EP3658711A1

EP3658711A1 - Improved assembly comprising a structural cable and a saddle

Info

Publication number: EP3658711A1
Application number: EP18752597.7A
Authority: EP
Inventors: Nicolas FABRY; Nicolas Vincent; Francis DUMESNIL
Original assignee: Soletanche Freyssinet SA
Current assignee: Soletanche Freyssinet SA
Priority date: 2017-07-28
Filing date: 2018-07-20
Publication date: 2020-06-03
Also published as: WO2019020911A1; US20200199831A1; CA3071452A1; FR3069555A1

Abstract

The assembly comprises a structural cable comprising tensioned strands (12) and a saddle diverting the structural cable between the two ends of same. The saddle comprises a body (18), conduits (24) formed in the body and each receiving one of the strands of the cable, and two anchoring devices (20) that anchor the strands, defining a first portion of the structural cable received in the saddle where the strands are subjected to a preload tension that is constant over time, and at least one second portion of the structural cable where the strands are subjected to tensions that are variable over time. An anchoring device (20) comprises an anchoring plate (28) comprising anchoring openings (36) that each receive one of the strands, and jaws (30), each received in a respective anchoring opening of the anchoring plate in order to immobilise one of the strands of the structural cable there. The anchoring plate (28) has a back surface bearing against the body (18).

Description

Improved assembly including structural cable and saddle

The present invention relates to devices used to deflect structural cables, including guy wires.

Such cables often include a bundle of individual strands stretched and anchored at their ends.

The design of a construction structure, including a bridge, may cause the cable to be deflected in one or more areas of its route.

For example, it is known to use pylons crossed by stays having a path in the general shape of inverted V. The stays are then deflected into the pylons using a saddle.

This saddle aims in particular to deflect the strands of the cable without altering the mechanical strength, and sometimes to mobilize sufficient friction between the strands and saddle ducts which each receive a strand for optimal recovery by the pylon receiving saddle efforts differentials applied to the cable on either side of the pylon.

A possible general saddle configuration is based on the anchoring in the saddle of the cable so as to define, within the saddle, a portion of cable subjected to a predetermined tension and substantially constant in time. This configuration results in the presence in the saddle of anchoring devices adapted for this purpose. CN 20250087 U illustrates such a configuration.

One of the difficulties encountered relates to the difficulty of designing such anchoring devices which are optimized from the mechanical point of view and allow optimum protection of the strands against corrosion and mechanical actions.

An object of the present invention is to improve the mechanical behavior of the cable and associated equipment in a deviating saddle, while ensuring optimum protection of the reinforcements that constitute it.

For this purpose, the invention relates to an assembly comprising:

a structural cable having a plurality of tensioned strands anchored at two opposite ends of the structural cable between which they extend continuously; and

a saddle configured to deflect the structural cable between its two ends.

The saddle includes: a body ;

a plurality of conduits formed in the body and each receiving and guiding one of the strands; and

two anchoring devices configured to anchor the strands so as to define a first portion of the structural cable received in the saddle, wherein the strands are subjected to a substantially constant prestressing tension over time, and at least a second portion of the structure cable where the strands are subjected to variable voltages over time.

At least one of the two anchoring devices comprises:

an anchor plate having anchor holes each receiving one of the strands, the anchor plate having a rear surface bearing against the body; and

jaws each received in a respective anchor hole of the anchor plate to block one of the strands of the structural cable.

Typically, the body is made of a material molded inside a tubular casing of the saddle.

In one embodiment, each strand of the structural cable is coated with an individual sheath removed at the anchoring device. The anchoring orifices may then be of frustoconical shape through the anchor plate, the frustoconical shape having a minimum diameter strictly greater than the diameter of the strand coated with the individual sheath.

At least one of the anchoring holes may receive a fur surrounding the jaw to define in the anchor port a passage of smaller section than the anchor hole, through which a strand passes through the anchor plate.

Alternatively, for at least one anchoring orifice, the jaw is in direct contact with the frustoconical wall of the anchoring orifice to anchor the strand in the anchor plate.

At the anchoring device, the individual sheath of each strand can be removed on a portion of length less than three times the length of the jaw.

In one embodiment, the anchor plate has a thickness of between 1 and 1.5 times the length of the jaw.

The seat may be equipped with at least one guide member comprising a plurality of guide channels each receiving a strand and configured to guide the angular movements of the strands in at least a second portion of the cable. The saddle may further comprise a sealing system including an axially compressed seal for sealing around the strands, the anchor plate of one of the anchoring devices being located between the sealing system and the saddle body. .

When the seat comprises at least one guide member provided with a plurality of guide channels each receiving a strand and configured to guide the angular movements of the strands in at least a second portion of the cable, the sealing system can advantageously be placed between the guide member and the anchor plate of said anchoring device.

In one embodiment, an O-ring is placed in each conduit formed in the body to receive a strand of the structural cable, and a protective material is injected into a volume sealed by the axially compressed seal and the O-rings and containing the pressure plate. anchorage and bit. If each strand of the structural cable is coated with an individual sheath, this sheath can be removed in a region between the O-ring and the axially compressed gasket.

In one embodiment, the anchor plate has its rear surface bearing on the body, a front surface and a peripheral surface freely received in a housing coaxial with the structural cable at the anchoring device.

Another aspect of the present invention relates to a method of deflecting a structural cable having a plurality of tensioned strands. The method comprises:

providing a seat body in a region between two ends of the structural cable, the body being formed with a conduit for each strand of the structural cable; engaging each strand in an anchor hole of a first anchor plate, in one of the conduits formed in the body and then in an anchor hole of a second anchor plate;

tensioning the strands to a predefined prestressing tension in a first portion of the structural cable between the first and second anchor plates and locking the strands in each of the first and second anchor plates, while the first and second anchor plates anchoring each have a rear surface bearing against the saddle body; and

anchoring the structural cable at both ends so that the strands are subjected to varying voltages over time in two second portions of the structural cable each located between one end of the structural cable and one of the first and second anchor. In one embodiment of the method, each strand is successively threaded into a guide channel of a guide member of a first anchoring device, into a passage formed in a sealing system of the first anchoring device. in the first anchor plate belonging to the first anchor, in one of the conduits formed in the body, in the second anchor plate belonging to a second anchor, in a passage formed in a system sealing of the second anchoring device and in a guide channel of a guide member of the second anchoring device.

When each strand of the structural cable is coated with an individual sheath, it is possible, after engagement of a strand in an anchoring orifice, to remove the individual sheath of the strand at said anchoring orifice to insert a jaw of blockage of the strand.

In one embodiment of the method, after tensioning the strands in the first portion at the prestressing and locking tension in the first and second anchor plates, the tension is released and the strands are tensioned in each second portion to a value lower than the prestressing tension before anchoring the structural cable at both ends.

Tensioning and locking the strands in one of the first and second anchor plates, located at the rear of a housing formed in a tubular casing receiving the seat body, may comprise:

applying a tension over the entire length of at least one strand at at least one end of the structural cable;

arranging an overlock device comprising at least one jack on a front side of the housing; and

actuating the jack for, around said strand, push a jaw into an anchor hole of said anchor plate.

The invention will be better understood on reading the detailed description which follows, given solely by way of example and with reference to the appended figures, in which: FIG. 1 illustrates a cable-stayed bridge comprising an assembly according to the invention; Figure 2 shows the deviation of a stay at a bridge pylon;

FIG. 3 illustrates an anchoring device that can be used according to the invention; and

Figure 4 is a diagram of an apparatus for use in a method according to the invention. Figure 1 illustrates a construction structure 2 comprising a plurality of structural cables 4. In the following non-limiting description, the structural cables 4 are guy wires. The construction work 2 is for example a cable-stayed bridge.

In this configuration, the structure 2 further comprises an apron 6 and a pylon 8 in which the stays 4 are received and deflected. The stays 4 are for example anchored at their ends in the deck 6, and are thus configured to suspend the deck.

The pylon 8 comprises, for at least one stay 4, a saddle 10, in which the corresponding stay 4 is received and deflected. Each saddle 10 can receive a single stay 4.

Referring to Figure 2, which illustrates a saddle 10 and the stay 4 received therein, the saddle 10 and the stay 4 there deflected form an assembly within the meaning of the invention.

The stay 4 comprises a first portion A received in the saddle 10 where the tension is constant over time. This voltage corresponds to a prestressing tension for this portion A, which results from the tensioning of constituent strands of the stay at a prestressing tension. In addition, the stay 4 comprises at least a second portion B extending away from the first portion A, where the voltage is variable over time and is lower than the prestressing voltage of the portion A. The portion A and the portion B are successive, the portion B being in the continuity of the portion A.

For example, the stay 4 has two second portions B each extending from one end of the first portion A away from the saddle. These portions B extend from the corresponding end of the portion A to one of the ends 4E of the stay 4.

Thus, in the typical configuration of the invention, the stay includes between its ends, three successive portions B, A, B.

The portions B are substantially rectilinear, but may have a chain of arrow less than or equal to 0.5% of the length of the stay 4. The portion A is preferably curved.

The stay 4 is anchored and tensioned at its opposite ends 4E. The anchoring of these ends is for example implemented by anchors of the active type also adapted for the tensioning of the stay.

The stay 4 comprises a sheath 11 and at least one strand, or armature, 12 stretched and arranged in the sheath 11. The sheath 11 is for example made of HDPE, for high density polyethylene. It comprises two portions 111, 11 ₂ respectively covering at least a portion of one of the second portions B, the sheath 11 being absent from the portion A.

Advantageously, the sheath 11 extends cumulatively over the majority of the portions B, for example a portion of length greater than 80% of the cumulative length of these portions.

With reference to FIG. 3, each sheath portion 111, 11 ₂ associated with a portion B is attached to the saddle 10 and / or to the pylon 8.

Advantageously, each sheath portion comprises a connecting sleeve 11C forming an end of this portion facing the saddle 10, and intended to be fixed to the saddle 10 (and / or the pylon), as described below.

Each sheath portion 111, 11 ₂ comprises, near its end adjacent to the saddle, a flexure sleeve 11L adapted to accommodate bending of the sheath portion in this region.

In the context of the invention, each strand 12 extends from one end 4E of the stay to the other end 4E, without interruption. It is anchored in the end anchorages of the stay 12.

As a result, the stay 4 has no coupler between disjoint segments of a strand.

Each strand 12 has a metal strand 14 forming the main structural part of the strand. In one embodiment, each strand 12 also includes an individual sheath 16, which surrounds the strand 14 over at least a portion of its length. This sheath is for example plastic, such as HDPE.

This sheath extends over a portion of the portion A within the saddle 10. In addition, the sheath 16 of a strand 12 extends over at least one region of the portions B of the strut, and preferably on the entirety portions B.

The strand 12 has for example an outer diameter of between 15 and 22 mm on its sheathed portion, and is for example 19.5 mm. In addition, the strand 14, that is to say the strand 12 on a portion free of sheath 16, has an outer diameter of between 12 and 17 mm, and is for example 15.7 mm.

Each strand 12 optionally comprises an anti-corrosion protection material coating the strand 14 and contained in the sheath 16. This material is advantageously lubricant. For example, the material is or includes wax, grease, or a polymer resin.

With reference to Figures 2 and 3, the seat 10 is received in the pylon 8 and extends inside thereof at least in part. The saddle 10 joins an outer face of the pylon to an opposite face. These two faces are here transverse faces of the pylon. However, in other configurations, the ends of the saddle 10 are offset from the pylons and project out of the pylon.

The saddle 10 comprises a body 18, a tubular casing 22 and two anchoring devices 20 for anchoring the strands 12 of the stay 4 in the saddle 10 and the definition of the portions A and B of the stay.

The envelope 22 forms the framework of the saddle 10. It is arranged in the saddle 10 and delimits internally, that is to say in its interior volume, the saddle body 18

This envelope 22 is for example of polygonal section, such as rectangular. Alternatively, this section is circular.

The envelope 22 advantageously comprises diaphragms (not shown) orthogonal to the direction in which the envelope 22 extends. This direction corresponds to the mean line of the envelope 22, which follows the deflected path of the stay 4 received in the 10. The diaphragms are configured to strengthen the saddle. They define successive body regions 18 within the envelope 22. These diaphragms are pierced at least for the passage of the strands 12 of the stay. They materialize the position of the ducts formed through the body 18 and delimit the section locally.

The seat body 18 has a plurality of individual ducts 24. Each duct 24 passes through the body and is provided for receiving and guiding a single strand 12 of the stay 4 associated with the saddle 10 from one end to the other 18. Each strand 12 bears on the walls of the conduit 24 corresponding on at least a part of its length, which guides the strand along the curve of the saddle. Advantageously, the walls of the ducts 24 are smooth, with a geometry minimizing the friction between the sheath 16 of the strands and the walls of the ducts 24. Alternatively, these walls are configured to allow high friction between the strands and the saddle 10.

The directions, or average lines, respective ducts 24 are preferably parallel to each other. These directions present a trajectory curve, comprising for example a central segment in the form of a circular arc, thus giving the portion A of the stay cable this trajectory.

The body 18 is preferably made of molded material such as concrete. The concrete in question has a suitable mechanical strength to support the support and guidance of each strand 12 in an individual conduit 24 without damaging its sheath 16. In order to limit the metal reinforcement required for this resistance, the concrete used is advantageously type BFUHP (for Ultra-High Performance Fibrated Concrete).

Advantageously, the body 18 and the envelope 22 define, at at least one of the longitudinal ends of the body and the envelope, a housing 26 coaxial with the structure stay at one of the anchoring devices 20. Advantageously, this is the case for each of the longitudinal ends of the envelope 22. In other words, the seat 10 comprises, at each of its ends, a housing 26 for receiving one of the anchoring devices 20.

The anchoring devices 20 are configured to anchor the strands 12 of the stay 4 so that the portion of stay A located between these anchoring devices 20 is subjected to a so-called prestressing tension, substantially constant in time. Thus, this portion of stay is subjected to a tension made independent of the tension prevailing in the portions of stay B located beyond these anchoring devices, which is likely to vary, in particular under the effect of the passage of convoys on the bridge, under the effect of the wind, thermal expansion phenomena, etc.

Each anchoring device 20 is arranged in one of the housings 26 located at the longitudinal ends of the saddle 10, and is held there in place.

Each housing 26 occupies the entire volume delimited radially by the tubular envelope 22. In addition, each housing 26 is delimited longitudinally between the body 18 and the end of the saddle 10, which is advantageously at one of the pylon faces.

Still with reference to FIG. 3, each anchoring device 20 comprises an anchor plate 28 and for each strand 12, a jaw 30 intended to cooperate with both the associated strand 12 and the anchor plate 28 to anchor the strand 12. In addition, each anchoring device 20 comprises a retaining plate 32 adapted to hold the jaws in position in the anchoring plate 28.

The anchor plate 28 is configured to receive the jaws 30 of the different strands 12 for anchoring to the saddle 10. The anchor plate 28 has its rear surface applied against the end of the body 18 defining the housing 26.

The anchor plate 28 bears against the body 18. More specifically, when the anchoring plate 28 is flat, it bears against a flat surface of the body, advantageously formed by an end face of the body.

In a first configuration, the plate 28 bears directly against the molded and hardened material of the body 18.

Alternatively, in a second configuration, the plate 28 bears against the body via a flat wall 34 interposed between the body 18 and the anchoring plate 28. This wall 34, which corresponds to a diaphragm of end of the tubular casing 22 could serve as a formwork, with the casing 22, during the molding of the BFUHP or other material of the body 18. It is perforated for the passage of formwork elements used to form the ducts 24 through 18. The formwork elements forming the ducts 24 may be in the form of elastomeric tubes or cylinders. They are engaged in the holes present in the walls 34 of the two anchoring devices 20 on both sides of the saddle and in the intermediate diaphragms. Once the material of the body 18 has been poured and hardened, they are extracted by pulling on their ends protruding from the walls 34. During their extraction, they detach from the molded material due to the reduction of their section caused by the applied traction and their elasticity.

As the anchor plate 28 is placed in abutment against the body 18 (directly or through the wall 34), it is almost not bending stressed when the prestressing tension is applied to the strands in the portion A of the stay.

Advantageously, the support of the rear surface of the anchoring plate 28 against the body 18 is formed so that the region of the anchoring plate 28 in which the anchoring orifices 36 described below are inscribed is in bearing against the body 18 on substantially its entire rear surface. In other words, the net section of the anchor plate 28 is entirely in abutment against the body 18, that is to say in full contact with the body 18 or the wall 34. In particular, as in the configuration illustrated on 3, the entire rear surface of the plate 28 can bear against the body 18 or the wall 34.

The rear surface of the anchor plate 28 and the surface on which this rear surface bears (front surface of the body 18 or the wall 34) have a good flatness. In some embodiments, a plugging product is disposed between these two surfaces so as to form an interface seal providing a stable support. This product is for example a slurry or a resin.

The anchor plate 28 has an outer section whose shape advantageously corresponds to that of the inner section of the casing 22 at the housing 26, for example polygonal or circular. To further ensure good support of the rear surface of the anchor plate 28 on the body 18, it is desirable that its peripheral surface is freely received in its housing formed by the casing 22, for example by having a radial clearance as we see it in figure 3.

The anchor plate 28 is advantageously made from metal, for example steel. The steel in question is a grade offering sufficient mechanical strength with respect to bursting stresses induced in the anchoring plate 28 by the radial clamping exerted by the jaws 30 on the strands 12 for their anchoring.

The anchoring plate 28 comprises anchoring orifices 36 each intended for the passage of a strand 12 and the reception of the jaw 30 serving to anchor this strand to the plate 28.

Each anchoring orifice 36 extends perpendicularly to the bearing surface of the anchor plate 28, being aligned with one of the ducts 24 of the body 18.

Each anchoring orifice 36 is aligned with the local direction of the corresponding strand 12, possibly with a slight angle to the direction of the duct 24 at its outlet, as shown in FIG. 3, to allow detachment of the strand 12 from the inside face. duct near the anchor plate 28.

Each anchoring orifice 36 has a generally frustoconical shape and internally defines a frustoconical passage from the rear surface to the front surface of the anchor plate 28 for the passage of a strand 12. The smallest section of the orifice anchor 36 is turned towards the body 18.

The minimum diameter of the anchoring orifice 36 is strictly greater than the diameter of the strand 12 provided with the individual sheath 16. The individually wrapped strand 16 can thus be threaded into the anchoring orifice without coming into contact with the plate. anchor. For example, this minimum diameter is between 21 mm and 26 mm.

The anchoring orifices 36 have a maximum diameter of between 31 mm and 36 mm, for example. The anchoring orifices 36 may all be identical in shape and size.

Each anchor plate 28 defines one end of the portion A of the stay. Thus, in Figure 3, the portion of the stay located to the left of the plate 28 is part of the portion B, the right portion being part of the portion A.

Each jaw 30 anchors a strand 12 to the anchor plate 28 by conical wedging.

For example, each jaw 30 is composed of three wedges shaped truncated cone sectors, assembled around the strand 14 with a ring engaged in a circumferential groove provided near their widest end. These three keys are placed around the strand 14 after installation of the strand 12 in the saddle 10. To receive the strand 14, the jaw 30 formed by assembly of the three keys has an axial bore whose inner face may have streaks serving to increase the strand friction -mors.

Each jaw 30 has a length noted Lm. This length, corresponding to the size of the jaw along the axis of its frustoconical shape, is identical for all the jaws 30 of a given anchoring device, and advantageously between the various anchoring devices 20.

The anchor plate 28 has a thickness of between one and three times the length Lm of a jaw 30. Preferably, this thickness is between 1 and 1.5 times Lm.

In one embodiment of the invention, the anchoring device 20 comprises a fur, or jacket 38 in each anchoring orifice 36. This fur 38 is arranged between the jaw 30 and the frustoconical face of the anchoring orifice for reducing the dimensions of the passage of the anchor plate receiving the corresponding strand and defined internally in the anchoring orifice 36.

Each fur 38 has a frustoconical general configuration. The end of the fur having the smallest dimensions is turned towards the body 18. This end is advantageously substantially at the mouth of the anchor plate 28 or recessed therefrom in the anchoring orifice 36. In other words, this end does not protrude from the anchor plate 28 towards the body 18. At this end, the fur 38 has an inner diameter for example between 14 and 21mm.

The end region of the fur 38 is optionally bevelled at the inner face of the fur to obtain the desired size.

The fur 38 has a frustoconical outer face of complementary shape of the frustoconical inner face of the anchoring orifice 36, and a frustoconical inner face of complementary shape of the frustoconical outer face of the jaw 30. Each fur 38 is removable and can be arranged on the associated strand by lateral engagement before placing the jaw 30 or at the same time as this one. The fur may also be formed by assembling several (for example two or three) segments each covering an angular sector of the frustoconical shape.

The furs 38 are advantageously made from metal, for example steel to support the strangling force of the strands.

Alternatively, the furs 38 are not used. In these configurations, the jaw 30 which cooperates with the strand 12 passing through the anchoring port 36 is in direct contact with the anchoring port 36 (i.e., the anchor plate 28). . The two configurations may be used together, for example one being implemented for one of the anchoring devices 20, and the other for the other device 20.

The retaining plate 32 prevents the withdrawal of the jaws 30 from the anchoring holes 36 of the anchor plate 28. Such a withdrawal can occur for example in case of accidental overvoltage or dynamic effect in a portion B. In addition, the retaining plate 32 contributes to the leveling of the jaws 30.

For this purpose, the retaining plate 32 is located facing the front surface of the anchor plate 28. It is disposed against the rear ends of the jaws.

For example, the retaining plate 32 is made of plastic. In some configurations, it is made of thermostable plastic material, such as polyetheretherketone, PEEK ("PolyEtherEtherKetone"). Its section covers all the jaws 30 of the adjacent anchor plate 28.

The retaining plate 32 comprises a passage for each strand 12. These passages are aligned with the anchoring orifices 36. Advantageously, they are dimensioned so that the strands do not come into contact with the retaining plate 32 during the course of life 10. For example, these passages have a diameter of between 16 and 23 mm.

In an alternative configuration, in place of the passages, the retaining plate 32 has a general comb configuration whose openings are configured for the lateral engagement of this plate on the bundle of strands 12 after threading the strands 12 in the anchor plate 28.

Still with reference to FIG. 3, the housing 26 formed in the tubular casing 22 of each anchoring device 20 advantageously encloses a sealing system 40 adapted to seal the saddle 10, and a guide member 46. The sealing system 40 may be of the stuffing box type, with a deformable seal 42 sandwiched between the guide member 46 and a support plate 44. The compression of the seal 42 by axial compression seals the housing 26 and thus prevents the penetration of water into the environment of the anchoring device 20 and into the ducts 24.

Advantageously, the support plate 44 is located between the seal 42 and the retaining plate 32. The support plate 44 is for example made of metal, such as steel. It includes a passage for each strand.

The seal 42, for example made of neoprene, also comprises passages aligned to receive the strands.

The support plate 44 is for example displaceable in the housing 26 to compress and deform the seal 42, for example via one or more clamping screws accessible from the front face of the saddle 10 (not shown).

In another embodiment, the support plate 44 is in a fixed position, with its rear face in contact with the front face of the retaining plate 32. In this case, the compression of the seal 42 is operated by pushing the organ deflection 46 to the inside of the tubular casing 22.

Still with reference to Figure 3, the guide member 46 is configured to guide the strands 12 in the portion B at the approach of the saddle 10, in particular by allowing angular deflections. The guide member 46 also contributes to compressing the seal 42 together with the plate 44.

The guide member 46 comprises a plurality of guide channels 48 each provided for receiving and guiding a strand 12. By guiding means here that the strands 12 are adapted to come into contact with the walls of the channels 48.

The guide channels 48 are aligned with the passages of the seal 42, themselves aligned with the anchoring orifices 36 and with the conduits 24.

Each guide channel 48 has a flare towards the current portion of the stay formed by the corresponding portion B, as described in EP 1 181 422 B1. This flare is for example designed to accommodate the angular deviations of the strands 12, in particular the dynamic deviations, resulting for example from vibrations of the stay under the effect of the wind, the passage of vehicles on the bridge, etc.

The guide member 46 is for example made of HDPE. Still with reference to FIG. 3, the saddle 10 comprises, for each of its ends, a fixing device 50 configured for fixing the portion 111 of the sheath 11 to the saddle 10. Each fixing device 50 is also configured to maintaining the anchoring device 20 located at this end of the saddle 10 in the corresponding housing 26.

Each fixing device 50 comprises an attachment module 52 configured for fixing the sheath portion 11 associated with the saddle 10.

This module 52 advantageously includes a flange 53 defining a space for receiving and holding in place a portion of the connection sleeve 11C of the sheath 11 bearing against the saddle 10. The portion in question corresponds for example to a peripheral collar arranged at the end of this connection sleeve 11C. The flange itself is for example screwed into place in the pylon.

Advantageously, the fixing module 52 further comprises a bearing element 55 forming a counter-flange for the flange 53. This bearing element 55 bears against the face of the corresponding pylon, and the sleeve 11C of the sheath 11 is engaged between the flange 53 and this support element. This element 55 is for example in the form of a lip or a flange applied against the face of the pylon.

The support element 55 is advantageously part of the envelope 22 itself, at the end of which it is located.

The fixing device 50 further comprises a plate 54 against which the anchoring device 20 bears in order to hold it in the housing 26. For example, it is the guide block 46 which bears against the plate 54.

This plate 54 is located at the corresponding mouth of the envelope. For example, it is outside the envelope 22.

This plate 54 is for example held in place by the flange 53 together with the end of the sheath 11. For example, it is then in contact with the bearing element 55. Alternatively, it is in direct contact with the pylon.

This plate 54 advantageously has an annular configuration defining a central opening for the passage of all the strands 12.

Alternatively, this central opening is replaced by perforations located opposite the guide channels 48 and which have a diameter greater than or equal to that of the channels 48 at their mouth facing the plate 54. Optionally, the region of the face of the tower 8 where there is a fixing device 50 has a reservation in which the fixing device 50 is housed. This reservation can be configured to prevent water runoff against the outer face of the fastener 50.

With reference to FIG. 3, the housing 26 is therefore delimited longitudinally by the plate 54 and the body 18 and radially by the envelope 22. The anchoring device 20 is held in place in the housing by the support of the plate 54 against the guide member 46, which itself bears against the seal 42, which itself bears against the clamping plate 44, which itself bears against the retaining plate 32 (optional), which takes it bears against the rear side of the jaws 30 engaged in the frustoconical orifices 36 of the anchor plate 24, which itself bears against the body 18. The assembly of the guide member 46 can be completed by screwing on the anchor plate 28 through the gland. This screwing is for example achieved by through screws (not shown).

In the context of the invention, for at least one anchoring device 20, and advantageously for both, the sheath 16 of a given strand 12 is removed on a portion of the strand noted 12P which is received in the orifice. anchoring 36 and which extends on either side of the anchoring orifice 36. It is at this portion 12P that the jaw 30 is engaged with the strand 14 of the corresponding strand.

This portion 12P advantageously has a length less than three times the length Lm of the jaws 30. It has for example an end located in the thickness of the seal 42, and an opposite end in the conduit 24 of the body 18.

In this configuration, the stripped portion 12P of the strand 14 is directly received in the seal 42, the support plate 44, the retaining plate 32, the anchor plate 28 and the beginning of the corresponding conduit 24. Advantageously, with the exception of the anchoring plate 28 at which the strand 14 is in contact with the jaws 30, the strand 14 remains spaced from the other structural elements of the anchoring device 20, in particular the walls of the passages in which portion 12P is received.

Along the portion 12P, a protective material 56 is brought into contact with the stripped strand 14, to protect the steel of the strands 14 against corrosion, as well as the other metallic elements of the anchoring device 20.

Advantageously, this product has lubricating properties. It is for example a fat, a wax or a gel having equivalent properties. The protective material 56 is for example injected into the housing 26. The ducts 24 are advantageously each provided with an O-ring 57 at the end of the portion 12P to prevent the penetration of the material 56 further into the conduit 24 .

The seal 42 further prevents leakage of the material 56 from the housing 26 once it is deformed.

A method of deflecting a stay using the seat 10 according to the invention will now be described with reference to Figures 4 and 5.

A first step consists in molding the body 18 of the saddle 10 in the manner indicated above, the BFHUP or other moldable material sufficiently strong, is injected into the space defined by the tubular envelope 22, the walls 34 against which will come s The anchoring plates 28 are supported on either side of the body 18, and the elastomeric molding elements corresponding to the ducts 24. After taking the BFUHP, the elastomer molding elements are extracted by pulling.

This step of molding the body 18 does not need to be performed on the site of the book. The envelope 22 and the body 18 may be prefabricated at the factory. It is conceivable that the body 18 is formed with the casing 22 without molding operation, although the molding is the most convenient and reliable method for controlling the interface that the ducts 24 provide to the sheathed strands 12. If the body 18 is prefabricated, it is hoisted to its location on the pylon before installation of the stay 4.

Once the stay 4 has been raised to the location of the saddle 10 on the pylon 8, each strand 12, provided with its individual sheath 16 over its entire length, is threaded through a portion 111 of the general sheath. 11 of the stay, its conduit 24 formed in the body 18 of the saddle 10, as well as the components of the anchoring devices 20, then in the other portion 11 ₂ of the general sheath 11 of the stay. At the level of the saddle 10, the strand 12 is threaded into these elements in the order that they are intended to have once the seat completed, namely:

• guiding member 46 of a first anchoring device 20 on one side of the pylon 8;

Seal 42 of the sealing system 40 of the first anchoring device;

• support plate 44 of the sealing system 40 of the first anchor;

• retaining plate 32 of the first anchor;

Anchoring plate 28 of the first anchoring device; • molded body 18 of the saddle;

Anchoring plate 28 of a second anchoring device on an opposite side of the pylon 8;

• retaining plate 32 of the second anchor;

Support plate 44 of the sealing system 40 of the second anchoring device;

Seal 42 of the sealing system 40 of the second anchoring device;

Guide member 46 of the second anchoring device 20.

It may be possible to place also the jaws 30 and / or their furs 38 around the strands 12 between their threading in the retaining plate 32 of one or the other of the anchoring devices 20 and their threading into the plate of associated anchoring 28, if the jaws allow the untightened state to receive the strand 14 provided with its sheath 16.

Beyond the saddle 10, the strands 12 of the stay 4 are slipped collectively into the second section of the sheath 11 to descend to the second end of the course of the stay. At this stage, the sheaths 11 on either side of the pylon 8 are spaced from it, as well as the guide members 46, the joints 42 not yet compressed, the support plates 44 and the retaining plates 32, in order to make the housing 26 accessible and to free up sufficient space to carry out the anchoring using the jaws 30.

The ends of the strand 12 are temporarily anchored at the ends of the stay 4, for example at the deck 6, a roof, a retaining mass, etc.

The individual sheath 16 of the strand 12 is removed on its two portions 12P (one for each anchoring device 20), so as to strip the strand 14.

The strand 12 is then tensioned at its temporary anchors. For example, this tensioning is performed substantially simultaneously at its two active anchors at the ends 4E of the stay.

The tension in the strand 12 is brought to a tension corresponding to the chosen prestressing tension. This value is for example between 0.5 and 0.7 FRG ("Guaranteed Ultimate Tensile Strength") of the strand. For example, this tensioning is implemented by a standard device for stressing strands, such as a hollow monotoron jack.

Then, the strand 12 is anchored in the anchoring plates 28 of the two anchoring devices 20 so that the voltage applied to the strand 12 in the previous step equals at the prestressing tension, will remain in the portion A located in the body 18 permanently.

In each of the two anchoring devices 20, the jaws 30 are assembled around the strands 12 (if they have not already been put in place when threading the strands), as well as their furs 38 if it is provided, then driven into the orifices 38 around the stripped portions 12P. Each jaw can be unlocked in this configuration by applying a calibrated pressure.

The overblocking consists in applying a force on the rear of the jaw 30 configured to make the jaw penetrate into its anchoring orifice 36, beyond the mere penetration induced by passive locking of the jaw.

This blocking makes it possible to prevent or significantly limit an undesirable additional penetration, sometimes known as the "passive jaw entry", of each jaw 30 in its anchoring orifice 36 during the relaxation of the tension force applied to the anchors. each strand 12 in the next step.

A device 58 as illustrated in FIG. 5 can be used to overlock the jaws

30.

The device 58 comprises an overblocking chair 60 fixed to the saddle 10 and provided with one or more jacks 62 intended to press on the jaw 30 for its locking in the anchoring orifice 36.

Advantageously, this connection is implemented via the retaining plate 32 close to the housing 26 and an overblocking spacer 63 interposed between the retaining plate 32 and the jaw 30 to transfer to the jaw 30 the force generated by the jacks 62 and thus press the jaw 30 into the anchor hole 36.

The retaining plate 32 can be fixed to the chair 60 by a plate 64 connected to the cylinders 62.

During this step, the support plate 44 can be placed against the retaining plate 32, the chair resting on the retaining plate 32 via the support plate 44.

The overblocking spacer 63 has for example a generally cylindrical hollow shape within which the strand 12 is received. It is adapted to be attached to the strand by lateral engagement and to be released also laterally. It may have a section in Y, that is to say with a region of general configuration of V or U supplemented by a dorsal rib extending from the central part of this region. This rib increases the bending stiffness and the bearing section on the plate 32. The device 58 is advantageously fixed to the saddle 10 via the fixing device 50, the sheath 11 not yet being fixed thereto.

Once the jaw 30 is ready to be unblocked in its anchoring hole 36, the jacks of the device 58 push the retaining plate 32 towards the anchoring orifice 36, which presses the jaw 30 into the anchoring orifice under the effort allotted to him by the spacer 63.

The cylinders 62 are then released, the plates 32 and 44 are moved back and the spacer 63 is disengaged from the strand 12. The jaw 30 remains anchored firmly in place in its anchoring orifice 36 under the effects of the constant tension prevailing in the portion A and the overblocking operation.

The device 58 is kept in position until installation of the last strand, as described below.

The overblocking of the two jaws associated with the strand 12 has the effect of freezing the tension in the portion of the strand located between the two anchoring devices 20 to the prestressing tension, which will then remain substantially constant.

The overblocking operation can be carried out strand by strand, group of strands by group of strands, or collectively for all the strands 12 of the strut 4. It may possibly be sufficient to perform this operation on only one side of the pylon 8.

Then, the temporary anchoring of the ends of the stay 4 is released, then the ends of each strand 12 are anchored in their permanent anchoring to the desired tension in the portions B. For each strand, this tension, for example between 0.2 and 0.6 FRG, is lower than the prestressing tension in the A portion.

The device 58 is disassembled before or after completion of the final anchorages of the ends of the stay 4.

For each of the first and second anchors 20 on either side of the pylon 8, the retaining plate 32 and the clamping plate 34 are placed in the housing 26, as well as the seal 42 and the guide member 46. The portions 111, 11 ₂ of the sheath 11 can then be fixed to the saddle 10 via the fixing devices 50.

During this fixation, the plate 54 presses on the guide member 46 which compresses the seal 42 and seals the internal volumes of the saddle 10.

The protective material 56 is injected into the housings 26 on each side of the pylon 8, so that it protects the strands 14 of the strands 12 on the 12P portions that are missing. For the injection, it is possible to use openings 70 formed in the casing 22 radially at the level of the housing 26, for example in line with the retaining plate 32.

The invention avoids the use of couplers for the strands at the pylon, which couplers are bulky, expensive devices whose mechanical strength (in particular dynamic) can be critical, and which require to make delicate arrangements for guarantee their good protection and that of the strands vis-à-vis corrosion.

The provision of the anchor plate 28 bearing against the body of molded material 18 prevents this plate 28 is subjected to bending forces in operation. The anchor plate 28 can therefore be relatively thin and thus allow the production of a compact saddle 10 that extends only a little, if at all, on the surface of the pylon 8, even if a sealing system 40 and a guide member 46 can be integrated therein. The invention thus optimizes the mechanical performance of the saddle while keeping it compact. It can not form any protrusion on the pylon 8, which is satisfactory from the aesthetic point of view.

The embodiments described above are a mere illustration of the present invention. Various modifications can be made without departing from the scope of the appended claims.

Claims

An assembly comprising: a structural cable (4) having a plurality of tensioned strands (12) anchored at two opposite ends (4E) of the structural cable between which they extend continuously; and a saddle (10) configured to deflect the structural cable between its two ends, wherein the saddle (10) comprises: a body (18); a plurality of conduits (24) formed in the body and each receiving and guiding one of the strands; and two anchoring devices (20) configured to anchor the strands to define a first portion (A) of the structural cable received in the saddle where the strands are subjected to a substantially constant prestressing tension over time, and at least a second portion (B) of the structural cable where the strands are subjected to varying voltages over time, wherein at least one of the two anchors (20) comprises: an anchor plate (28) having anchoring ports (36) each receiving one of the strands, the anchor plate (28) having a rear surface bearing against the body; and jaws (30) each received in a respective anchor hole of the anchor plate to block one of the strands of the structural cable.

2. The assembly of claim 1, wherein the body (18) is made of a material molded inside a tubular casing (22) of the saddle (10).

3. An assembly according to any one of the preceding claims, wherein each strand (12) of the structural cable is coated with an individual sheath (16) removed at the anchoring device (20), wherein the orifices anchoring (36) are frustoconical in shape through the anchor plate (28), and in which the frustoconical shape has a minimum diameter strictly greater than the diameter of the strand (12) coated with the individual sheath (16).

4. The assembly of claim 3, wherein at least one of the anchoring holes (36) receives a fur (38) surrounding the jaw (30) to define in the anchor port a passage of smaller section than the anchoring port, through which a strand (12) passes through the anchor plate.

5. The assembly of claim 3, wherein, for at least one anchoring orifice (36), the jaw (30) is in direct contact with the frustoconical wall of the anchoring orifice to anchor the strand (12). ) in the anchor plate (28).

6. An assembly according to any one of claims 3 to 5, wherein at the anchoring device (20), the individual sheath (16) of each strand is removed on a portion (12P) of length less than three times the length of the jaw (30).

7. An assembly according to any one of the preceding claims, wherein the anchor plate (28) has a thickness of between 1 and 1.5 times the length (Lm) of the jaw (30).

8. An assembly according to any one of the preceding claims, wherein the saddle (10) comprises at least one guide member (46) comprising a plurality of guide channels (48) each receiving a strand (12) and configured to guide the angular displacements of the strands (12) in at least a second portion (B) of the cable.

An assembly according to any one of the preceding claims, wherein the saddle (10) comprises a sealing system (40) including an axially compressed seal (42) for sealing around the strands (12), the sealing plate anchoring (28) of one of the anchoring devices (20) being located between the sealing system (40) and the body (18) of the saddle (10).

10. The assembly of claim 9, wherein the saddle (10) comprises at least one guide member (46) comprising a plurality of guide channels (48) each receiving a strand (12) and configured to guide the angular deflections of the strands (12) in at least a second portion (B) of the cable, and wherein the sealing system (40) is placed between the guide member (46) and the anchor plate (28) of said anchoring (20).

An assembly according to claim 9 or claim 10, wherein an O-ring (57) is placed in each conduit (24) formed in the body for receiving a strand (12) of the structural cable (4), and wherein a protective material (56) is injected into a volume sealed by the axially compressed seal (42) and O-rings (57) and containing the anchor plate (28) and the jaws (30).

12. The assembly of claim 11, wherein each strand (12) of the structural cable is coated with an individual sheath (16) removed in a region between the O-ring (57) and the axially compressed seal (42).

An assembly according to any one of the preceding claims, wherein the anchor plate (28) has its rear surface bearing on the body (18), a front surface and a peripheral surface freely received in a housing (26). coaxial with the structural cable (4) at the anchoring device (20).

A method of deflecting a structural cable having a plurality of tensioned strands (12), the method comprising: providing a seat body (18) in a region between two ends (4E) of the structural cable (4) the body being formed with a conduit (24) for each strand of the structural cable; engaging each strand (12) in an anchor hole (36) of a first anchor plate (28) in one of the conduits (24) formed in the body (18) and then in an anchor port a second anchor plate; tensioning the strands at a predetermined prestressing tension in a first portion (A) of the structural cable between the first and second anchor plates and blocking the strands in each of the first and second anchor plates, while the first and second anchor plates second anchor plates (28) each have a rear surface bearing against the saddle body (18); and anchoring the structural cable (4) at both ends so that the strands (12) are subjected to varying voltages over time in two second structural cable portions (B) each located between one end of the cable structure and one of the first and second anchor plates (28).

15. The method of claim 14, wherein each strand is successively threaded in a guide channel (48) of a guide member (46) of a first anchoring device (20), in a passage formed in a sealing system (40) of the first anchor device, in the first anchor plate (28) belonging to the first anchor device, in one of the conduits (24) formed in the body (18), in the second anchor plate belonging to a second anchoring device, in a passage formed in a sealing system of the second anchoring device and in a guide channel of a guide member of the second anchoring device.

A method according to claim 14 or claim 15, wherein each strand (12) of the structural cable (4) is coated with an individual sheath (16), and wherein after strand engagement in an anchor port (36), the individual sheath of the strand is removed at said anchoring port to insert a jaw (30) blocking the strand.

17. A method according to any one of claims 14 to 16, wherein after tensioning the strands (12) in the first portion (A) to the prestressing tension and locking in the first and second anchor plates (28). ), the tension is released and the strands are tensioned in each second portion (B) to a value lower than the prestressing tension before anchoring the structural cable (4) at its two ends (4E).

18. A method according to any one of claims 14 to 17, wherein the tensioning and locking of the strands (12) in one of the first and second anchor plates (28), located at the rear of a housing (26) formed in a tubular casing (22) receiving the saddle body (18), comprises: applying a tension over the entire length of at least one strand (12); ) at at least one of the ends (4E) of the structural cable (4); arranging an overlock device (58) comprising at least one jack (62) on a front side of the housing (26); and actuating the jack (62) for, around said strand, driving a jaw (30) into an anchor hole (36) of said anchor plate (28).