FR2572435A1 - Machine and method for the formation of earth works reinforced with textile yarns - Google Patents

Abstract

The invention relates to a machine for the formation of reinforced earth works formed by a three dimensional mixture of a granular material and of textile yarns. The machine comprises: a motorised tractive vehicle 1 with orientable jib 2, provided with means for bringing the granular material loaded near the ground to the end of the jib, means 9 installed at the head of the jib for spraying the granular material in an accelerated stream, devices for ejecting the textile yarns, directing the yarns towards the layer of earth works being formed and means for synchronising the stream of material and the ejected yarns. The invention applies to the formation of reinforced earth works.

Description

 The subject of the invention is essentially a machine for forming reinforced grounds, formed of granular material and suitably entangled textile threads. The invention also relates to a method for forming reinforced terrains using such a machine.

 There is known, as described in particular in European patent No. 80,400,379.6 of March 21, 1980, a process for forming reinforced grounds consisting essentially of a three-dimensional mixture of a granular material and of textile threads suitably entangled in the mixture.

Tests have shown that such a material actually exhibits good qualities of resistance and cohesion, for example, by using unequal proportions of textile threads and granular materials of
around 1.5 per thousand, using threads with, for example, a titer of 330 decitex. (It is recalled that a thread having a titer equal to 1 tex has a weight of 1 gram per 1000 meters).

 As attractive as the process may be, it appears that there is no machine on the market allowing an efficient and economical implementation of the process consisting in intimately mixing a granular material such as sand with tangles of suitably distributed wires. and tense.

 Consequently, an essential object of the invention is to create such a machine.

 Another object of the invention is a method of forming terrains according to a procedure adapted to the new machine of the invention.

A machine according to the invention is characterized, in particular, in that it comprises
- a motorized tractor vehicle equipped with at least one boom which can be oriented in elevation and in deposit, provided with means for bringing the granular material loaded to the vicinity of the ground substantially at the end of the boom,
- means mounted at the head of the arrow ensuring the projection of the granular material according to an accessible jet
Managed,
- textile yarn ejectors mounted in the vicinity of the boom head and directing yarns towards the layer of ground in formation,
- Synchronization means sweeping in alternating movement movements substantially the same layer of ground by said jet and by said projected son.

 In this way, the granular material and the wires can be immediately deposited in layers at the work site, for example against an embankment or a cliff, the towing machine being at the foot of the structure and depositing the layer in formation directly at the level of this layer. The machine makes it possible to operate in successive layers, and the combined projection systems of the granular material and the wire avoid any problems of accessibility to the ground to be formed or to be propped up.

 It thus appears that the new machine designed according to the invention will allow the easy construction of embankments, reinforcements of work, widening of ways, consolidation of cliffs or shoulders not very accessible, etc ...

 According to another characteristic of the machine according to the invention, the means for projecting the granular material preferably comprise means for picking up and accelerating in a jet of the granular material, and adjustable deflector means forming a shield placed on the path of the jet.

The means of recovery and acceleration may include:
- an endless belt conveyor rotating at high speed,
a feed chute of said mat receiving the granular material arriving at the end of the boom, and
- Means for suspending and orienting the assembly formed by said chute and by said mat at the end of said arrow.

Advantageously, the wire ejectors are mounted on at least one orientable ramp, and said ramp, as well as the aforementioned deflector means are connected by a mechanism with articulated arms, which mechanism is actuated in alternating angular sweeping movements, of adjustable amplitude, by an engine mechanism with connecting rod and adjustable lever arm or equivalent
In this way, it is possible to adjust at any time the depth of the layer in formation, that is to say the thickness of the wall at the level of the layer concerned, by a simple combined adjustment of the amplitude of the alternative oscillation movements of the deflector shield of the granular material and the wire ejection ramps.

According to another important characteristic of
The invention, the ejectors are mounted oscillating about axes oriented obliquely to the direction of oscillation in sweep of the ramp of the ejectors, and the frequency of oscillation of the ejectors is adjusted so that the speed of movement on the ground projection of the ejector is greater than the speed of projection of the wire through the ejector. In this way it is ensured that the fit is deposited in the layer of granular material while still being stretched so that one will be assured of an immediate cohesion of the mixture.

 The process for forming reinforced terrains using a machine of the aforementioned type is characterized in that one proceeds by starting from the bottom and finishing at the top of the embankment to be formed, in successive layers of a few centimeters thick, which are superimposed to each other by scanning for each layer the entire depth of the embankment to be formed by suitable adjustment of the combined scanning angles of the deflector and of the injector ramp, an entire layer is formed, over the determined intervention length, by displacement of the towing vehicle at the foot of the slope to be formed, and as the slope rises, the inclination in elevation of the boom and that in bearing is modified to work in the best conditions, while remaining at the foot of the slope.

The invention and its implementation will appear more clearly with the aid of the description which follows, made with reference to the appended drawings in which
FIG. 1 shows from the side, schematically, the assembly of a machine according to the invention with the tractor vehicle and its boom,
- Figure 2 shows, front view and schematically, the machine with its arrow in the working position for the constitution of a reinforcement or widening slope,
FIG. 3 is a view on a larger scale of a part of the machine being executed for work in the region generally surrounded III in FIG. 2,
FIG. 4 schematically shows a method of mounting the device for high-speed projection of the granular material at the end of the boom of the machine,
FIG. 5 shows schematically and seen in the direction V of FIG. 4, the mechanical connection means ensuring the combined sweeping movements of the depth of the layer deposited for the granular material and for the textile threads,
FIG. 6 is a perspective diagram showing the relative positions of the various mobile members of the machine serving to deposit the granular material and the wires,
FIG. 7 is a schematic view from above of the ramp of the wire ejectors,
FIG. 8 schematically shows how the individual ejectors of the wire ejectors mounted on a ramp are carried out,
FIG. 9 shows more precisely how an ejector head is made up with its Latin eyebrow axis,
- Figure 10 shows the ejector head of Figure 9 according to section XX of this figure, and on a larger scale
- Figure 11 shows schematically the traces on the ground of the son ejection heads when they oscillate around their individual axes assuming stopped the overall oscillation of the ramp.

 The invention will now be described with reference first to Figures 1 to 3.

 The machine essentially comprises a motorized tractor vehicle 1 equipped with at least one boom 2 which can be oriented both in elevation (vertically) and in bearing (horizontally). In Figure 2 a site angle has been identified and marked in 3 the vertical axis around which the arrow 2 can be oriented in bearing. These two degrees of freedom allow easily, without having to move the tractor too frequently on the path 4 at the bottom of the slope 5 to be reinforced, to reach the working region as generally surrounded in III in FIG. 2.

 The jib 2 further comprises means, such as for example a conveyor belt or squeegees of all known types making it possible to bring to the end 6 of the jib the granular material, for example sand, which can be loaded into a storage hopper 7 suitably supplied, for example by bucket vehicles 8. The weight flow rate of the granular material is controlled in any known conventional manner.

 At the head of the arrow, the machine comprises means, identified as a whole 9 ensuring the projection of the granular material according to an accelerated jet, in the direction of the layer to be formed, and as will be explained in detail below.

 The machine also includes textile yarn ejectors identified as a whole 10 in FIG. 3, mounted in the vicinity of the end of the boom and directing yarns towards the layer of ground in formation.

 We will now describe the particular means of projecting the granular material ~, ejecting the wires and synchronizing these two operations, with particular reference to FIGS. 4, 5 and 6.

 We will first describe the means 9 for ejecting the granular material.

 These means are mounted towards the end 6 of the boom head 2 while being suspended freely by a hinge 11, for example of the ball-and-socket type below the end 6 of the boom head, the assembly being oriented relative to vertically 12 by means of a jack 13 whose foot 14 is articulated on the arrow 2 and the piston head 15 is articulated on the assembly 9.

Another jack 16 whose foot is articulated at 14 on the arrow 2 and whose piston head is articulated at 17 on the assembly 9 makes it possible to rotate the assembly 9 around the vertical axis 12, so as to direct this set according to the orientation in deposit desired to send the sand jet in the desired direction of the deposit.

The set 9 thus suspended comprises essential
a chute 18 which receives the granular material
re brought by the conveyor 19 at the top of the boom, and below this chute 18 a spraying device 20 of any known type, for example for the loading of grain vessels. As can be seen in FIG. 5, this projecting device 20 essentially comprises an endless belt conveyor 21 driven at high speed around two drive rollers 22, 23, a counter roller 24 forming on the top of the conveyor a hollow in which the granular material which falls at 25 is gradually accelerated in contact with the strip.

 ke granular material, for example sand, is thus ejected at the outlet of the device 20 in a jet 25 at high speed whose width corresponds to that of the carpet 21, and which can be for example of the order of 500 mm. This sandblast in the form of a flat thin strip strikes at high speed a deflector forming a shield 26 suitably suspended around a hinge pin 27 under the arrow 2. This shield, which may for example have a width of 600 mm (slightly greater than the width of the sand jet it receives) is driven in an oscillating movement around its axis 27 by means of a lever arm53 articulated around a fixed point 28 and at its other end 29 at the end of a connecting rod 30 connected to a crank 31 driven in rotation around - the axis 32 of a motor 33.

In addition, the length of the lever arm between the points
28 and 29 is adjustable by means of a cylinder 34, which
adjusts the amplitude of the oscillation angle d
of the shield.

It appears that the jet of sand which is
deflected on the shield 26 comes to form at the top of the
slope 35 a layer 36 of depth p (measuring the e
thickness of the wall built against the slope 5).

 The layer of sand thus deposited must be intimately married with tangled threads.

 To this end, the machine comprises, as mentioned above, a ramp of ejectors 10 of wires comprising for example five groups due to two heads of orthogonally crossed jets marked 40 to 49 in FIG. 6.

In the example illustrated, all the heads are mounted on a common rail 50, which can oscillate as a whole around a suspension axis 51 parallel to the axis 27 of oscillation of the shield 26. As it appears from your Figure 5, a link 52 connects the axis 28 of articulation of the arm 53 (between points 27-28) and a point of articulation 54 of the ramp 50. The geometry of the construction is thus chosen (ratio of homothety) ) that when the shield 26 describes an angulation of oscillation the ramp 50 describes an angulation of anglep, which angulation ensures, for each ejector 40 to 49 of the ramp, to come to cover the same depth g of the layer 36 deposited. '' other words, when we modify by modification of the length of the arm 34 the amplitude of oscillation we are sure that
The jet of sand projected by the device 9 and the jet of wires projected by the ramp 10 will cover the same depth 36 of ground.

 Of course, a counterweight 55 Figure 5) comes to balance the whole.

 Referring now more specifically to Figures 6 to 10, we see that in addition, we print on each ejector head 40 to 49 an oscillation around an axis oriented obliquely to the direction of oscillation station scanning of the ramp. In FIG. 7, the axes of oscillation of each ejector have been marked 60 to 69, and it can be seen that these axes are directed in pairs substantially orthogonally and obliquely with respect to the longitudinal axis 51 of oscillation of the ramp. 50.

 The osc; Llation of each ejector head around its axis can be obtained by means of a camshaft 70 driven by a motor 71, the cams driven by pushers and suitably oriented rods (not shown). in the drawings) the various heads in oscillation and synchronism.

 In FIG. 7, the traces which the ejection heads of the wires form under them when they oscillate these intersecting traces have been identified at 80 to 89 respectively.

 Figures 8 to 10 give a more precise idea of the oscillation movement of each ejector head. Referring to Figure 8, there is illustrated, for example, the oscillation of the head 40 by an angle Y around its oblique axis 60. The frequency of bone oscillation is chosen so that the speed of movement on the ground of the projection of the ejector is greater than the speed of projection of the wire through the ejector. More precisely, if the wire ejection speed is for example V1 = 20 meters per second, it is arranged so that, taking into account the distance D separating the ramp from the ground, the speed V2 of displacement of the trace t of the ejector on the ground is greater than this speed V1 of 20 meters per second. In this way, we are sure that the wire thrown into the mass of sand will be taut and not loose.

 If we refer to FIG. 11, we thus see the various traces 80 to 89 that the wires would leave on the layer in formation if we stopped the oscillation sweep / 3 of the ramp around its axis 51. In fact, taking into account this oscillation / 3, it appears that the threads are deposited according to a complex and regular entanglement while always remaining taut within the granular material.

 With reference to FIGS. 9 and 10, it can be seen that in practice each ejector is constituted by a head 90 receiving a supply of pressurized fluid, for example water 91 which is used to eject the wire 94.

The wire enters the head 90 through an eyelet 92 made of a material such as an alloy of aluminum and titanium reducing friction and it is entrained at 93 in the ejection nozzle of the ejector. The axis of oscillation of the ejector, such as the axis 60 if it is the ejector 40, is coincident with the axis of the inlet pipe 91 of pressurized water.

 From the foregoing description, it appears that the machine described is very flexible to use, since it is sufficient, by suitably adjusting the elevation and the location of the orientation of the boom to intervene in the desired area of construction of the structure. . The inclination of the deflector makes it possible to precisely specify the place that one wishes to cover and the amplitude of the oscillation d of the shield makes it possible to precisely adjust the depth p of the elementary layer that is formed. The thickness e of the layer is regulated by the flow of material and the speed of movement of the machine. The elementary length of the layer 1 corresponds substantially to the length of the shield and of the wire ejection ramp. The wire flow rate is adjusted according to the material flow rate and the weight choice that has been made of the proportions. The angle A of oscillation of the ejector boom is automatically adjusted as mentioned above to correspond to the oscillation of the shield. We are therefore assured of the correct arming of the layer e of material over its entire depth e. The entanglement of the wires in all directions is perfectly obtained by the double oscillations in opposite and orthogonal directions of the individual ejectors of the boom. By moving the machine at the bottom of the embankment, it is possible to process the entire desired intervention length by successively stacking the layers. The depth of the layer, i.e. the thickness of the formed wall is adjusted at each moment according to the final configuration that we want to give to the structure.

 In practice, the length of the arrow 2 makes it possible to have on each side of it, in two canters, a sufficient number of spools of son 94 to be able, without reloading the spools, to operate continuously for more than 10 hours.

Note that given the excellent quality and regularity of the deposits formed, it will be possible to work with further reduced percentages of textile threads compared to the granular material (sand or other) used
With a 25-tonne hydraulic shovel-type tractor machine, it is possible, for example, to deposit 30 tonnes per hour of suitably reinforced ground with a controlled dosage of wires that can vary between 1 and 2 teeming, by weight, depending on the desired qualities of the work and its conditions of use.

The thread flow rate can be easily adjusted at any time by adjusting the pressure of the ejector fluid.

 In addition, although the use of the machine has only been described in connection with the formation of a raised embankment, it is obvious that the machine can be used for other kinds of works, for example the construction of level embankments or embankments under construction, in trenches or other

Claims (8)

 1. - Machine for the implementation of a process for forming reinforced grounds formed of a three-dimensional mixture of a -granular material and suitably entangled textile threads in the mixture, said machine being characterized in that it comprises ::  a motorized tractor vehicle (1) equipped with at least one boom (2) orientable in elevation and in deposit, provided with means (19) for bringing the granular material loaded near the ground substantially to the end of the boom,  means (9) mounted at the head of the arrow ensuring the projection of the granular material according to an accelerated jet,  - textile yarn ejectors (10) mounted in the vicinity of the boom head and directing yarns towards the layer of ground in formation,  - Synchronization means sweeping substantially the same layer of ground by said jet and by said projected son.  2. - Machine according to claim 1, characterized in that said projection means (9) of granular material comprise  means (21-24) for picking up and accelerating the material in a granular jet, and  - adjustable deflector means (26) forming a shield placed on the path of the jet.  3. - Machine according to claim 2, characterized in that said recovery and acceleration means comprise  - an endless belt conveyor (21) rotating at high speed,  a chute (18) for supplying said mat receiving the granular material arriving at the end of the boom, and  - Means for suspension and orientation (11, 13, 16) of the assembly (9) formed by said chute and by said mat at the end of said arrow.  4. - Machine according to claim 2 or claim 3, characterized in that said son ejectors (40-49) are mounted on at least one orientable ramp (50) and said ramp, as well as said deflector means (26) are connected by a mechanism with articulated arms (52, 53, 34, 30) which is actuated in reciprocating angular movement of adjustable amplitude by a motor mechanism (33) with connecting rod (31) and lever arms (34) adjustable.  5. - Machine according to claim 4, characterized in that the ejectors (40, 49) are mounted oscillating about axes (60-69) oriented obliquely relative to the direction of the axis of oscillation (51) in ramp scanning (50).  6. - Machine according to claim 5 characterized in that the ejectors are mounted in pairs around axes oriented by crossing substantially ortho gona lement.  7. - Machine according to claim 6, characterized in that the oscillation frequency of the ejectors is adjusted so that the speed of movement on the ground (V2) of the projection of the ejector is greater than the speed (V1) of projection of the wire through the ejector.  8. - A method of forming reinforced terrains, in the form of an embankment, consisting of a three-dimensional mixture of granular material and textile threads by means of a machine according to one of the preceding claims, characterized in that proceed by starting from the bottom to finish at the top of the embankment to be formed, in successive layers of a few centimeters thick, which are superimposed on each other by scanning for each layer the entire depth t) by suitable adjustment of the angles of combined sweep of the deflector (26) and the ramp of the ejectors (50), an entire layer is formed over the determined intervention length by displacement of the tractor vehicle (1) at the foot of the embankment to be formed, and the as the slope rises, the inclination in elevation of the arrow (2) and that in deposit to work in the best conditions while remaining at the foot of the slope.