dispositif de fixation selon la présente invention ;
• les figures 2 à 6 sont des schémas en coupe transversale de différents modes de réalisation du dispositif de la figure 1 ;
• la figure 7 est un schéma en coupe longitudinale, suivant le plan VII-VII indiqué sur la figure 8, d'un autre exemple de dispositif de fixation selon l'invention ;
• la figure 8 est un schéma en coupe transversale de ce dispositif, suivant le plan VIII-VIII indiqué sur la figure 7 ;
• les figures 9 à 12 sont des schémas en coupe longitudinale d'autres exemples de dispositifs de fixation ;
• la figure 13 est un schéma en élévation d'une autre variante de réalisation ;
• la figure 14 est une vue en coupe longitudinale d'un dispositif de fixation non revendiqué ; et
• la figure 15 est un schéma d'un pont suspendu selon l'invention.

Other features and advantages of the present invention will become apparent in the following description of non-exemplary embodiments. with reference to the accompanying drawings, in which:

• the figure 1 is a schematic diagram, in longitudinal section, of a fastening device according to the present invention;
• the Figures 2 to 6 are cross-sectional diagrams of different embodiments of the device of the figure 1 ;
• the figure 7 is a diagram in longitudinal section, according to the plane VII-VII indicated on the figure 8 another example of a fixing device according to the invention;
• the figure 8 is a cross-sectional diagram of this device, according to the plan VIII-VIII indicated on the figure 7 ;
• the Figures 9 to 12 are diagrams in longitudinal section of other examples of fixing devices;
• the figure 13 is an elevation diagram of another alternative embodiment;
• the figure 14 is a longitudinal sectional view of an unclaimed fastener; and
• the figure 15 is a diagram of a suspension bridge according to the invention.

The Figures 1 and 2 show a fastening device installed around a cable 1, or group of cables. The element to be fixed is attached, by appropriate means, not shown, to a cylindrical housing 2.

A deformable wedging structure 3 having, in the example shown, the shape of an elastomeric sleeve, is placed around the cable 1 inside the cylindrical housing 2. Two bearing pieces 4, which can be shaped like rings, are respectively applied to both ends of the deformable structure 3, penetrating inside the cylindrical housing 2. A longitudinal compressive force F is exerted on the deformable structure 3 by means of the two support pieces 4. In the example shown, the force F is applied to each of the two parts 4 at both ends of the housing 2.

The deformable structure 3 is housed between the cable and the housing 2 with a certain radial clearance. When it is stressed in compression by the force F, it expands radially so as to be pressed inwards against the cable 1 and outwards against the cylindrical housing 2. It thus provides a friction between the cable 1 and the housing 2 which is attached to the element to be fixed. If the axial compression force F is sufficient, and if the structure 3 has an appropriate shear strength, this friction makes it possible to realize the desired fixation, preventing relative longitudinal movements between the cable 1 and the housing 2.

In the example of the figure 2 , the cable 1 is constituted by a set of juxtaposed strands 6. Each strand 6 may itself be composed of several elementary son. The deformable structure 3 has a shape complementary to the volume located between the periphery of the cable and the inner face of the housing 2. This shape can be obtained by molding the deformable structure 3, or else by deformation of an elastomer sleeve of original cylindrical shape .

In the variant of the figure 3 the strands 6 constituting the cable 1 are not juxtaposed, but spaced apart from each other. The elastomeric material of the deformable structure 3 is also in the gaps between the strands 6.

In the variant of the figure 4 , the cable 1 is constituted by a solid wire, of cylindrical section. The deformable structure 3 can then simply have the shape of a cylindrical sleeve.

In the example of the figure 5 , the cable 1 is constituted by a strand composed of seven twisted metal wires 7, protected by a plastic sheath 8, with an adherent material 9, for example an elastomer, between the wires 7 and the sheath 8. Such a strand is described in the application for European patent 0 855 471 . The cylindrical deformable sleeve 3 then bears against the sheath 8 of the strand. The friction of this sleeve 3 on the housing 2 and the sheath 8 provides the desired attachment, together with the adhesion of the material 9 to the wires 7 and the sheath 8.

In the examples of Figures 2 to 5 , the housing 2 is a one-piece piece of generally cylindrical shape. The base of this cylindrical shape is circular in the examples shown, but it will be noted that it could also be different, in particular polygonal. The fact that the housing 2 is a single piece allows it to be of relatively lightweight construction for a fastener resistant to a given load, especially lighter than if it were formed by assembling several shells, in the manner of conventional collars. In some configurations, the housing could however be an assembly of several parts.

The variant embodiment of the figure 6 shows that the housing 2a which is attached to the element to be attached may surround the cable 1 only partially. In the example shown, the cable 1 is surrounded by about 240 °, which allows the establishment of the housing 2a without it being necessary to put it on previously on the cable 1, which can facilitate mounting in some cases. Inwardly directed flanges 2b are located at the ends of the housing perimeter to maintain the deformable structure between the cable and the housing. The figure 6 also shows that the deformable structure 3 may consist of several elements 3a, 3b arranged around the cable 1.

The Figures 7 and 8 show a possible embodiment of the longitudinal compression transmission means in the case of a cable having a structure of the type shown in FIG. figure 3 . In this example, the deformable structure 3 consists of a block of elastomeric material traversed by seven cylindrical channels 11 of diameter slightly greater than the diameter of the seven strands 6 constituting the cable, and three other cylindrical channels 12 distributed symmetrically on the section of the housing and intended to receive three threaded rods 13 of slightly smaller diameter. The threaded rods 13 pass through corresponding holes provided in the bearing parts 4. The rods 13 protrude at both ends of the casing 1, where they receive nuts 14. The tightening of these nuts puts the rods 13 in tension so as to exert longitudinal compression on the deformable structure 3. Under the effect of this compression, the deformable structure 3 bears on the inside of the housing 2 and clamps the strands 6.

Alternatively, the threaded rods 13 could pass outside the deformable structure 3, through the wall of the housing 2 or outside thereof. These rods could still be replaced by other members working in tension, such as prestressing strands anchored at their ends by conical keys.

In the advantageous realization of the figure 9 , the deformable wedging structure comprises several (three in the example shown) sections of deformable material 3c, 3d, 3e arranged successively along the cable 1. The end sections 3c, 3e are stressed in compression by the parts of support 4, while rigid inserts 15 are placed between the adjacent sections. These inserts 15 extend radially between the cable and the housing. It can especially be shaped rings. Their role is to limit the creep of the deformable material of the wedging structure from the side of the cable 1 where the transverse loads are applied to the opposite side. They provide support for the cable 1 if such creep occurs, and once this support is achieved, creep ceases since the deformable material is almost no longer solicited transversely. Advantageously, the inserts 15 and the support pieces 4 have radial clearances with respect to the cable 1, adjusted so that it follows a constant or substantially constant radius of curvature when it bears on these inserts, to minimize undesirable curvatures.

In the embodiment of the figure 10 , the longitudinal compression force is applied to one side only of the housing 16. At the other end of the housing, the deformable structure 3 is retained by a portion secured to the housing 16, such as for example a flange 17 directed towards the inside. On the side where the clamping is applied, the bearing piece 18, in the form of a ring bearing on the deformable structure 3, has a flange 19 directed outwards and provided with holes receiving bolts 21 fixed to the housing. The tightening of nuts 22 on the bolts 21 then makes it possible to compress the structure 3 between the flange 17 and the support rings 18.

The fixing device shown on the figure 10 comprises a regulating member penetrating inside the housing 16 transversely to the direction of the cable. This member consists of a screw 23 that can be penetrated more or less deeply into the housing 16 to vary the available volume for the deformable structure 3, which allows to vary the clamping procured.

In the example of the figure 10 , the cable 1 consists, as indicated with reference to the figure 5 , in one or more strands protected by an individual sheath 8 made of plastic, for example high density polyethylene (HDPE), and the deformable structure 3 is made of elastomer, for example neoprene. An intermediate rigid layer 24 is disposed between the deformable structure 3 and the sheath 8 of the cable, to take account of the poor coefficient of friction between the HDPE and the neoprene. This layer 24 may in particular be HDPE, the coefficient of friction HDPE / HDPE is better. On its outer face, that is to say in the direction of the deformable structure 3, the intermediate layer 24 has transverse reliefs to the direction of the cable, such as ridges 25, to increase the friction.

The figure 11 shows a variant of the realization according to the figure 10 , in which the intermediate rigid layer 26 ends, on the side of the inner rim 17 of the housing 16, by an outer rim 26a. The flanges 17 and 26a are in axial abutment on one another, and the deformable structure 3 is compressed longitudinally between the flange 26a and the support ring 18 which urges towards the said flanges the end of the wedging structure opposed to that which is in support against the edge 26a. This ensures the radial clamping between the housing 3 and the intermediate layer 26, the latter transmitting the clamping to the cable 1. In this variant, the only interface working in friction is that between the layer 26 and the cable 1, which allows eliminate any slip problem that may occur on the surface of the deformable material.

The Figures 12 and 13 show embodiments in which the longitudinal compressive force applied to the deformable structure results from a transformation of the longitudinal component of the load C exerted on the cable by the element to be fixed. In the two examples shown, the cable 1 is in an inclined position, and the load C is directed vertically.

In the example of the figure 12 , an annular stop 27 is fixed on the cable 1, exerting a moderate tightening thereon. The lower end of the deformable structure 3 is supported on this stop 27, and its upper end on an inner rim 28 secured to the housing 29. The load C transmitted to the housing 29 by the element to be fixed has a longitudinal component C _L directed from the upper end to the lower end of the deformable structure. This component C _L urges the rim 28 towards the deformable structure 3, which is compressed between the stop 27 and the flange 28. It should be noted that the sliding resistance offered by the device is greater than that provided for the only stop 27 attached to the cable.

In the case of figure 13 , the element to be fixed 31 is attached to a lever 32 articulated at its opposite end on a support 33 secured to the housing 34, the hinge axis A being horizontal and perpendicular to the cable 1. An intermediate zone of the lever 32 is applied against a support piece 35 penetrating the housing 34 where it exerts the longitudinal compressive force at one end of the deformable structure, the opposite end of which abuts against a rim 36 integral with the housing 34, as shown by the tearing away of the case in the figure. This arrangement transmits the longitudinal component C _L of the load to the deformable structure 3, with an amplification depending on the dimensions of the lever 32.

In the fixing device shown in the figure 14 , which is not directly concerned by the present invention, the housing 50, of generally cylindrical shape, is traversed by an axial frustoconical orifice 51. In the case of a hanger hanging collar, a rib 52 is welded to the outside of the cylindrical housing 50 to receive a clevis attached to the end upper line.

The cylindrical housing 50 further comprises two internal threads 53, 54 on either side of the frustoconical orifice 51. The thread 53 is formed at the periphery of a cylindrical recess 55 formed above the frustoconical orifice 51 (to the left of the figure 13 ). This orifice 55 receives the lower end of a sheath member 56 provided with a radial shoulder 57. An externally threaded nut 58 bears against the shoulder 57 and cooperates with the thread 53 to connect the sheath member 56. to the case 50.

The thread 54 is formed at the periphery of another cylindrical recess 60 formed below the frustoconical orifice 51. This thread 54 receives a complementary external thread 61 formed at one upper end of another sleeve section 62 in order to connect this section of sheath 62 to the housing 50.

The sheath sections 56, 62 extend between two consecutive collars on the carrying cable. The sheath sections 62 connected to the lower sides of the housings 50 have a diameter slightly greater than that of the sheath sections 56 connected to the upper sides of the housings. These two sections of sheath 56, 62 overlap over a certain length in the interval separating two collars. This telescopic overlap makes it possible to shorten the sheath between the collars to facilitate assembly, and allows differential expansions between the materials.

This provides a protective sheath of the carrier cable which connects continuously at the collars, which provides reliable protection and good overall aesthetics. Another advantage is obtained when it is requested that it is possible to blow dry air into the sheath of a suspension bridge carrying cable in order to eliminate moisture: the realization of the figure 14 makes it possible to easily achieve the required sealing at the hangings of lines while allowing air to circulate, while this poses serious difficulties with the previous collars formed by bolting of several shells.

The frustoconical orifice 51 of the casing 50 receives a complementary frustoconical jaw 64 which jams between the cable and the casing. As is usual, the jaw 64 may be constituted by a plurality of distinct angular sectors, for example three in number. Toward the lower side of the casing 50, which corresponds to the end of larger diameter of the orifice and the frustoconical jaws, the jaw 64 is urged by a nut 65 provided with a thread outside cooperating with the thread 54.

Before hanging the suspension on the plate 52, the nut 65 is screwed into the recess 60 in order to drive the jaw 64 towards the upper end of smaller diameter of the frustoconical orifice 51. The jaw 64 is thus found compressed longitudinally between its frustoconical interface with the housing 50 and its rear end urged by the nut 65.

At the moment when this tightening is exerted, the jaw 64 undergoes a longitudinal compression, controlled by the tightening of the nut 65, which results in a transverse tightening of the cable 1. By exerting this tightening, the housing can be secured beforehand on the cable (or the cable in the case), then set up the assembly while maintaining the positioning of the components. When the load is then transmitted by the hooking of the lines, the longitudinal compression force increases because of the load transmitted by the housing 50 (to the right on the figure 14 ), and the positioning is not changed.

In addition, the fastening device according to the figure 14 is always in a safe condition, due to the self-jamming operation including in cases where a slight upward movement of the hanger may occur. The assembly is also self-jamming in case of accidental overload on the hanger.

The force transmission nut 65 is tightened by means of a suitable tool, such as a hook wrench, to a predefined torque in order to ensure sufficient clamping between the cable 1 and the housing 50.

In the case of a multi-strand cable, the clamping efficiency can be increased by filling voids between the strands by means of curvilinear plastic inserts (see EP-A-0 789 110 ). To increase the coefficient of friction between the strands, and / or between the strands and the jaw, it is also possible to place a fiberglass fabric around the strands.

To limit the creep of the frustoconical jaw 64, it can be made of plastic, for example HDPE or polyamide, and the volume it occupies is confined.

Once the controlled tightening has been exerted with the nut 65, care is taken to avoid additional fluidisation of the material of the jaw 64. For this purpose, the jaw is confined as far as possible in its frustoconical housing. In particular, it is possible to use a shim 66, represented at the upper part of the figure 14 , which is applied against the end of the smaller section of the bit 64 after tightening, to seal this end and prevent excessive creep of the material of the jaw. On the opposite side, the nut 65 has a configuration to also avoid the creep of the material of the jaw.

• on découpe les tronçons de gaine 56, 62, et on soude à leurs extrémités les pièces de raccordement comportant les rebords 57 et les filetages 61 ;
• on découpe à la longueur exacte les torons constitutifs du câble 1 ;
• on marque précisément sur les torons la position de chaque boîtier 50 pour l'accrochage des suspentes 41 et/ou la pose au sommet des pylônes 40 ;
• on enfile autour du câble les tronçons de gaine 56, 62, les écrous 58, 65, les mors 64, les boîtiers 50 et les cales optionnelles 66, dans l'ordre approprié depuis une extrémité du câble ou les deux ;
• on amène chaque boîtier 50 à l'emplacement spécifié sur le câble et après avoir engagé le mors 64 dans son orifice 51, on l'enfonce en appliquant le serrage requis au moyen de l'écrou 65 ;
• après avoir serré l'écrou 65, on engage l'extrémité de l'élément de gaine 56 et la cale optionnelle 66 dans l'évidement 55, et on raccorde cet élément de gaine 56 au boîtier 50 au moyen de l'écrou 58; sur le côté opposé du boîtier 50, on engage également l'élément de gaine 62 en vissant son extrémité filetée 61 dans l'évidement 60 ;
• après avoir mis en place tous les boîtiers de cette manière, on installe le câble en position sur les pylônes, et on procède aux ancrages des extrémités des torons puis à l'accrochage des suspentes.

To assemble the supporting structure of a suspension bridge made using fastening devices according to the figure 14 we proceed as follows:

• the sheath sections 56, 62 are cut, and the connecting pieces comprising the flanges 57 and the threads 61 are welded at their ends;
• the constituent strands of the cable 1 are cut to the exact length;
• the strands are precisely marked on the position of each casing 50 for hooking up the lines 41 and / or laying on top of the pylons 40;
• the sleeve sections 56, 62, the nuts 58, 65, the jaws 64, the housings 50 and the optional shims 66 are threaded around the cable in the appropriate order from one end of the cable or both;
• each housing 50 is brought to the specified location on the cable and after engaging the jaw 64 in its hole 51, it is pressed by applying the required clamping by means of the nut 65;
• after tightening the nut 65, engaging the end of the sheath member 56 and the optional shim 66 in the recess 55, and connecting this sheath member 56 to the housing 50 by means of the nut 58; on the opposite side of the housing 50, the sheath member 62 is also engaged by screwing its threaded end 61 into the recess 60;
• after setting up all the housings in this way, the cable is installed in position on the pylons, and the ends of the strands are anchored and then the hanging lines.

Thanks to the fixing device used, this way of proceeding allows a precise and reliable assembly of the supporting structure.

It should be noted that the same procedure provides similar advantages of reliability and accuracy when using a device according to one of the Figures 1 to 11 , in which a deformable wedging structure is used in place of a frustoconical jaw.

A relatively aesthetic assembly is also achieved thanks to the continuity of connection of the sheath sections 56, 62. However, it will be noted that this protective sheath 56, 62 is optional. In another embodiment, particularly suitable in the case of total prefabrication, the sections of sheath extend in one piece from one collar to another, which improves the seal.

The figure 15 schematically illustrates a suspension bridge having one or more carrying cables 1 equipped with fastening devices according to the invention. The carrying cable 1 is anchored at both ends of the bridge, and it passes on the towers 40. The lines 41 are hung on the carrier cable to support the apron 42 of the bridge. The lines 41 are attached to the carrier cable at their upper ends which are attached to housings 43 forming part of fasteners of the type previously described. These devices prevent the vertical lines 41 from sliding along the cable under the effect of the component parallel to the cable of the load exerted vertically by the deck 42. In the case of a suspension bridge having no suspension, the element of construction connected to the housing 43 may be directly a secured portion of the deck.

The carrier cable 1 is deflected at the top of the pylons 40, where the tensile force can be asymmetrical. It may therefore be necessary to block the cable to prevent it from sliding relative to the pylons. For this, we install at the top of the pylons 40 boxes 44 surrounding the cable 1 to block it in relation to the pylons as previously described.

Claims (20)

1. A device for fixing together a construction element (40, 41) and a structural cable (1), comprising a rigid housing (2 ; 16) connected to the construction element and surrounding the cable, a wedging structure (3) arranged between the cable and the housing, and load transmitting means (4,13,14 ; 17,18,21,22) arranged to exert a longitudinal compressive force (F), parallel to the cable, on the wedging structure, the wedging structure being pressed against the cable and the housing under the action of the longitudinal compressive force, so as to offer resistance to movement of the housing and of the construction element parallel to the cable, characterized in that the wedging structure comprises at least one elastomeric deformable material.
2. A device according to claim 1, wherein the wedging structure (3) comprises an elastic material, a granular material and/or a fibrous material.
3. A device according to claim 1 or 2, wherein the wedging structure comprises several portions made of deformable material (3c, 3d, 3e) arranged in the longitudinal direction and separated by inserts (15) running radially between the cable (1) and the housing (2).
4. A device according to claim 3, wherein the inserts (15) exhibit radial clearance with respect to the cable (1), the clearance being tailored so that the cable follows a substantially constant radius of curvature when resting on said inserts.
5. A device according to any one of claims 1 to 4, comprising at least one adjusting member (23) penetrating the housing (16) transversely to the direction of the cable, so as adjustably to restrict the volume available for the deformable material of the wedging structure (3).
6. A device according to any one of claims 1 to 5, wherein the load transmitting means comprise at least one member (13 ; 21) running parallel to the cable (1), tensioned by clamping means (14 ; 22) so as to exert the longitudinal compressive force on ends of the wedging structure (3).
7. A device according to claim 6, wherein said member (13) extends through the wedging structure (3).
8. A device according to claim 6, wherein said member extends around the wedging structure (3) through or around the outside of the housing (2).
9. A device according to any one of claims 1 to 5, wherein the load transmitting means comprise at least one nut (65) screwed into a screw thread (54) integral with the housing (50) and applied against an end of the wedging structure (64).
10. A device according to any one of claims 1 to 5, wherein the load transmitting means (27,28 ; 32,35,36) are arranged to convert a longitudinal component (C_L) of the load exerted on the cable (1) by the construction element into a longitudinal compression of the wedging structure (3).
11. A device according to claim 10, wherein the load transmitting means comprise a stop (27) fixed to the cable, against which a first end of the wedging structure (3) bears, and a part (28) integral with the housing (29) bearing against a second end of the wedging structure opposite the first end, the longitudinal component (C_L) of the load exerted on the cable by the construction element being directed from the second end toward the first end.
12. A device according to claim 10, wherein the housing (34) has an internal rim (35) against which a first end of the wedging structure (3) bears, and wherein the load transmitting means comprise a lever (32) articulated to a part (33) integral with the housing, by means of which the construction element (31) is connected to the housing, and a transmission member (35) bearing against a second end of the wedging structure opposite the first end and to which a portion of the lever applies the longitudinal compressive force in response to the load exerted by the construction element.
13. A device according to any one of claims 1 to 12, wherein a fiberglass fabric is inserted between the cable (1) and the wedging structure and/or between the constituent strands of the cable.
14. A device according to any one of claims 1 to 13, wherein the cable (1) is protected by at least one plastic sheath (8), and wherein a rigid intermediate layer (24, 26) is arranged between the wedging structure (3) and the cable sheath.
15. A device according to claim 14, wherein the wedging structure (3) is deformable and wherein the intermediate layer (24) exhibits, toward the deformable wedging structure (3), reliefs (25) transversal to the direction of the cable (1).
16. A device according to claim 14, wherein the rigid intermediate layer (26) has an external radial rim (26a) against which a first end of the wedging structure (3) is applied, wherein said rim of the rigid intermediate layer is axially in abutment against an internal radial rim (17) of the housing (16), and wherein the load transmitting means comprise means (18,19,21,22) for compressing the wedging structure by urging a second end of the wedging structure opposite the first end toward said rims.
17. A method for fixing a construction element (41) to a structural cable (1), comprising: placing around the cable a rigid housing (2 ; 16) for transmitting a load of the construction element to the cable; placing a wedging structure(3) comprising at least one elastomeric deformable material between the cable and the housing; and compressing the wedging structure longitudinally, parallel to the cable, before the load of the construction element is applied, so that the wedging structure is pressed against the cable and the housing to offer resistance to movement of the housing and of the construction element parallel to the cable.
18. A method for fixing a structural cable (1) to a construction element (40), comprising: placing around the cable a rigid housing (2 ; 16) for transmitting a load of the construction element to the cable; placing a wedging structure (3) comprising at least one elastomeric deformable material between the cable and the housing; and compressing the wedging structure longitudinally, parallel to the cable, before the load of the construction element is applied, so that the wedging structure is pressed against the cable and the housing to offer resistance to movement of the cable with respect to the housing and to the construction element.
19. A suspension bridge comprising at least one suspension cable (1) and construction elements for supporting a deck of the bridge, at least some of the construction elements (40,41) being fixed with respect to the suspension cable by means of devices according to any one of claims 1 to 16.
20. A suspension bridge according to claim 19, wherein the construction elements fixed with respect to the suspension cable (1) by means of said devices comprise tops of towers (40) of the bridge where the suspension cable is deflected, and/or hangers (41) connected to the deck of the bridge, and/or sections of the deck of the bridge.

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