WO2013190052A2

WO2013190052A2 - Retaining structure, associated retaining device and device for preparing the edge of a ski slope using same

Info

Publication number: WO2013190052A2
Application number: PCT/EP2013/062910
Authority: WO
Inventors: Michel LEGON; Julien BAUD
Original assignee: Acro Btp
Priority date: 2012-06-21
Filing date: 2013-06-20
Publication date: 2013-12-27
Also published as: FR2992335A1; EP2864552B1; WO2013190052A3; EP2864552A2; FR2992335B1

Abstract

The invention relates to a retaining device structure (1) comprising: - an anchoring rod (3) intended to be driven into the ground of a slope in order to form an anchorage, - two criss-crossing metal bars forming a central cross (5), - four girders forming a pyramidal spike (7), said girders being arranged on the arms of the central cross (5), the tip of the pyramidal spike (7) pointing in the opposite direction to that of the end of the self-boring screw (3) intended to be driven into the ground, and having an orifice (71) through which the self-boring screw (3) passes, characterized in that it also has: - a frame (9) formed by girders, surrounding the central cross (5) and attached to the latter at the ends of the arms of the central cross (9). The invention also relates to the retaining device (100) using such structures (1) connected to one another, and to a device for preparing the edge of a ski slope (200) using such a retaining device (100).

Description

Supporting structure, associated support device and ski slope edge device using the same

The present invention relates to a retaining structure, in particular of the type used to prepare or reinforce earthworks and in the development of sloping terrain. The invention also relates to a support device obtained by adding structures, and to a ski slope edge layout using such a device.

It is known to use walls, stone, metal or wood generally, to create support structures. Such structures serve, for example, to retain soil in a sloping terrain, so that a strip of flat terrain can be constructed, especially for building a road or a building.

These earthworks structures are subject to strong constraints, due to the weight of the earth retained, and the structures must be designed to resist.

A well-known example is the retaining wall, also known as the retaining wall. Such a wall is usually built of stone, concrete, or metal sheet piling in a slope. The earth is held behind the wall, and presses against it in an effort that tends to push the wall and to tilt it.

It is known for example to anchor the retaining wall to one or more dead bodies, to associate a cantilevered sole, to add buttresses or to push a portion of the wall into the ground to resist to the efforts mentioned above, when the weight alone of the wall is no longer sufficient.

However, these methods are expensive in terms of resources and money, and often laborious to implement. For example, sheet piles require vibrators or pistons to be depressed. Dead bodies for anchoring must, if they are not naturally present, be moved and buried properly, and cantilevered soles must also be buried deep enough to play their part.

In order to at least partially meet the previously mentioned need, the subject of the invention is a support structure, comprising:

- An anchor rod, intended to be driven into the ground of a slope to form an anchor,

- two intertwined metal bars, forming a central cross,

- four beams, forming a pyramidal point, arranged on the branches of the central cross, the top of the pyramidal point pointing in the opposite direction to that of the end of the anchor rod intended to be driven into the ground and comprising an orifice through which the anchor rod passes, characterized in that it further comprises:

- A frame made of beams, surrounding the central cross and attached to it at the ends of the branches of the central cross.

The support structure thus obtained is feasible at lower cost, and can be implemented easily without the need for heavy equipment.

The retaining structure may further have one or more of the following features, taken alone or in combination.

The anchor rod, the central cross, the pyramidal tip, and the frame are made of steel.

The anchor rod may be a self-drilling screw, or a rod intended to be engaged with a dead body made of cement or concrete. It further comprises a retention layer disposed on the frame, preferably a metal grid welded to the frame.

It has a slash at each corner of the frame, and the ends of the branches of the central cross are attached to said slashes. The ends of the branches of the central cross are welded at a certain distance from the corners of the frame, on a straight portion of the beams forming the frame.

It comprises fasteners arranged on the frame, intended to engage with fasteners of a nearby retaining structure.

The invention also relates to the retaining device characterized in that it comprises a plurality of support structures as described above, wherein the retaining structures are connected by fasteners arranged on the frame.

In particular, for such a support device, the Support structures can be aligned in staggered rows.

Finally, the invention also relates to a device for skateboard edge arrangement comprising a support device as previously described, further comprising at least one panel attached to the upper edge of the frame of the structure or structures of support forming the upper line of the retaining device for retaining a snowpack.

Said device may then comprise vertical rods attached to the top of the pyramidal tip, to which is attached a safety net.

The lower edge of said safety net is then potentially attached by fast-opening rings to said at least one panel.

Other features and advantages of the invention will emerge more clearly on reading the following description, given by way of illustrative and nonlimiting example, and the appended drawings in which: FIGS. 1a, 1b, show, according to different views, an embodiment of a support structure, - Figure 2 shows an alternative embodiment of a support structure, Figure 3 shows the support structure of Figures la, lb, the installed state, the FIG. 4 shows a support device obtained from structures such as those of the preceding figures, FIG. 5 shows an alternative embodiment of structure retaining wall according to the invention. Figure 6 shows a runway edge layout device

In FIG. 1a, 1b, 1c is schematically shown a structure 1 of reinforcement of the ground according to the invention, respectively of face (Ia), of profile (Ib) and of three-quarters (Ie).

Such a support structure 1 comprises an anchor rod 3, a central cross 5, a pyramidal tip 7, and a frame 9.

The anchor rod is here produced as a self-drilling screw 3, partially visible in FIG. 1b is made of steel, in the form of a shaft with a thread. This self-drilling screw 3 is to be driven into the ground by one of its ends, in particular by screwing the thread into the ground by rotation of the shaft, which causes a tapping around the hole formed by the depression of the screw 3. This tapping retains the screw 3 once it is depressed.

The central cross 5 is composed of two intersecting metal bars, and carries the pyramidal point 7. Said pyramidal tip 7 has four beams, forming the edges of a pyramid whose base is in the plane of the central cross 5. The four - trelles meet at the tip of the pyramid, which is an orifice 71, in which is passed the self-drilling screw 3. The top of the pyramidal tip 7 points in the opposite direction to that of the end of the self-drilling screw 3 intended to be driven into the ground.

The screw 3 is retained in translation at the orifice 71, for example via a screw head of larger diameter or with the aid of one or more nuts.

Alternatively, the anchor rod 3 may be a rod, in particular solid, intended to be surrounded by cement or concrete. The rod 3 is then put in place in a prior drilling in which the cement or concrete has been injected, then allowed to take the cement or concrete, which then acts as a dead body. For better strength, the outer wall of at least the extremal portion of the rod 3 may be knurled, serrated or at least roughly frosted for better attachment of the cement or concrete.

The central cross 5 has at its center a bore 51, through which the self-drilling screw 3 is passed. This bore 51 contributes, with the orifice 71, to constrain the self-drilling screw 3.

In particular, the bore 51 contributes to the alignment of said screw 3 relative to the plane of the central cross 5, which is, at the establishment of the structure 1 in the framework of the support of a slope, arranged vertically, generally roughly aligned on a level line of the slope, ie perpendicular to the gradient of the slope.

In an alternative use, the structure 1 is used to reinforce a plumb, for example such as an embankment or a cliff above a road. The structure 1 is then pressed by the screw 3 against the plumb, and then allows to slow erosion and prevent landslides.

The four beams forming the pyramidal tip 7 are attached by their base to the metal bars forming the central cross 5, at an angle of 10 to 40 °, preferably 30 °, by welding. In particular, the metal bars forming the central cross 5 and the beams forming the pyramidal tip 7 are made of steel. These bars and beams may for example be segments of beams with square section, about ten centimeters of side, typical from 5 to 20 cm, hollow, with walls of a thickness of 3 to 10 mm.

Alternatively, these bars and beams may be H-section beam segments, with a central core and side wings (IPN type beam).

The pyramidal tip 7 protrudes from the plane containing the central cross 5, its vertex intended to point in the opposite direction to the ground retained once the structure 1 has been put in place, thus defining a front face of the structure 1, the screw 3 is thus directed towards the rear of the structure (buried side).

The connection between the bars forming the central cross 5 and the beams forming the pyramidal tip 7 may be reinforced by metal reinforcements 11, here in the form of metal plates, bent in their plane, the two sections of the elbow respectively coming against the bars and the beams, and being welded or screwed to them.

The frame 9 comprises four metal beams, assembled in a rectangle. The beams may in particular be of the same type as the beams of the pyramidal tip 7 and / or the central cross 5.

The frame 9 is connected to the ends of the branches of the central cross 5, which are here welded to him. In particular, the frame 9 is here elongated with respect to the central cross 5. In this way, the ends of the branches of the central cross 5 are welded at a distance from the corners of the frame 9, on a flat lateral surface of the beams forming the frame 9.

This configuration makes it possible to hold the ends of branch of the central cross 5 by means of a single weld, practiced in one piece over the entire section of the beam forming a central cross branch 5. Such a weld is more economical and stronger. The frame 9 can typically have a size of the order of three meters side, the other elements (pyramidal tip 7, central cross 5) are dimensioned accordingly. The self-tapping screw 3 is a length of several meters, adapted to the estimated depth of drilling for good performance and a diameter of a few centimeters, typically 2 to 8cm.

Figure 2 shows an alternative embodiment, in which the frame 9 has slits 13 in the corners, forming a lattice. The branch ends of the central cross 5 are then welded to said slashes 13. The slashes 13 may be portions of the same beam as those used for the rest of the structure 1.

Figure 3 shows the structure 1 of Figures 1a, 1b, in the installed state.

To carry out the installation, the structure 1 is placed approximately vertically (or inclined according to the desired plumb), the self-drilling screw 3 is pressed into the ground until a sufficiently hard layer 15 is reached, for example the underlying rock if it is accessible. The screw 3 is then partially inserted into said hard layer 15, and taps into it, which fixes it with respect to the hard layer 15. If the hard layer 15 is too hard to allow a direct depression, a pre-drilling can be performed before screwing screw 3, so that said screw 3 only practices tapping.

The structure 1 comprises a retention layer 17 arranged on the frame 9, the side facing the ground thereof. The retention layer 17 is advantageously a metal grid (stainless steel in particular) welded to the frame 9, and possibly to the central cross 5. Alternatively, said retention layer 17 may for example be a wooden panel, plastic or metal, which will then have to be pierced with holes for a flow of water. The space between the slope and the structure 1 is filled with embankment 19, for example earth, rubble, or sand.

The embankment 19 is retained by the retention layer 17, the resulting pressure is applied to the central cross 5 and the frame 9. This resulting pressure is counteracted by the self-drilling screw 3, in engagement with the hard layer 15, which transmits the reaction force via the pyramidal tip 7, whose beams transmit the forces to the central cross 5. The central cross 5 then transmits the forces to the frame 9. The pyramidal structure of the tip 7 here acts as a vault in the transmission efforts, so that they, starting from the orifice 71, are distributed over as large a surface as possible.

In particular, it is advantageous for the connection between the screw 3 and the orifice 71 to allow the adjustment of the length of the anchoring rod 3, which is the case with the nut or nuts and / or with a self-locking screw retained in translation. at the orifice 71. Indeed, by making it possible to shorten the length of the anchor rod 3 used, a prestressing of the ground behind the structure 1 is achieved by means of the forces transmitted during a shortening of the rod length of 3. This shortening can be achieved after the implementation of said structure 1 because of the accessibility of the orifice 71 located on the apparent face of the structure 1. This prestressing makes it possible to reduce an uncontrolled and subsequent settlement of the structure. retained soil, and / or to slow erosion by soil compaction. FIG. 4 shows a plurality of structures 1, implemented side by side, to form a retaining device 100.

The structures 1 are here aligned in rows, which are themselves arranged one on the other. The rows may in particular be shifted, with respect to the next one, so that the retaining structures 1 are staggered in the retaining device 100.

In particular, each structure 1 comprises fasteners 21, which are arranged on the frame 9 so as to engage with a supporting structure 1 neighbor, when said structures 1 are arranged side by side to achieve a tiling of the plane of steady to support.

These fasteners 21 are, in the examples shown pierced protruding tabs, in which is inserted a pin. Other embodiments may be envisaged, such as rings and associated hooks.

FIG. 5 shows an alternative embodiment of a retaining structure 1.

In this alternative embodiment, the orifice 71 at the top of the pyramidal tip 7 is articulated by means of a hinge 73. The bore 51 is carried by a sliding connection 53, movable along rails 55. The rails 55 comprise parallel metal bars, two in number and starting from the center of the central cross 5, welded to the frame 9, and forming a support for the bore 51 carried by a slidable plate along the parallel metal bars.

Due to the presence of the hinge 73 and the slide connection 53, the angle formed by the self-drilling screw 3 with the frame 9 and the -liera ix Central 5 can be adjusted. To maintain said angle, a holding orifice 57 is provided at the slide connection 53. By adjusting the self-drilling screw length 3 between the two orifices 71, 57, by means of, for example, a nut device and against nut, the angle between the self-drilling screw 3 and the frame 9 is adjusted. Alternatively, the orifice 71 and the bore 51 may comprise a thread that engages with the screw thread of the screw 3.

The embodiment shown also comprises feet 23, arranged on the side of the frame 9 intended to be in contact with the ground. These feet 23 can be adjustable in height to allow an adjustment of the height of the structure 1, and / or be provided with coatings and forms for better grip on the ground.

Such support structures 1 may in particular be used to prevent an avalanche, being arranged regularly on a slope before heavy snowfall. The retaining structures 1 thus arranged retain the snow which is then deposited in place of the embankment 19. It is then possible to influence the amount of snow retained by tilting the frame 9 (and hence the cross 5 and the point 7): if the retaining structure 1 is strongly inclined relative to the normal ground, it will retain only little snow but will be quickly covered, if on the other hand it is kept close to normal ground, it will be later covered but will retain a larger amount of snow. By modifying the inclination of the support structures 1, the volume of snow retained by the structures 1 can be adapted to the amount of snow expected.

The retaining structure 1 and the retaining device 100 according to the invention are easily installable, and in particular do not require heavy machinery for the insertion of supporting elements, in contrast, for example, sheet pile systems.

The retaining device 100 can therefore be installed in potentially more remote or difficult to access places, and / or at a lower cost.

The presence of the frame 9 and the fasteners 21 carried by it makes it possible to associate the structures 1 more easily and more solidly with one another to form the associated support device 100. Figure 6 shows a ski slope edge arrangement device 200 comprising a support device 100 as previously mentioned.

The runway edge arrangement 200 is intended to be implemented in the vicinity of said ski slopes at a level where the snow pushed by the skiers gradually falls out of the runway, resulting in premature closure. .

The arrangement device 200 comprises a support device 100, forming with the earth that it holds a plumb, marking in fact the limit of the track. In FIG. 5, the retaining device 100 comprises a single line of reinforcement structures 1, however, it is possible to produce a layout device 200 with several lines of structures 1.

The upper line of structures 1 limits the height of plumb, corresponding to the edge of the hard ground, without the snow. Said upper structural line 1 of the retaining device 100 carries bases 23 which carry vertical posts 25. These vertical posts 25 have two lateral notches, for example having an H section with a central core and side wings. Between the lateral notches of two consecutive posts 25, one or more panels 27 are inserted. The panel or panels 25 are intended to retain the snowpack 28 which is deposited on the embankment 19 behind the retaining structures 1.

The panels 27 are preferably of wood, of a height corresponding to the expected thickness of the snowpack 28. Advantageously, each panel 27 is composed of a plurality of longitudinal planks, which can be placed one above the other and removed to adjust the panel height 27 to that of the snowpack. The dimensions of such boards are, for example 225mm wide, 75mm thick and 4500mm long. If there is a significant fall or melting of snow, the number of boards stacked in height can be adapted by the trackers.

The upper edge of the panels may additionally be covered with a metal angle (not shown) to prevent contact with a snow groomer damaging the device 200. The arrangement 200 may further comprise a net 29, stretched by cables 33 above the panels 27, carried by vertical yards. The vertical yards are at their base integral with the top of the pyramidal tip 7.

The yards 35 are tubes, metal, plastic or polymers, a height of a few meters. Their lower portion is straight, while the upper portion is curved, so that the upper end of the penis 35 is vertical panels 27.

The arrangement device here further comprises arcs of reinforcement 37, which are arranged on the upper limit bar of the frame 9, the convex side outwards. The reinforcing arches 37 comprise at their top a rod attachment 39, which secures the rod 35 and the reinforcing arch 37. The reinforcing arches 37 strengthen the rods 35 in their position.

The safety net 29 is attached at its lower edge to the vertical rails 25. In addition, it is possible to include a system of tensioners for the safety net 29. For example, the vertical yards can be tensioned by flexion . To avoid the formation of a hole under the safety net 29 as it is formed in the simple net systems commonly used (with simply posts between which the net 29 is stretched), quick-opening rings, such as so-called pigtail hooks or hooks may be positioned at regular intervals on the panels 27, and a braided cable in the safety net 29 is then passed through said fast-opening and tensioned rings, for example by means of a jack.

By allowing a steeper plumb, the retaining device 100 of the runway edge layout device 200 makes it possible to widen said runway: an additional flat portion can be developed where, without support, the ground would collapse in a natural slope. .

In addition, the retaining structures 1 used to form the retaining device 100 form an appropriate base forming a support for the panels 27 and the safety net 29. The panels 27 retain the snow from the edges of the track, which is otherwise pushed progressively by the skiers to the outside, and the safety net 29 makes it possible to prevent a skier from falling into the formed plumb. by means of the support device 100.

The retaining device 100 is preferably implemented before the first snowfall and can remain in place after melting it for several years. The device can be used out of season for slopes with downhill biking or other means of locomotion, and slows down the erosion of the runway edge.

Claims

Retaining structure, comprising:

- An anchor rod (3), intended to be driven into the ground of a slope to form an anchor,

- two intertwined metal bars, forming a central cross (5),

- four beams, forming a pyramidal point (7), arranged on the branches of the central cross (5), the top of the pyramidal tip (7) pointing in the opposite direction to that of the end of the anchor rod (3) intended to be driven into the ground and having an orifice (71) through which the anchor rod (3) passes, characterized in that it further comprises:

- A frame (9) formed of beams, surrounding the central cross (5) and attached thereto at the ends of the branches of the central cross (9).

Structure according to claim 1, characterized in that the anchor rod (3), the central cross (5), the pyramidal tip (7), and the frame (9) are made of steel.

Structure according to claim 1 or 2, characterized in that the anchor rod (3) is a self-drilling screw.

Structure according to claim 1 or 2, characterized in that the anchor rod (3) is a rod intended to engage with a dead body made of cement or concrete.

5. Structure according to one of claims 1 to 4, characterized in that it further comprises a retention layer (17) disposed on the frame (9).

6. Structure according to claim 5, characterized in that the retention layer (17) is a metal grid welded to the frame (9).

7. Structure according to one of claims 1 to 6, characterized in that it comprises a slash (13) at each corner of the frame, and in that the ends of the branches of the central cross (5) are fixed to said slashes (13).

8. Structure according to one of claims 1 to 6, characterized in that the ends of the branches of the central cross (5) are welded at a distance from the corners of the frame (9), on a straight portion of the beams forming the frame (9).

9. Structure according to one of the preceding claims, characterized in that it comprises fasteners (21) arranged on the frame (9) intended to engage with fasteners (21) of a retaining structure (1). ) neighbor.

10. Retaining device, characterized in that it comprises a plurality of retaining structures (1), said retaining structures (1) comprising:

- two intertwined metal bars, forming a central cross (5),

- four beams, forming a pyramidal point (7), -indisposées on the branches of the central cross (5), the top of the pyramidal tip (7) pointing in the opposite direction to that of the anchor rod (3) and having an orifice (71) through which the rod passes anchoring (3),

- a frame (9) formed of beams, surrounding the central cross (5) and attached thereto at the ends of the branches of the central cross (5), in which retaining structures are connected by fasteners (21) arranged on the frame (9).

11. Device according to claim 10, characterized in that the retaining structures (1) are aligned in staggered rows.

12. A ski slope edge arrangement device (200), characterized in that it comprises at least one retaining device (100), comprising a plurality of retaining structures (1), said structures comprising:

- two intertwined metal bars, forming a central cross (5),

- four beams, forming a pyramidal point (7), arranged on the branches of the central cross (5), the top of the pyramidal point (7) pointing in the opposite direction to that of the anchor rod (3) and having an orifice (71) through which the anchor rod passes

(3) and attached thereto at the ends of the branches of the central cross (9), - a frame (9) formed of beams, surrounding the central cross (5) and attached thereto at the ends of the branches of the central cross (5), and further comprising at least one panel (25) attached to the upper edge of the frame (9) of the retaining structure (s) (1) forming the upper line of the retaining device, for retaining a snowpack (28).

13. Device according to claim 12, characterized in that it comprises vertical rods (35) attached to the top of the pyramidal tip (7), to which is attached a safety net (29).

14. Device according to claim 13, characterized in that the lower edge of the safety net (29) is attached by fast-opening rings to said at least one panel (25).