EP0803609B1 - Method for accurately placing an insert in concrete, apparatus for performing said method , and railway track obtained through the method - Google Patents

Abstract

The method for the precision placing of rail saddles (1) in concrete involves pouring a concrete slab (31) having a solid consistency and smooth surface. Whilst the concrete is fresh the saddle is driven in whilst vibrating with a vibrator (35) until the saddle attains the required position. A steel sheet base (30), laid on the concrete, has a circular opening on which a vertical tube (28) is welded. A polyurethane receptacle (28) passed through the tube has an internal surface fitting the shape of the saddle. During vibration the liquefied concrete is prevented from rising up the tube by the sheet and receptacle and forced into the insert cavities.

Description

The invention relates to civil engineering, in particular the construction of tracks railway. Indeed, this method is particularly advantageous for inserting, in a concrete slab, saddles supporting railway rails. It is also applicable in all cases where one seals in concrete, at a given position, with an accuracy of on the order of a millimeter, an insert which has at least one cavity which must be filled with concrete so that the insert can withstand significant stresses.

We know, from document DE 3714581, a process for the establishment correct reinforcement in a concrete slab into which we first introduce liquid concrete in a mold, then place the reinforcement on the concrete always liquid and the armature is brought into its correct position by vibration.

• couler une dalle de béton continue et lisser sa surface ;
• puis, pendant que ce béton est frais, enfoncer chaque barre de liaison dans le béton frais, en faisant vibrer la barre pour liquéfier le béton autour de cette barre pendant son déplacement, jusqu'à qu'elle atteigne une position donnée: les vibrations pendant le déplacement permettent un positionnement précis par rapport à une ligne de référence ;
• puis mettre en place un joint de dilatation qui coupe la dalle continue et la sépare en deux dalles qui restent reliées par les barres de liaisons.

EP 0 117 323 discloses a method for setting up, with precision with respect to a reference line, connecting bars between two concrete slabs, for making a motorway or an air strip. These bars are placed horizontally, and perpendicular to the plane of the expansion joint. This process consists of:

• pour a continuous concrete slab and smooth its surface;
• then, while this concrete is fresh, push each link bar into the fresh concrete, vibrating the bar to liquefy the concrete around this bar during its movement, until it reaches a given position: vibrations during the displacement allow precise positioning relative to a reference line;
• then install an expansion joint which cuts the continuous slab and separates it into two slabs which remain connected by the connecting bars.

Various methods are known for making a railway track. The ways more common are supported by sleepers placed on ballast. However we realize tracks without sleepers for particular applications, in particular for track tram in areas of road traffic. These tracks must be embedded in the pavement, and therefore require so-called disbursement earthworks. We minimize the depth of disbursement, to reduce costs and reduce inconvenience caused to residents and road users. For that, we realize tracks with a concrete slab instead of conventional sleepers. Rails rest on the concrete slab by means of metallic parts called saddles and rubber soles. The saddles are attached to the concrete slab, to transmit the efforts exerted by the passage of a tram on this track.

• solidariser deux rails en fixant manuellement des gabarits entretoises, réglables en altitude au moyen de vérins, pour définir l'écartement des rails et leurs altitudes respectives ;
• fixer manuellement des selles à intervalles réguliers sous chaque rail, entre les gabarits ; chaque selle comportant, sur une face, des goujons filetés permettant de fixer cette selle à un rail, et comportant, sur une autre face, des dispositifs d'ancrage aptes à être scellés dans du béton ;
• ajuster ces gabarits pour que le plan de roulement soit à l'altitude prévue et présente les pentes prévues ;
• poser des coffrages latéraux recyclables ;
• couler du béton sous les rails et le talocher, de telle sorte que les dispositifs d'ancrage des selles soient recouverts et noyés dans la dalle de béton, et que celle-ci présente une surface plane située juste en dessous des rails.

A known method for making such a route consists in:

• securing two rails by manually fixing spacer templates, adjustable in height by means of jacks, to define the spacing of the rails and their respective altitudes;
• manually attach saddles at regular intervals under each rail, between the templates; each saddle comprising, on one side, threaded studs making it possible to fix this saddle to a rail, and comprising, on another side, anchoring devices capable of being sealed in concrete;
• adjust these gauges so that the running surface is at the planned altitude and presents the planned slopes;
• install recyclable side forms;
• pour concrete under the rails and float, so that the saddle anchors are covered and embedded in the concrete slab, and that it has a flat surface located just below the rails.

This process requires great care to obtain precise positioning of the rails by the templates, and it requires time for mounting the spacer templates and for placing concrete. It is therefore costly in labor. Not being from industrial in nature, it leaves much to the initiative and know-how of the staff.

The object of the invention is to propose a method making it possible to carry out a railway track, without sleepers, at a lower cost than this known method.

• préparer un béton ayant une consistance ferme ;
• mettre en place ce béton, rectifier et lisser sa surface pendant qu'il est frais, pour donner à sa surface une position donnée, avec une tolérance donnée ;
• puis, pendant que ce béton est frais, déplacer l'insert dans ce béton, en faisant vibrer le béton autour de cet insert pendant son déplacement, jusqu'à qu'il atteigne une position donnée, avec une tolérance donnée ;

caractérisé en ce qu'il consiste en outre à confiner le béton par des moyens empêchant la remonteé de béton autour de l'insert pendant la mise en place de l'insert dans ce béton, pour forcer le béton à remplir chaque cavité de l'insert.The object of the invention is a method for placing an insert into concrete with precision, this insert comprising one or more cavities to be filled with concrete, consisting of:

• prepare concrete with a firm consistency;
• place this concrete, rectify and smooth its surface while it is cool, to give its surface a given position, with a given tolerance;
• then, while this concrete is fresh, move the insert into this concrete, vibrating the concrete around this insert during its movement, until it reaches a given position, with a given tolerance;

characterized in that it further consists in confining the concrete by means preventing the rise of concrete around the insert during the positioning of the insert in this concrete, to force the concrete to fill each cavity of the insert.

The process thus characterized makes it possible to use inserts comprising cavities relatively deep without the risk of improper filling. Therefore, it guarantees an anchorage very resistant to constraints. This property is particularly advantageous for inserts supporting railway rails.

• Le fait de faire vibrer le béton permet de le liquéfier momentanément au voisinage du point d'application des vibrations, autorisant ainsi un enfoncement aisé, un bon enrobage des parties noyées de l'insert, et de facto un bon scellement. Il est à noter que les vibrations peuvent être appliquées par l'intermédiaire de l'insert ou d'un autre dispositif indépendant de l'insert, et placé dans le béton, au voisinage de l'insert.
• Le fait que le béton soit mis en place en premier, qu'il soit lissé, et rectifié pour que sa surface ait une position relativement précise a pour effet qu'en enfonçant l'insert à une profondeur nominale (telle que le dispositif d'ancrage de l'insert ne sera ni trop ni insuffisamment recouvert par le béton), on place l'insert à une position qui est très proche de la position souhaitée. Il suffit d'une petite modification de l'enfoncement pour rattraper une éventuelle erreur de position de la surface du béton. La petitesse de cette modification autorise un ajustement très précis.
• L'insert conserve cette position avec cette précision pendant toute la durée de prise du béton parce que celui-ci retrouve rapidement, après l'arrêt des vibrations, une consistance ferme qui évite un déplacement du béton ou de l'insert sous l'action de leur poids.

The process thus characterized also provides great precision thanks to the collaboration of the three characteristics below:

• The fact of vibrating the concrete makes it possible to temporarily liquefy it in the vicinity of the point of application of the vibrations, thus allowing easy sinking, good coating of the drowned parts of the insert, and de facto good sealing. It should be noted that the vibrations can be applied via the insert or another device independent of the insert, and placed in the concrete, in the vicinity of the insert.
• The fact that the concrete is placed first, that it is smoothed, and rectified so that its surface has a relatively precise position has the effect that by driving the insert to a nominal depth (such as the device of anchoring of the insert will be neither too much nor insufficiently covered by concrete), the insert is placed in a position which is very close to the desired position. It only takes a small change in the penetration to make up for a possible error in the position of the concrete surface. The smallness of this modification allows a very precise adjustment.
• The insert maintains this position with this precision throughout the setting time of the concrete because it quickly regains, after the vibrations stop, a firm consistency which prevents displacement of the concrete or the insert under the action of their weight.

• mettre le béton sous la forme d'une dalle ayant une surface unie dont la position est déduite de la position prévue pour le plan de roulement de la voie ;
• puis, pendant que le béton est frais, enfoncer chaque selle dans la dalle de béton, en faisant vibrer le béton autour de cette selle, jusqu'à ce qu'elle atteigne une position donnée, avec une tolérance donnée.

When applied to the production of a railway track comprising rails supported by saddles provided with anchoring devices capable of being sealed in concrete, the method according to the invention is characterized in that it also consists of:

• putting the concrete in the form of a slab having a smooth surface, the position of which is deduced from the position provided for the running surface of the track;
• then, while the concrete is fresh, push each saddle into the concrete slab, vibrating the concrete around this saddle, until it reaches a given position, with a given tolerance.

The process thus characterized makes it possible to significantly reduce the cost of production of a railway track, since there is no longer any step of fixing spacers, and check its position before pouring concrete. The precision obtained on the position of each saddle is sufficient to obtain the desired precision for the spacing between the two rails of a track, and for the position of the running surface. In addition, the fact of laying a concrete slab before laying the rails, and not next, allows the use of a conventional sliding formwork machine which allows pour a concrete slab with very little labor.

According to a preferred embodiment, the method according to the invention is characterized in that, for driving a saddle into a concrete slab, vibrating this saddle, until it reaches a given position, with a given tolerance, it consists in slaving the position of the saddle to a predetermined position setpoint, along three axes orthogonal to each other, or another equivalent reference.

The process thus characterized makes it possible to automate the insertion of the saddle, while providing excellent position accuracy.

• dans une première étape, à enfoncer la selle avec une première vitesse fixée, en laissant une certaine liberté à la selle dans un plan horizontal, et en faisant vibrer cette selle avec une fréquence et une amplitude de vibration adaptées à un enfoncement rapide, jusqu'à ce qu'elle atteigne une position voisine de la consigne ;
• puis, dans une seconde étape, à positionner la selle avec une seconde vitesse fixée, inférieure à la première, en faisant vibrer cette selle avec une fréquence et une amplitude de vibration adaptées à un positionnement fin, jusqu'à ce qu'elle atteigne une position correspondant à la consigne.

According to a preferred embodiment, the method according to the invention is characterized in that, to push a saddle until it reaches a given position, with a given position, it consists:

• in a first step, to depress the saddle with a first fixed speed, leaving a certain freedom to the saddle in a horizontal plane, and by vibrating this saddle with a frequency and an amplitude of vibration adapted to rapid depressing, until that it reaches a position close to the setpoint;
• then, in a second step, to position the saddle with a second fixed speed, lower than the first, by vibrating this saddle with a frequency and amplitude of vibration adapted to fine positioning, until it reaches a position corresponding to the setpoint.

The invention also relates to a device for implementing the method according to the invention.

Finally, the subject of the invention is a railway track obtained by the process according to the invention.

• la figure 1 représente un exemple de selle pouvant être utilisé pour réaliser une voie de chemin de fer, sans traverses ;
• la figure 2 représente une vue en coupe d'une voie de chemin de fer comportant ce type de selle, et dont les selles ont été insérées en appliquant le procédé selon l'invention ;
• les figures 3 et 4 représentent respectivement une vue de dessus et une vue de côté, en coupe, de la partie principale d'un exemple de réalisation du dispositif selon l'invention ; cet exemple étant un dispositif d'insertion pour insérer une selle de ce type dans une dalle de béton ;
• la figure 5 représente une vue d'ensemble de cet exemple de réalisation ;
• les figures 6 à 9 illustrent quatre étapes successives du fonctionnement de cet exemple de réalisation ;
• les figures 10 , 11, et 12 représentent deux vues de face et une vue de dessus d'une machine mobile pouvant insérer simultanément deux selles pour réaliser une voie de chemin de fer.

The invention will be better understood and other details will appear with the aid of the description below of exemplary embodiments of the device for implementing the method according to the invention; and using the figures accompanying this description:

• Figure 1 shows an example of a saddle that can be used to make a railway track, without ties;
• 2 shows a sectional view of a railway track comprising this type of saddle, and whose saddles were inserted by applying the method according to the invention;
• Figures 3 and 4 show respectively a top view and a side view, in section, of the main part of an embodiment of the device according to the invention; this example being an insertion device for inserting a saddle of this type in a concrete slab;
• FIG. 5 represents an overall view of this exemplary embodiment;
• Figures 6 to 9 illustrate four successive steps in the operation of this embodiment;
• Figures 10, 11, and 12 show two front views and a top view of a mobile machine capable of simultaneously inserting two saddles to make a railway track.

• une plaque de tôle d'acier emboutie, 3 ;
• et deux goujons ayant chacun une tige filetée, respectivement référencée 2 et 4, permettant de fixer un rail sur la selle par des écrous, et une tige de scellement, référencée respectivement 9 et 6, ayant une forme généralement cylindrique prolongeant la tige filetée, et présentant des aspérités, circulaires par exemple, assurant la retenue dans le béton une fois que celui-ci a durci.

The method according to the invention can be used to insert any type of metallic, or non-metallic, insert that can be sealed in concrete. FIG. 1 shows an example of a saddle for a railway rail, which can be inserted by applying the method according to the invention. This example of saddle, referenced 1, includes:

• a stamped sheet steel plate, 3;
• and two studs each having a threaded rod, respectively referenced 2 and 4, making it possible to fix a rail on the saddle by nuts, and a sealing rod, referenced respectively 9 and 6, having a generally cylindrical shape extending the threaded rod, and with roughness, circular for example, ensuring the retention in the concrete once it has hardened.

The plate 3 has a generally rectangular, flat and horizontal shape, comprising : a vertical border 11 over its entire periphery, four reinforcing ribs, and two bosses 5 and 10 having slightly inclined vertical walls. These bosses 5 and 10 are provided in particular for collaborating with parts, not shown, which will be used for the subsequent fixing of a rail. In the use which is made here, bosses 5 and 10 also have the function of providing free space allowing the rise of a volume of concrete equal to the volume of concrete displaced by the sealing rods 6 and 9 when the saddle is driven into the concrete. On the other hand, saddles 1 and 1 ′ have a plurality of orifices 7, 12 allowing the air to escape when the concrete fills the bowl formed by the plate 3, its edge 11, and the bosses 5 and 10.

Each stud is fixed to the sole by force fitting, or by welding. The threaded part of the stud can be protected during all insertion operations of the saddle, by means of a plastic sleeve screwed on this threaded part.

The method according to the invention is applicable not only to this type of insert but also to any other type of insert that can be sealed in concrete.

Figure 2 shows in section an example of a railway track made using this type of saddle and applying the method according to the invention. This figure 2 shows two rails, 12 and 14, fixed respectively on two saddles 13 and 15, by nuts and parts conventionally interposed between each nut and the rail.

These two saddles 13 and 15 are sealed in a concrete slab 16 whose surface is flat, each of the two saddles 13 and 15 being pressed into the surface of the slab 16 to a depth such that the plane of these saddles is approximately in the plan of the surface of the slab 16. The concrete fills each saddle and thus ensures anchoring stronger than if it were only secured by the anchor rods.

The altitude of each of the rails 12 and 14 is determined on the one hand by the altitude of the surface of the slab 16 which is manufactured with a given precision, of the order of a few millimeters, and on the other hand is a function of the sinking of the saddle in the concrete of slab 16, this recess being adjusted so that the running surface has a given position, with an accuracy of the order of a millimeter. The spacing between the rails 12 and 14 is determined by the distance between the two saddles when they are sealed. he there are no gauge spacers between these rails, nor a priori adjustment shim.

Figures 3 and 4 respectively represent a top view and a view in section of the main part of an example of a specially adapted insertion device when inserting the type of saddle shown in Figure 1. This example includes a base made of a sheet 30 intended to be placed directly on the surface 25 a concrete slab 31 into which a saddle must be inserted. This concrete is fresh, smooth, and has a firm consistency. This sheet 30 has a circular opening on which is welded a vertical tube 21 allowing the passage of a movable part.

• un réceptacle 28 en polyuréthane, ayant une surface interne épousant la forme d'une selle et comportant un joint interne souple 29, le réceptacle 28 s'appuyant sur toute la périphérie de la selle 1 par l'intermédiaire de ce joint 29 ; et ce réceptacle 28 ayant une forme externe circulaire de diamètre légèrement inférieur à celui du tube 21 de façon à pouvoir passer dans le tube 21, tout en empêchant une remontée du béton dans le tube 21 pour confiner le béton ;
• une plaque support 22 en polyuréthane, ayant une forme circulaire de diamètre légèrement inférieur au diamètre du tube 21, et qui supporte notamment le réceptacle 28 placé sous cette plaque 22;
• quatre blocs élastiques en caoutchouc 24a, 24b, 24c, 24d, fixés sur la plaque 22 ;
• deux bras verticaux 40a et 40b, fixés sur la plaque 22 ;
• un dispositif de vibration 35, qui est fixé sur une plaque d'acier 32, cette dernière étant fixée au sommet des quatre blocs élastiques 24a, 24b, 24c, 24d ;
• deux pinces 23a et 23b, à commande hydraulique, fixées à la plaque 32, et serrant respectivement les tiges filetées des deux goujons de la selle 1 (la figure 4 ne représentant que la pince 23a serrant la tige filetée 2) ;
• huit doigts de positionnement 26a à 26h, dont les extrémités appuient sur la surface horizontale de la selle 1 en restant en contact avec les parois quasi-verticales des bossages 5 et 10 pour donner à la selle 1 une position bien déterminée dans le plan horizontal, chacun de ces doigts coulissant dans un fourreau, 27a à 27h respectivement, fixé à la plaque 22 ; quatre doigts 26a à 26d étant solidaires d'une pièce 33a (représentée partiellement sur la figure4), et quatre doigts 26e à 26h étant étant solidaires d'une pièce homologue 33b non représentée mais solidaire de la pièce 33a par l'intermédiaire d'un étrier 39 qui est vu de côté sur la figure 4.

This mobile part includes:

• a receptacle 28 made of polyurethane, having an internal surface conforming to the shape of a saddle and comprising a flexible internal seal 29, the receptacle 28 resting on the entire periphery of the saddle 1 by means of this seal 29; and this receptacle 28 having a circular external shape of diameter slightly smaller than that of the tube 21 so as to be able to pass through the tube 21, while preventing a rise of the concrete in the tube 21 to confine the concrete;
• a polyurethane support plate 22, having a circular shape with a diameter slightly smaller than the diameter of the tube 21, and which in particular supports the receptacle 28 placed under this plate 22;
• four elastic rubber blocks 24a, 24b, 24c, 24d, fixed to the plate 22;
• two vertical arms 40a and 40b, fixed on the plate 22;
• a vibration device 35, which is fixed to a steel plate 32, the latter being fixed to the top of the four elastic blocks 24a, 24b, 24c, 24d;
• two clamps 23a and 23b, hydraulically controlled, fixed to the plate 32, and respectively tightening the threaded rods of the two studs of the saddle 1 (FIG. 4 showing only the clamp 23a tightening the threaded rod 2);
• eight positioning fingers 26a to 26h, the ends of which press on the horizontal surface of the saddle 1 while remaining in contact with the quasi-vertical walls of the bosses 5 and 10 to give the saddle 1 a well-determined position in the horizontal plane, each of these fingers sliding in a sheath, 27a to 27h respectively, fixed to the plate 22; four fingers 26a to 26d being secured to a part 33a (shown partially in FIG. 4), and four fingers 26e to 26h being being secured to a homologous piece 33b not shown but secured to the piece 33a by means of a caliper 39 which is seen from the side in FIG. 4.

For clarity, Figure 3 does not show the vibration device 35, nor parts 33a and 33b, nor the caliper 39. Figure 4 does not represent the hydraulic hoses feeding the clamps and the vibration device.

The vibration device 35 includes one or more vibrators, each vibrator being constituted for example by a hydraulic motor having an unbalance. The whole vibrating device 35 vibrates while driving in its movement the plate 32 which has a certain freedom thanks to the elastic blocks 24a to 24d. The clamps 23a and 23b transmit vibrations to anchor rods 9 and 6. Under the action of these vibrations, concrete is much more fluid in the vicinity of the anchor rods, which allows them to be pushed in with less force and get a much more precise positioning.

• une poutre horizontale 45 et deux guides cylindriques verticaux 43a et 43b, constituant un portique ;
• une pièce coulissante 42 coulissant verticalement en étant guidée par les deux guides 43a et 43b ;
• un premier vérin hydraulique 44 ayant une extrémité fixée à la poutre 45 et l'autre extrémité fixée à la pièce coulissante 42 ;
• les deux bras verticaux 40a et 40b reliant la pièce coulissante 42 à la plaque support 22 ;
• un second vérin hydraulique 41 ayant une extrémité fixée à la pièce coulissante 42 et ayant son autre extrémité fixée à l'étrier 39 qui enjambe le dispositif de vibration 35 ;
• et une unité de commande UC reliée :
  • à un capteur de position 46 fixé d'une part à la poutre 45 et d'autre part à la pièce coulissante 42 pour déterminer l'altitude de la selle 1 par rapport à la plaque 30 qui repose sur la surface 25 de la dalle de béton 31 ;
  • à un capteur de position CP solidaire de la poutre 45, pour déterminer l'altitude de la plaque 30 par rapport à un plan de référence appelé plan laser parce qu'il est repéré par un faisceau laser tournant dans un plan donné ;
  • au vérin 44 par deux tuyaux pour l'actionner ;
  • au vérin 41 par deux tuyaux pour l'actionner ;
  • et au dispositif de vibration 35 par deux tuyaux pour l'actionner.

FIG. 5 represents the assembly of this exemplary embodiment, also representing means making it possible to move the support plate 22 vertically, and to vertically move the stirrup 39. These means comprise:

• a horizontal beam 45 and two vertical cylindrical guides 43a and 43b, constituting a gantry;
• a sliding part 42 sliding vertically while being guided by the two guides 43a and 43b;
• a first hydraulic cylinder 44 having one end fixed to the beam 45 and the other end fixed to the sliding part 42;
• the two vertical arms 40a and 40b connecting the sliding part 42 to the support plate 22;
• a second hydraulic cylinder 41 having one end fixed to the sliding piece 42 and having its other end fixed to the stirrup 39 which spans the vibration device 35;
• and a control unit UC connected:
  • to a position sensor 46 fixed on the one hand to the beam 45 and on the other hand to the sliding piece 42 to determine the altitude of the saddle 1 relative to the plate 30 which rests on the surface 25 of the slab of concrete 31;
  • to a position sensor CP secured to the beam 45, to determine the altitude of the plate 30 relative to a reference plane called the laser plane because it is identified by a laser beam rotating in a given plane;
  • to the jack 44 by two pipes to actuate it;
  • to the jack 41 by two pipes to actuate it;
  • and to the vibration device 35 by two pipes to activate it.

The control unit UC controls several successive stages. Figure 6 illustrates a first step during which the saddle 1 is put in place manually or automatically, inside the receptacle 28, by inserting the threaded rods studs in the hydraulic clamps 23a and 23b (The latter is not shown). The cylinders 44 and 41 are retracted, which leaves space between the tube 21 and the receptacle 28 for accessing the interior of the latter.

Figure 7 illustrates a second step during which the saddle 1 is depressed quickly. During this whole step, the vibration device 35 is activated with amplitude and frequency adapted to facilitate penetration of the saddle 1 in the concrete slab 31, making the concrete more fluid in the vicinity of the anchor rods. The rubber blocks 24a, etc ... allow the plate 32 to move slightly in all directions, relative to the plate 22. The jack 44 is actuated to push the saddle 1 to a position close to the final position expected, to within a few millimeters. The jack 44 moves: the sliding part 42, the arms 40a and 40b (not shown), the support plate 22, and the receptacle 28 which are there associates. The saddle 1 is therefore pushed into the liquefied concrete by vibrations. The receptacle 28 is lowered until it is in the vicinity of the surface 25 of the concrete slab. he note that the guide fingers 26a, etc., are still in the raised position and are not in contact with the saddle 1.

Figure 8 illustrates a third step of inserting the saddle 1, consisting of complete the insertion at a lower speed, suitable for precise positioning, up to the final depth planned for the saddle. The jack 44 is activated again, but with a lower speed. The vibration device 35 is activated, but the amplitude and the frequency of the vibrations are adapted for precise positioning of the saddle 1. The receptacle 28 and the plate 30, which are almost contiguous, confine the concrete and force it to go up in bosses 5 and 10. When saddle 1 has reached the position provided, the vibration device 35 and the jack 44 are stopped.

FIG. 9 illustrates a fourth step during which the vibration device 35 is arrested. The cylinder 41 is activated in turn. It lowers the stirrup 39 which is integral of part 33a (partially shown) and of part 33b (not shown), these parts 33a and 33b supporting the fingers 26a, etc. The stirrup 39 lowers until it stops on the plate 32. The ends of the fingers 26a, etc., then come into contact with the part plane of the saddle 1. If the saddle 1 is not perfectly positioned in the horizontal plane, the fingers rub on the vertical walls of the bosses 5 and 10 of the saddle 1 and cause a slight movement of the saddle 1, in the horizontal plane, to reposition the saddle 1 in a position well defined by the eight fingers. The vibrations having stopped, the concrete gradually regains its firm consistency. The clamps 23a, etc ... are maintained tight, and the fingers 26a, etc. are held in this position until that the increase in the viscosity of the concrete is sufficient to prevent any displacement of the saddle when raising the fingers.

The hydraulic clamps 23a and 23b are then controlled to release the saddle studs 1. Then the cylinder 41 is activated in the opposite direction to raise the fingers 26a, etc ... Then the jack 44 is activated in the opposite direction to reassemble the entire moving part of the insertion device.

Figures 10 and 11 respectively represent two front views of a machine mobile allowing the insertion of two saddles simultaneously. In Figure 10, the machine is in a state allowing to move it and to prepare the insertion of a saddle. In Figure 11, the machine is inserting a saddle into a fresh concrete slab 62. Figure 12 shows a top view. In these figures, the machine has already inserted stool 70 to 76 in a concrete slab 62.

This exemplary embodiment includes a mobile platform 52 supporting two insertion devices 51a and 51b, identical to each other and which can be analogous the insertion device shown in Figures 3 to 5, and which has been described above. They notably include position sensors 64a, respectively 64b, analogous to the CP sensor; and control units UC1, respectively UC2, analogous to the UC control unit. The devices 51a and 51b are mounted on a carriage 63 which is integral with the platform 52 and movable relative to the latter according to two horizontal axes, orthogonal to each other. On the other hand, a set of cylinders, not shown, lowers the devices 51a and 51b until their bases (sheet 30) rest on the surface of the concrete slab 62. The devices 51a and 51b cross the carriage 63 through openings 61a and 61b respectively, and pass through it the platform 52 through an opening 62.

The platform 52 is mounted on four tracks 53a, 53b, 53c, 53d, via four horizontal articulated arms 55a, 55b, 55c, 55d, for adjusting the spacing between the tracks, and by means of four vertical legs 57a, 57b, 57c, 57d, allowing the height of each arm to be adjusted independently 55a, 55b, 55c, 55d, respectively with respect to the tracks 53a, 53b, 53c, 53d, resting On the ground.

The position of the platform 52 is controlled according to three orthogonal axes, at the means of a UC3 control unit, so that it follows the profile provided for the raceway, therefore it follows the surface of the slab 62. The legs 54a and 54b respectively support sensors 58a and 58b which follow a parallel guide 57 to the longitudinal profile of the rails to be installed. This guide 57 carries markers, in order to enslave the position of the platform 52 along two horizontal axes with reference to this guide 57. The platform 52 spans the concrete slab 62 and moves along this slab 62 by means of motors operating the tracks 53a, ..., 53d.

On the other hand, the legs 54a and 54b respectively carry sensors 60a and 60b making it possible to determine the respective altitudes of the arms 55a and 55b relative to a laser plane, taking into account the height adjustment of these arms relative to the legs 54a and 54b. Knowing these altitudes allows these altitudes to be controlled by predetermined set values so that the platform 52 follows the profile of the track.

The concrete used has a firm consistency. Slab 62 has been freshly poured, vibrated in place, rectified, and smoothed, by a conventional sliding formwork machine, such as those used to make concrete pavements, for motorways. She gives to the surface of the slab a position deducted from the position provided for the running surface of the track, with an accuracy of the order of 2 millimeters, thanks to servo-control of classic positions.

The saddle inserts, 51a and 51b, are moved apart by a corresponding interval at the scheduled rail interval. The movable carriage 63 moves them together and allows to refine the insertion position, with a precision of the order of a millimeter along two horizontal axes, even better than that provided by the platform 52.

The mobile carriage 63 carries a position sensor 59 which makes it possible to control the position of the carriage 63 along two horizontal axes, with reference to the position of the same guide 57, but with a finer tolerance than the tolerance on the position of the platform 52. The carriage is moved by two motors, not shown, controlled by a UC4 control unit, as a function of the measurements made by the sensor 59 and in depending on the position provided for the two saddles to be inserted.

The slaving of the insertion devices 51a and 51b along a vertical axis, by the UC1 and UC2 control units, allows each saddle to be inserted with precision an altitude of the order of a millimeter, even better than the precision obtained on the altitude of the surface of the concrete layer 62.

Position control devices, referring to the position of a guide and at the position of a laser plane, are conventional devices. But other known types position control device could also be used to obtain a precise position of each saddle.

According to an alternative embodiment, the insertion devices 51a and 51b could be mounted directly on the machine used to pour the slab in place concrete 62, instead of the platform 52. The production of this machine will not be described because it is analogous to the realization of a machine conventionally used for make concrete highways.

Claims (9)

1. A method of accurately placing an insert in concrete, said insert including one or more cavities (5, 10) to be filled by the concrete, which method consists of:

   preparing a concrete (31) having a firm consistency;

   placing the concrete, and levelling and smoothing its surface (36) while it is fresh, to impart to its surface a given position with a given tolerance;

   then, while the concrete is fresh, moving the insert (1) into the concrete, causing the concrete around the insert to vibrate during its movement, until it reaches a given position, with a given tolerance;

      characterized in that it further consists in confining the concrete (31) by means (28, 30) for preventing the concrete rising up around the insert during the placing of the insert in the concrete, in order to force the concrete to fill each cavity of the insert.
2. A method according to claim 1, applied to the production of a rail track including rails (12, 14) supported by sole plates (13, 15) provided with anchor devices adapted to be embedded in concrete, characterized in that it further consists in:

   forming the concrete into a slab (16) having a unified surface whose position is deduced from the intended position of the rolling plane of the track;

   then, while the concrete is fresh, driving each sole plate (13, 15) into the concrete slab, causing the concrete to vibrate around said sole plate, until it reaches a given position, with a given tolerance.
3. A method according to claim 2, characterized in that, for driving in each sole plate (13, 15) until it reaches a given position, it consists in slaving the position of said sole plate to a position set point along three mutually orthogonal axes or an equivalent frame of reference.
4. A method according to claim 3, characterized in that, to drive in each sole plate until it reaches a given position, with a given accuracy, it consists of:

   in a first stage driving in the sole plate with a first speed, allowing the sole plate some liberty in a horizontal plane, and causing the sole plate to vibrate with a frequency and amplitude of vibration suitable for rapidly driving it in, until it reaches a position close to the set point;

   then, in a second stage, positioning the sole plate at a second speed, lower than the first, causing the sole plate to vibrate with a frequency and an amplitude of vibration suited to fine positioning, until it reaches a position corresponding to the set point.
5. A device for placing an insert accurately in concrete, said insert (1) including one or more cavities (5, 10) to be filled with concrete, the device including:

   means (40, 42, 44) for moving an insert (1) into fresh concrete having a firm consistency;

   means (35) for causing the concrete to vibrate around the insert during the movement of the insert; and

   means (46, UC) for determining the position of the insert and for controlling the means for moving the insert, so as to stop the movement of the insert when it has reached a given position, with a given tolerance;

      characterized in that it further includes means (28, 30) for confining the concrete (31) and preventing the concrete rising up around the insert during the placing of the insert in the concrete, in order to force the concrete to fill each cavity of the insert.
6. A device according to claim 5, for accurately placing in a concrete slab (62) at least one sole plate (70 to 76) intended to support a rail, characterized in that the means (58a, 58b, 59, 60a, 60b, UC1, UC2, UC3, UC4) for determining the position and for controlling the driving in means determine the position of each sole plate along three axes, or some other equivalent frame of reference, relative to the intended position of said sole plate.
7. A device according to claim 6, characterized in that the means for determining the position and for controlling the driving in means include:

   means (CP, UC, 46) for controlling the position of the sole plate along an axis parallel to the direction of driving in the sole plate;

   and means for controlling the position of the sole plate along two other axes, including:

   a mobile platform (52) which straddles the concrete slab (62);

   a carriage (63) which is carried by the mobile platform (52) and which is mobile relative to the mobile platform (52) along two axes perpendicular to the driving in direction;

   first control means (53 to 55, UC3) for controlling the position of the platform (52) relative to a reference (57) at least along two horizontal axes;

   and second control means (59, UC4) for controlling the position of the carriage (63) relative to a reference (57) along two horizontal axes.
8. A device according to any of claims 5 to 7, characterized in that it further includes means for pouring a concrete slab.
9. A rail track obtained by inserting sole plates (13, 15) into a concrete slab (16) using a method according to any of claims 2 to 4.

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