ES2341300T3 - RAILWAY RAIL. - Google Patents

Abstract

The sleeper (8) has a rigid concrete block (9) with a lower surface, and an upper face to receive a longitudinal rail (4), where the block has a weight ranging between 400 and 450 kilograms. A shoe (20) receives the rigid block, and is formed of a rigid shell comprising a peripheral edge (50) bordering a base of the shell. A resilient tie plate (22) is arranged between the lower surface of the block and the base of the shoe. The tie plate has a dynamic stiffness ranging from 6-8 kilo-newtons per millimeter.

Description

Railway sleeper.

The present invention relates to a sleeper Rail, of the type comprising:

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a rigid block that has a lower face, and an upper face intended to receive at least one longitudinal rail,

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a shoe destined to receive the rigid block and constituted by a rigid hull provided with a bottom and a peripheral flange that borders this background,

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a resilient plate arranged between the underside of the rigid block and the bottom of the shoe.

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This type of sleepers are used frequently to place a railroad without ballast, for example in or on a construction such as a tunnel or a viaduct, which offers a solera or a slab.

EP-A-0 919 666 describes a naughty of this kind. The rigid shoe is recessed in a cement slab, with which it forms a rigid assembly.

Each rail usually rests on a resilient support element, arranged between each rail and the block rigid. The resilient support elements thus form a first elastic level They can be mounted at the time of placement of the track, or previously, for example at the time of assembly of the naughty.

The resilient plate arranged between the block and the rigid shoe itself constitutes a second level elastic.

The vibrations generated by the rails as they pass of trains are essentially buffered to the level of first and second elastic levels.

However, vibration attenuation mechanics to the passage of the train of this track system as You know currently, it is not entirely satisfactory. Effectively, cutoff frequency and insertion gain are higher that, for example, those of a slab track system floating.

The invention aims to improve the performance of attenuation of the vibrations of the sleeper above, especially in a frequency range of up to 250 Hz, which is considered to cause damage to buildings close, while limiting fatigue and restrictions by the track system.

For this purpose, the invention aims at a naughty of the aforementioned type, characterized by the fact that the resilient plate has a dynamic stiffness k2 between 6 kN / mm and 10 kN / mm, preferably between 6 kN / mm and 8 kN / mm.

According to other features of the invention:

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the resilient plate comprises a substantially flat upper face and a substantially flat bottom face;

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he block comprises four peripheral faces that connect the face superior to the inferior face, comprising the naughty ones resilient segments arranged between each peripheral face of the block and peripheral flange of the shoe;

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the resilient segments comprise at least two resilient segments lengths whose dynamic stiffness is between 20 kN / mm and 25 kN / mm, and at least two transversal resilient segments whose dynamic stiffness is between 15 kN / mm and 18 kN / mm;

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bliss Naughty comprises, on the upper face of the rigid block, a resilient support element whose dynamic rigidity is comprised between 120 kN / mm and 300 kN / mm, preferably between 200 kN / mm and 300 kN / mm, providing the resilient support element to receive the rail supported;

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the Naughty comprises a single block and a single shoe;

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he block has a mass between 350 kg and 450 kg, preferably between 400 kg and 450 kg;

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the Naughty comprises two blocks, two shoes respectively associated and a cross brace that joins the two blocks; Y

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every block has a mass between 100 kg and 150 kg, preferably between 130 kg and 150 kg.

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The object of the invention is also a section of railway track characterized by the fact that it comprises a Naughty as described above and at least one rail supported Over the naughty

The invention will be better understood with reading of the following description, given by way of example, and made referring to the drawings, in which:

- Figure 1 is a schematic view in cross section of a section of railway track according to a first mode of realization;

- Figure 2 is a more schematic view detailed in cross section of the crossbar of figure 1;

- Figure 3 is a schematic view in longitudinal section of the crossbar of figures 1 and 2;

- Figure 4 is a scheme that models the railway track section of figure 1;

- Figure 5 is a graph illustrating the acoustic performance of a sleeper according to the invention; Y

- Figure 6 is a view similar to that of the Figure 1 of a section of railway track according to a second mode of realization.

A section of railway track 2 according to a first mode of embodiment of the invention is schematically illustrated in the Figure 1. Section 2 comprises two longitudinal rails 4 fixed to a sleeper 8. The sleeper 8 comprises a single rigid block of cement 9 and two resilient support elements 10 arranged between each rail 4 and block 9.

By convention, the longitudinal rails 4 define a longitudinal direction reference.

The resilient support elements 10 have a noticeably parallelepiped shape. In the example illustrated in Figure 1, its width is substantially equal to the width of the base of a rail 4, and its length is substantially equal to the block width 9.

The resilient support elements 10 are housed in a respective recess 12 of block 9. The profile of each Notch 12, in cross section, is substantially rectangular. The width and length of each recess 12 are, in the example illustrated in figure 1, substantially equal to the width and the length of a resilient support element 10, respectively.

The resilient support elements 10 are about example glued to the naughty 8.

Each rail 4 is connected to block 9 by rail staples (not shown) that prevent any transverse displacement of the rail with respect to block 9 and that solidarity rail 4 to block 9 and each support element resilient 10.

In all that follows, considering the range of considered frequency (less than or equal to 250 Hz), any Dynamic rigidity is considered as constant and substantially equal to 130% of static stiffness.

The resilient support elements 10 form a first elastic level 14 of vertical dynamic stiffness k1 such as is modeled in figure 4. Indeed, each rail 4 is modeled as being suspended at a first end of a spring 16 of dynamic stiffness k1. The second end of the spring 16 is attached to the block 9.

Each resilient support element 10 has a dynamic stiffness k1 between 120 kN / mm and 300 kN / mm, preferably between 200 kN / mm and 300 kN / mm. The material used for each resilient support element 10 is for example rubber, polyurethane or any other resilient material.

The crossbar 8 of Figure 1, illustrated by detailed way in figures 2 and 3, it comprises a shoe 20 intended to receive block 9, a resilient plate 22 arranged in a substantially horizontal plane between block 9 and the shoe 20, and four resilient segments 24, 26 arranged in one plane substantially vertical between block 9 and shoe 20.

Block 9 has a noticeably shaped parallelepipedic and essentially comprises an upper face 32, a substantially flat bottom face 34 that serves as a support, and four peripheral faces 36, 38 that join the upper face 32 to the lower face 34 by respectively a rounded 44 and a bezel 46. The peripheral faces 36, 38 comprise two faces longitudinal peripherals 36 and two transverse peripheral faces 38.

The peripheral faces 36, 38 each comprise a substantially flat bottom 36A, 38A, a top noticeably flat 36B, 38B, and an intermediate part noticeably flat 36C, 38C joining each bottom 36A, 38A in its part respective upper 36B, 38B. The longitudinal upper parts 36B and transverse upper parts 38B converge with each other upwards. The longitudinal lower parts 36A and the parts Transverse bottoms 38A converge mutually downward. The longitudinal intermediate parts 36C and intermediate parts 38C transverse converge downwards forming a angle with respect to the vertical plane greater than each lower part respective 36A, 38A.

Block 9 is chosen with a dough especially high. Indeed, its mass is between 350 kg and 450 kg, preferably between 400 kg and 450 kg. The increase in mass of block 9 is obtained classically by attachment of elements metal in the cement.

The shoe 20 consists of a helmet noticeably rigid. The shoe 20 essentially comprises a bottom 48 and a continuous peripheral flange 50 that borders the bottom 48.

The bottom 48 has an upper face 52 noticeably flat and rectangular.

The peripheral flange 50 of the shoe 20 It comprises four panels 54, 56. The four panels 54, 56 they comprise two longitudinal panels 54 associated respectively with the longitudinal faces 36 of block 9 and two panels cross sections 56 associated respectively to the cross faces 38. Each panel 54, 56 comprises a respective inner face 62, 64. Each inner face 62, 64 comprises a housing 66, 68 noticeably parallelepiped destined to receive each one about resilient segments 24, 26.

Accommodations 66, 68 are noticeably parallel to the respective lower parts 36A, 38A of the faces peripherals 36, 38 of block 9. Each housing 66, 68 has a rectangular periphery defined by a peripheral flange continuous 66A, 68A. Each accommodation 66, 68 also has substantially the same height and substantially the same length as the lower part 36A, 38A with which it is associated.

Each inner face 62, 64 comprises a part upper 62A, 64A flat and whose inclination with respect to the vertical is substantially equal to or greater than the inclination of the respective intermediate parts 36C, 38C of the peripheral faces 36, 38 of block 9. The upper parts 62A, 64A have substantially the same height as the intermediate parts respectively associated 36C, 38C of block 9.

The upper parts 62A, 64A of the faces internal 62, 64 of panels 54, 56 are connected to an edge continuous upper 70 of flange 50. The upper edge 70 has, in the example illustrated in figures 2 and 3, two fingers that allow a continuous seal 72 to be fixed. The joint 72 is for example of natural or synthetic rubber. This creates a tightness between block 9 and shoe 20 without harming the displacement of block 9 in shoe 20. It is also possible make the seal 72 by casting a material as a silicone or a polyurethane, in the form of a cord continuous.

The stiffness of the shoe 20 is reinforced by means of ribs 74 arranged in relief on the outside of panels 54, 56, and, in part, under the bottom 48. They come, by example, of matter of the shoe itself 20. These ribs 74 may present any appropriate form and any provision appropriate with respect to shoe 20, in a manner known in the state of the art, especially by EP-A-0 919 666. They present, in the example illustrated in figures 2 and 3, notches 76 that allow anchor the shoe 20 to an armor. The ribs 74 are, during the placement of the track, submerged at least partially in the cement. In this way they guarantee the solidarity of the shoe 20 with the cement filling.

In the example illustrated in Figures 2 and 3, the Shoe 20 is made of one piece, by molding. No way illustrated, shoe 20 is made by assembling several shells partials as is known in the prior art (for example EP-A-0 919 666). If of a sleeper 8 monobloc according to the first embodiment of the invention can be for example two semi-end shells and a central hull that joins the two semi-end shells.

The shoe 20 is made for example of matter molded thermoplastic or resin cement.

The resilient plate 22 has a shape noticeably parallelepipedic and upper and lower faces substantially flat to minimize mechanical constraints suffered from resilient plaque 22 and avoid the problems of fatigue. Its length and width are substantially equal respectively to the length and width of the lower face 34 of block 9.

Its thickness is between 10 mm and 20 mm, preferably between 16 mm and 20 mm. The resilient plate 22 it remains like this in an elastic interval, which corresponds substantially at a maximum strain rate less than or equal to 40% The strain rate is the thickness variation rate of resilient plate 22 between a free state and a state in load.

The resilient plate 22 forms a second level elastic 78 of vertical dynamic stiffness k2 as modeled in Figure 4. Indeed, rigid block 9 is modeled as being suspended on the first ends of two springs 80 of dynamic stiffness k2. The second ends of the docks 80 They are attached to shoe 20.

The resilient plate 22 according to the invention has a dynamic stiffness lower than the dynamic stiffness of Classically used devices. Effectively stiffness dynamic is between 6 kN / mm and 10 kN / mm, preferably between 6 kN / mm and 8 kN / mm.

The resilient plate 22 is made for example of a cellular elastomeric material.

According to a preferred embodiment, the plate resilient 22 has a dynamic vertical stiffness k2 noticeably uniform on the whole of its surface.

In another embodiment, the resilient plate 22 has, in a central area of block 9, a dynamic stiffness vertical k3 less than or equal to k2. The central zone comprises the middle of block 9 and extends transversely from the middle of block 9 made the ends about substantially half of the block surface 9. Indeed, being this central area less requested, it is possible to use one more material for this elastic and therefore less expensive.

The resilient plate 22 can rest freely on the bottom 48 of the shoe 20. In this way, you can easily remove from shoe 20.

Advantageously, the cross member 8 comprises also a cove of thickness 82 noticeably incompressible, such as illustrated in figures 2 and 3.

The thick cove 82 has a shape noticeably parallelepipedic. Its length and width are substantially equal to the length and width of the face upper 52 of the bottom 48 of the shoe 20. Its thickness is lower or equal to 10 mm, and is preferably between 2 mm and 4 mm

The thick cove 82 rests freely on bottom 48 of shoe 20. In this way, it can be removed easily from shoe 20, or be added to shoe 20, to adjust the level of the track.

Advantageously, the resilient plate 22 rest freely on the thick cove 82.

The surface of the thick cove 82 has a roughness high enough to prevent slippage of the resilient plate 22 in the shoe 20. The roughness is obtained by example by stretch marks, diamond tips or spikes.

Each resilient segment 24, 26 presents a external face 24A, 26A, an internal face 24B, 26B and four faces peripherals

The external faces 24A, 26A and internal 24B, 26B they have substantially the same dimensions and have an outline substantially rectangular.

The external faces 24A, 26A and internal 24B, 26B they have a substantially equal length and width respectively to the length and width of the housings respective 66, 68 of the peripheral flange 50 of the shoe 20.

Resilient segments 24, 26 are arranged in the respective housings 66, 68. For example, maintained thanks to friction between the peripheral faces of resilient segments 24, 26 and peripheral flange 66A, 68A of each housing 66, 68. Thus, the resilient segments 24, 26 can be easily removed.

The retention of each resilient segment 24, 26 It can also be secured by mutual curling. For example, the housings 66, 68 comprise grooves and segments resilient 24, 26 comprise grooves complementary.

Resilient segments 24, 26 have a thickness greater than the depth of the housings 66, 68 of such so that they protrude with respect to flanges 66A, 68A.

Internal faces 24B, 26B are in support simple against the respective lower parts 36A, 38A of the peripheral faces 36, 38 of the rigid block 9.

As illustrated in Figures 2 and 3, the internal faces 24B, 26B are provided with grooves that increase their elasticity.

The resilient segments 24, 26 have a dynamic stiffness between 12 kN / mm and 25 kN / mm. Is it so made, for example, of rubber, polyurethane or any other resilient material

The corresponding longitudinal segments 24 to the longitudinal peripheral faces 36 are subjected to about efforts greater than cross segments 26 corresponding to the transverse peripheral faces 38. Also, the longitudinal segments 24 can be chosen advantageously with a dynamic stiffness superior to that of cross segments 26. Thus, the segments longitudinal 24 have for example a dynamic stiffness between 20 kN / mm and 25 kN / mm, while the segments transverse 26 have a dynamic stiffness between 15 kN / mm and 18 kN / mm.

Under normal operating conditions, the resilient segments 24, 26 keep block 9 at a certain distance of the inner faces 62, 64 of the shoe 20.

The resilient segments 24, 26 thus allow a horizontal damping of block 9. This damping horizontal is decoupled from the vertical damping obtained thanks to the resilient support elements 10 and the plate resilient 22.

It will be noted that the number of resilient segments It is not limiting. The sleeper 8 may for example comprise, to each side of block 8, two transverse segments 34 one next to each other of the other.

Figure 5 illustrates the acoustic performance of a sleeper according to the invention and of a known sleeper. The Figure 5 represents an insertion gain as a function of the frequency. Insertion gain is here the ratio expressed in dB between the value of a metric quantity (velocity, acceleration, force, etc.) obtained with the introduction of a resilient plate and the one obtained without it (see NF ISO 14837-1: 2005). In the example considered, it is of the force exerted on the shoe 20. A reduction in the value of the metric magnitude will be expressed by a negative sign of the insertion gain

In addition, the cutoff frequency is the frequency from which a decrease of the global insertion gain

k1 dyn is the dynamic stiffness of the elements Resilient support 10, dyn is the dynamic stiffness of the plate resilient 22, M is the mass of block 9.

The curve illustrating the insertion gain as a function of the frequency for k2dyn = 21.3 MN / m, M = 200 kg, k1dyn = 150 MN / m constitutes a reference curve S1 illustrating the performance of the known device. A second curve illustrates the performance of a sleeper according to the invention whose k2dyn = 8 MN / m, M = 400 kg and
k1dyn = 270 MN / m.

Between 0 and 10 Hz, the attenuation performance of the vibrations are substantially the same. Between 10 and 25 Hz, the insertion gain is higher by some dB with respect to the curve S1. Between 25 Hz and 250 Hz, the insertion gain is lower by several dB with respect to the S1 curve.

In addition, the cutoff frequency is lower with with respect to the S1 curve (20 Hz instead of 32 Hz).

Thus, between 25 Hz and 250 Hz, the benefits of a sleeper according to the invention are substantially top.

In a second embodiment illustrated in Figure 6, the cross member 108 comprises two rigid blocks 109 joined by a tie 184. To the extent that the naughty bibloque 108 has great similarities with the naughty monobloc 8, it they have, in figure 6, the same references as in Figures 1 to 4, however increased by 100.

The length of the shoes 120 is adapted to receive blocks 109. The same goes for segments cross sections 126 and resilient shoes 122. Figures 2 and 3, illustrating a naughty monoblock 8, they also constitute a Perfect illustration of a naughty 108.

The main difference between the naughty monobloc 8 and the naughty bibloque 108 resides in the presence of a strap 184 that penetrates the two blocks 109.

The decrease in dynamic stiffness K2 of resilient shoes 122 and / or increase in block mass 109 generate a high longitudinal flexion moment.

Also, the strap 184 has a shape adapted to obtain high inertia. It is for example of a square or cylinder shape. The strap 184 also has, for example, a section between 800 mm2 and 1500 mm2 and a thickness between 6 mm and 10 mm. It's done, for example, of steel according to EN 13230-3.

Each block 109 has a mass between 100 kg and 150 kg, preferably between 130 kg and 150 kg.

It will be noted that the naughty monobloc 8 supports especially easily the additional mechanical restrictions resulting from the invention.

It will be understood that with a naughty according to the invention, the decrease in dynamic stiffness k2 of the plate resilient 22, 122 allows to obtain better performance of vibration attenuation, especially reducing the frequency cutting and insertion gain between 25 Hz and 250 HZ.

The increase in the mass of block 9, 109 allows also, for a dynamic stiffness of resilient plate 22, 122 determined, lower the cutoff frequency and therefore improve the performance of the sleeper 8, 108 at low frequencies. Without However, above a certain mass, the restrictions mechanics suffered by the naughty 8, 108 become too much high.

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The increase in dynamic stiffness k1 of resilient support elements 10, 110 lowers the gain of insertion between 200 Hz and 250 Hz and shifts the frequency of resonance at higher frequencies, being the frequency of resonance that for which it is observed that the gain of insertion increases again.

Therefore, the invention allows to approach vibration damping performance obtained with a slab floating whose cutoff frequency is between 14 Hz and 20 Hz and whose insertion gain at -25dB is 63 Hz.

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References cited in the description

This list of references cited by the applicant is intended solely to help the reader and not It is part of the European patent document. Although it has been put maximum care in its realization, errors cannot be excluded or omissions and the EPO declines any responsibility to respect.

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Patent documents cited in the description

EP 0919666 A [0003] [0032] [0033]

Claims (10)

1. Naughty (8; 108) railroad, of the type which includes:

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a rigid block (9; 109) having a lower face (34), and a upper face (32) intended to receive at least one rail longitudinal (4; 104),

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a shoe (20; 120) intended to receive the rigid block (9; 109) and constituted by a rigid helmet provided with a bottom (48; 148) and a peripheral flange (50; 150) that borders this bottom (48; 148),

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a resilient plate (22; 122) disposed between the bottom face (34) of the rigid block (9; 109) and the bottom (48; 148) of the shoe (20; 120), characterized by the fact that the resilient plate (22; 122) has a dynamic stiffness k2 comprised between 6 kN / mm and 10 kN / mm, preferably between 6 kN / mm and 8 kN / mm.

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2. Naughty (8; 108) according to claim 1, characterized in that the resilient plate (22; 122) comprises a substantially flat upper face and a substantially flat lower face. 3. Naughty (8; 108) according to claim 1 or 2, characterized in that the block (9; 109) comprises four peripheral faces (36, 38) connecting the upper face (32) to the lower face (34), the cross member (8; 108) comprising resilient segments (24, 26; 124, 126) arranged between each peripheral face (36, 38) of the block (9; 109) and the peripheral flange (50; 150) of the shoe (20; 120). 4. Naughty (8; 108) according to claim 3, characterized in that the resilient segments (24, 26; 124, 126) comprise at least two longitudinal resilient segments (24; 124) whose dynamic stiffness is comprised between 20 kN / mm and 25 kN / mm, and at least two transverse resilient segments (26; 126) whose dynamic stiffness is between 15 kN / mm and 18 kN / mm. 5. Naughty (8; 108) according to any of the preceding claims, characterized in that it comprises, on the upper face (32) of the rigid block (9; 109), a resilient support element (10; 110) whose Dynamic stiffness is between 120 kN / mm and 300 kN / mm, preferably between 200 kN / mm and 300 kN / mm, the resilient support element (10; 110) being provided to receive the rail (4; 104) supported. 6. Crossbar (8) according to any of the preceding claims, characterized in that the crossbar (8) comprises a single block (9) and a single shoe (20). 7. Naughty (8) according to claim 6, characterized in that the block (9) has a mass between 350 kg and 450 kg, preferably between 400 kg and 450 kg. 8. A cross member (108) according to any one of claims 1 to 5, characterized in that the cross member (108) comprises two blocks (109), two respectively associated footings (120) and a crossbar (184) that joins the two blocks (109). 9. Naughty (108) according to claim 8, characterized in that each block (109) has a mass between 100 kg and 150 kg, preferably between 130 kg and 150 kg. 10. Section of railway track (2; 102), characterized in that it comprises a crossbar (8; 108) according to any of the preceding claims and at least one rail (4; 104) resting on the crossbar (8; 108) ).