ES2546434T3 - Railway sleeper - Google Patents

Abstract

Railway crossbeam, which has a concrete body (2) with a crossbar base (3) fixed thereto, being provided for the shear force resistant connection of the crossbar base (3) with the concrete body (2) ) a connecting layer (6), which is connected on one side with the crossbar base (3) and on the other hand with the concrete body (2) and in this sense is partially embedded in the concrete of the concrete body ( 2), characterized in that the joining layer (6) is formed by a separation fabric, comprising first and second layers (9, 10), which are kept separated from each other by means of joining threads (11) and of which The first layer (9) is embedded in the concrete of the concrete body (2).

Description

Railway sleeper

The invention relates to a railway sleeper, which has a concrete body with a sleeper base fixed thereto, and a connecting layer is provided for the resistance to the shear force of the sleeper base with the concrete body. which is connected on one side with the base of the sleeper and on the other hand with the concrete body and in this sense is partially embedded in the concrete of the concrete body.

Cross ties made of elastic plastic, for example foamed polyurethane, for railway sleepers are used in particular for protection against vibrations and protection of the gravel bed in concrete sleepers. On such crosspieces, not only vertical but also horizontal forces act, in particular in the transverse direction to the rails, such horizontal forces being produced, for example, when passing a train through a curved route or by temperature expansion. In order to maintain a sufficient resistance to transverse displacement, the transverse forces that are produced must be absorbed. Therefore, to achieve a shear-resistant joint of the concrete body of the railway sleeper with the gravel bed, with intermediation of the sleeper base that is located on the gravel bed, there must be a bond resistant to the shear force between the concrete body and the crossbar base.

In order to configure a shear-resistant joint between the concrete body of the railway crossbar and the crossbar base, it is known to form the crossbar base with elevations and recess surfaces. Such a configuration follows, for example, from FR 2 753 998 A1. From DE 43 15 215 A and EP 609 729 A, railway sleepers are known, in which layers of geotextile material are fixed on the bottom side of the crossbeam facing the concrete body, to protect the base of Naughty against the penetration of gravel tips.

For firm tracks, sleepers are partially surrounded by elastic profiles (the so-called cross sleepers). Such sleepers are not found on a bed of gravel and the existing requirements in the case of firm roads and the problems that appear differ from those of tracks with sleepers installed on a bed of gravel.

A railway sleeper of the type mentioned at the beginning follows from EP 1 298 252 A2. The sleeper base is connected to the concrete body of the railway sleeper through a tie layer, which is formed by a randomly oriented fiber layer, in particular a nonwoven fabric layer. In this sense, the fibers of the randomly oriented fiber layer are on the one hand embedded in the concrete of the concrete body in its lower side area close to the surface and on the other hand embedded in the material of the naughty or welded base material with the same.

From the previous use, a railway sleeper is also known in which a three-dimensional, thermally hardened random entanglement with a relatively large thickness of the fibers is used as the tie layer between the base of the crossbar and the concrete body (= "threads of plastic ”) of the random entanglement, this random entanglement being embedded in turn on the one hand in the concrete body and on the other hand in the material of the naughty base.

From EP 1 445 378 A2 and from WO 2009/108972 A1, concrete sleepers for railway tracks are also detached, which has a sleeper base on its lower side. To establish an improved interconnection between the concrete body of the sleeper and the base of the sleeper, a fiber layer is disposed, which is integrated in both the concrete and the plastic layer of the base.

By means of the three-dimensional structure partially embedded in the concrete of these previously known bonding layers, durable bonding is improved, they resist the tearing and shearing force between the concrete body of the railway crossbar and the crossbar base. However, previously known tie layers, formed by randomly oriented fiber layers, in particular random entanglements or punched nonwoven layers, have disadvantages in different aspects. Thus, the three-dimensional shape of nonwoven fabrics is limited, which leads to problems in particular when a pronounced layer of cement slurry (= cement paste) is present in the boundary layer of the concrete body, which is formed by cement , water and fine particles. A layer of this type can only transmit relatively small forces, so that as an additional consequence the forces between the joint layer and the concrete body are also limited. With respect to this, a three-dimensional random entanglement has the advantage that it can also be embedded in deeper areas of the concrete body, whereby in principle the transmission of forces can be increased. However, in this sense it is disadvantageous that such random entanglements are relatively heterogeneous, with holes, clusters of fibers like lumps, variations with respect to thickness, etc. appearing normally. Therefore, the transmission of forces achieved through the bonding layer is subject to a certain margin of error.

The object of the invention is to provide an improved concrete crossbeam with respect to this. According to

invention, this is achieved by a railway sleeper with the features of claim 1.

In a railway sleeper according to the invention, the sleeper base is connected to the concrete body through a connecting layer, which is formed by a separation fabric. This comprises two woven layers (these are also called product surfaces), which are kept separated from each other by joining threads. The first of these layers is embedded in this direction in the concrete of the concrete body.

In an advantageous embodiment of the invention, the second layer is embedded in the crossbeam base material. In another possible embodiment of the invention, the second layer is not embedded in the crossbeam base material, if not bonded by adhesion with the outer surface of the crossbeam base. An adhesion bond of this type can be formed, for example, by pressing the second layer against the surface of the reaction mixture, which after hardening forms the base of the crossbar. With the hardening of the reaction mixture, adhesion bonding then occurs. Another possibility is that the second layer is glued or thermally welded to the base of the sleeper after hardening.

The two woven layers may have drawings that differ from each other and / or be formed by differently configured threads. In this way, the union of the first layer with the concrete body and the union of the second layer with the crossbar base can be optimized.

The term thread is used herein in general for monofilament threads, spun yarns and twisted threads. Spun yarns are virtually endless filiform products, which may be composed of finite fibers (= yarn)

or by several elementary threads practically endless. In the case of twisted threads these are special forms of spun threads with two or more twisted individual spun threads.

Further advantages and details of the invention will be explained below by means of the accompanying drawings. In these

show:

figure 1

a schematic representation of a railway sleeper according to the invention;

figure 2

a schematic three-dimensional representation of a section of a tie layer according to a

embodiment of the invention;

figure 3

a side view of the tie layer of figure 2, visual sense A.

Figure 1 shows a schematic representation of a railway sleeper 1 in the form of a concrete sleeper, comprising a concrete body 2 and a sleeper base 3 fixed on its lower side. With the sleeper base 3, the railway sleeper 1 is located on a bed of gravel 4 indicated in Figure 1.

The railway sleepers 1 installed in the gravel bed separated from each other support a track, of which in figure 1 a rail 5 is indicated with broken lines. In this sense, the fastening of the rail 5 to the railway sleeper 1 is not shown. A layer of an elastic material can be arranged between the rail 5 and the railway sleeper 1.

The concrete body 2 is formed by reinforced concrete. In this sense it can be a "late formwork concrete", in which the formwork takes place when the concrete has hardened, or an "early formwork concrete", which can already be removed before the concrete hardens. For example, the concrete body 2 may be configured as prestressed concrete.

The sleeper base 3 is composed of an elastic plastic. A configuration from foamed polyurethane is preferred. They are conceivable and possible configurations from other elastomers or thermoplastic elastomers, in particular foamed.

The crossbar base 3 preferably covers only the lower side of the concrete body 2.

The connection of the crossbeam base 3 with the concrete body 2 takes place through a joint layer 6. The joint layer 6 is embedded in this direction in the concrete of the concrete body 2 through a part of its thickness d. Through another part of its thickness d, the joining layer 6 is embedded in the material of the cross-member base 3.

In Figure 1 it is indicated that the encrustations of the joint layer 6 in the concrete body 2 and in the crossbar base 3 total the total thickness d of the joint layer 6. Therefore, in an area, which It is located within the extension of the joining layer 6, there is a boundary surface between the concrete of the concrete body 2 and the material of the crossbar base 3.

Instead, it would also be possible that between the concrete body 2 and the crossbeam base 3 remained a layer of the bonding layer 6, which is not embedded either in the concrete body 2 or in the crossbar base 3. This it would then be found between the material of the concrete body 2 and the material of the crossbar base 3, and the material

of the concrete body 2 and the material of the crossbar base 3 would not directly limit one another (they do not form a mutual boundary surface).

Embedding of the bonding layer 6 in the concrete body 2 takes place during the manufacture of the concrete body 2, before the concrete of the concrete body 2 has hardened. During the hardening of the concrete, the dragging union takes place of force with the concrete body 2. In this sense, unions with form drag between the connecting layer 6 and the concrete body 2 are produced with respect to the transverse direction 7 of the railway sleeper 1. In addition, the joining layer 6 has recess surfaces, behind which the concrete of the concrete body 2 penetrates during the embedding of the joint layer 6 in the concrete body 2, whereby trailing joints are formed in the direction of tearing ( = extraction direction) 8 which is at a right angle to the lower side of the concrete body 2 or at a right angle to the transverse direction 7.

When after casting the concrete body 2, before it has hardened, the bonding layer 6 is embedded in the concrete body 2, it is already preferably joined with the crossbar base 3. The crossbar base 3 with the layer of connection 6 fixed thereto, which points towards the concrete of the concrete body 2, is placed in the casting mold on the cast concrete body 2 and is preferably introduced by vibration into the concrete of the concrete body 2. Instead of this, the crossbeam base 3 with the connecting layer 6 directed towards the mold cavity could also have already been introduced before casting the crossbeam into the mold cavity or applied to it, so that the mold cavity is delimit the base of the sleeper with the connection layer 6 fixed to it, after which the concrete is cast.

The embedding of the joint layer 6 in the material of the cross-member base 3 takes place before the plastic of the cross-section base 3 has hardened. To this end, the connection layer 6 is correspondingly pressed both into the reaction mixture, which after hardening forms the base of sleeper 3.

Instead of embedding the bonding layer 6 in the material of the crossbar base 3, the bonding layer 6 could also be attached to the surface of the crossbar base 3 by adhesion, for example by bonding and / or welding thermal An adhesion bond of this type can take place after the material of the crossbar base 3 has already hardened. An adhesion joint can also be achieved by fixing the bonding layer 6 before hardening of the crossbar base material. 3 to its surface, so that during the hardening of the material of the crossbeam base 3 the bonding is achieved by adhesion. In case of adhesion bonding with the surface of the crossbar base 3, if desired, the bonding layer 6 can be embedded with full thickness in the material of the concrete body 2, so that, regardless of its sections of surface on which it is joined by adhesion with the crossbar base 3, is completely embedded in the material of the concrete body 2, that is, except for these surfaces, it is completely surrounded by the material of the concrete body 2.

It would also be basically conceivable and possible, although less preferred, to integrate the bonding layer 6 firstly into the material of the concrete body 2 and only then to form the joint with the crossbar base 3.

The interconnection between the concrete body 2 and the crossbar base 3 takes place advantageously already in the factory, so that no work on site is necessary in this regard.

The configuration of the tie layer 6 is schematically represented in Figures 2 and 3. The tie layer 6 is formed by a separation fabric. This comprises first and second woven layers 9, 10, which are kept separated from each other by connecting threads 11.

The first and second layers 9, 10 are also referred to in such separation fabrics as product surfaces.

In an advantageous embodiment of the invention, the connecting threads 11 and the threads, from which the first and second layers 9, 10 are woven, are in each case independent threads, that is to say different. The connecting threads 11 are then called hair threads.

The drawings of the first and second woven layers are schematically indicated in Figures 2 and 3 by hexagons. This indicates holes that the first and second layers 9, 10 can present.

Different drawings of the first layer 9 or second layer 10 are possible, but advantageously at least the first layer 9 embedded in the concrete of the concrete body 2 has holes, preferably with internal widths of at least 3 mm, to facilitate embedding in the concrete concrete body 2.

When the second layer 10 is embedded in the material of the crossbeam base 3, then this also advantageously has holes, preferably with internal widths of at least 3 mm, to facilitate embedding in the material of the crossbeam base 3. When the Second layer 10 is attached to the outer surface of the cross-member base 3, the second layer 10 can also be relatively narrowly woven, without pronounced holes.

The first layer 9 is in a first plane 12 and the second layer 10 is in a second plane 13, both planes 12, 13 being parallel to each other and separated from each other.

The drawings of the first layer 9 and the second layer 10 may differ, to adapt the layers to the respective requirements. The threads, of which the first layer 9 and the second layer 10 are composed, can be the same or be configured differently to adapt to the respective requirements.

The number and arrangement of the connecting wires 11 can also be adapted to the specific requirements.

A possible embodiment of the connecting threads 11 provides that these are composed of a monofilament thread. However, a configuration from a spun yarn is also conceivable and possible.

The threads of the first layer 9 or second layer 10 may be formed by monofilament threads and / or spun threads, for example also in the form of twisted threads.

The connecting threads 11 and / or the threads of the first layer and / or the threads of the second layer may be composed, for example, of polyamide, polypropylene, PVC, polyethylene or combinations thereof, where appropriate also in relation With additional materials.

The production of a separation fabric usually takes place in a single production stage. For the first warp-woven layer or for the second warp-woven layer, for example, the body, knitting or fabric construction can be used.

The thickness of the separation fabric is defined by the separation of the two needle bars from each other. The thickness d of the separation fabric is favorably in the range of from 1.5 mm to 40 mm, with a thickness in the range of 2 mm to 20 mm being preferred.

By joining (= gluing in layers) the bonding layer 6 with the reaction mixture of the crossbar base 3, the second layer 10 directed towards the reaction mixture is pressed into the reaction mixture. A part of the connecting threads 11 as well as the first layer 9 protrude in this direction in any case still from the reaction mixture. The introduction of pressure into the reaction mixture preferably takes place at a predetermined depth, there being still under the second layer introduced under pressure 10 a reaction mixture layer. However, it is also conceivable and possible to press the second layer 10 under pressure throughout the depth of the reaction mixture therein. On the other hand, it can also be provided to press the second layer 10 only against the reaction mixture of the crossbeam base 3, after which during the hardening of the reaction mixture of the crossbeam base 3 a bond of material occurs.

In a further possible embodiment, the second layer 10 can be glued after hardening of the reaction mixture to the crossbar base 3.

As already mentioned, the embedding of the first layer 9 in the concrete of the concrete body 2 takes place favorably after the second layer 10 has already joined with the cross-member base 3.

The connecting threads 11 can run at different angles with respect to the first and second layers 9, 10. In order to guarantee a good resistance to the displacement of the first and second layers 9, 10 from one another and avoid an inclination of the structure under load by compression, for example in the case of separation fabrics it is known to arrange the connecting threads 11 in a cross manner between the first and second layers, preferably with crossing angles of approximately 45 °. For example, such a configuration can be used.

Separation fabrics are also known, in which the threads that are used for the configuration of the first and / or second layer 9, 10 are also used for the configuration of the connecting threads 11. Therefore there is no thread of separate hair. A configuration of this type of separation tissue can also be used.

The thickness of the crossbeam base 3 is preferably in the range of from 4 mm to 20 mm.

Legend of reference numbers:

1 railway sleeper 2 concrete body 3 sleeper base 4 gravel bed 5 rail 6 junction layer 7 cross direction

8

sense of tearing

9

first layer

10

Second layer

eleven

binding thread

5

12 foreground

13

background

Claims (6)

1. Railway crossbeam, which has a concrete body (2) with a crossbar base (3) fixed thereto, being provided for the shear force resistant connection of the crossbar base (3) with the body 5 of concrete (2) a connecting layer (6), which is joined on one side with the crossbar base (3) and on the other hand with the concrete body (2) and in this sense is partially embedded in the concrete of the body of concrete (2), characterized in that the joining layer (6) is formed by a separation fabric, which comprises first and second layers (9, 10), which are kept separated from each other by connecting threads (11) and of which the first layer (9) is embedded in the concrete of the body of 10 concrete (2). 2. Railroad crossbar according to claim 1, characterized in that the second layer (10) is embedded in the material of the crossbar base (3). 3. Railroad crossbar according to claim 1, characterized in that the second layer (10) is bonded by adhesion with the outer surface of the crossbar base (3). 4. Railway crossbar according to one of claims 1 to 3, characterized in that the thickness of the fabric of separation is in the range from 1.5 mm to 40 mm. twenty

5.

Railway crossbar according to claim 4, characterized in that the thickness of the separation fabric is in the range of from 2 mm to 20 mm.

6.

Railway crossbeam according to one of claims 1 to 5, characterized in that the connecting wires (11)

25 are formed by hair threads, which are present in addition to the threads from which the first and second layers are woven (9, 10). 7. Railway crossbar according to one of claims 1 to 6, characterized in that the connecting wires (11) are formed by monofilament wires.  DRAWINGS