Railway turn out

Abstract

A railway turnout includes conventional rail components (10) which are mounted to cross ties (12) having a top plate (20). Stirrups (22) depend downwardly from the top plate (20). Continuous tubular elements pass through the stirrups (22) and these elements are pumped with concrete to form continuous longitudinal beams which support the components (10).

Description

TECHNICAL FIELD OF THE INVENTION

[0001] This invention relates to a railway turn out.

BACKGROUND ART

[0002] The conventional turnout is based on the use of sleepers (steel, wood or concrete) supported on ballast. This is based on the conventional dynamic system of railway track engineering which results in the loss of required geometry for safe passage of trains, therefore requiring frequent maintenance to the turnout.

[0003] Another disadvantage of the conventional turnout is that at the critical places, (switch area, crossing area) the position of the sleepers and the general design of the sleeper layout makes efficient maintenance very difficult and costly. Most railways spend the biggest part of their maintenance budget on expensive machinery to constantly address these issues.

[0004] Yet another disadvantage of the conventional turnout is that the support at the critical crossing point the sleeper support is usually not sufficient, resulting in bending of the sleepers and thus permanent loss of geometry.

[0005] A further disadvantage of the conventional turnout is the contamination of the ballast and the difficulty and high cost of screening and replacing the ballast which is required to support the turnout.

[0006] Other disadvantages of the conventional turnout include the difficulty in securing good drainage to the turnout area resulting in the contamination and collapse of the supporting formation below the turnout; the fact that the total mass and volume of the turnout (rail sections, sleepers and ballast) is very great and calls for big resources and cost during replacement; and the fact that the sleepers support the rail section only at intervals thus requiring bigger rail sections for higher axle loads.

[0007] It is an object of the present invention to minimise and even eliminate some or all of the above disadvantages.

DISCLOSURE OF THE INVENTION

[0008] According to the invention a railway turn out includes rail components mounted to cross ties, the components being adapted to be supported longitudinally on concrete beams.

[0009] In a preferred form of the invention the concrete beams are cost in situ by forming a continuous tubular element and filling the tubular element with concrete to abut the rail components or a structure associated with the components.

[0010] In one form of the invention the rails are supported on stirrup formations which comprises open bottom channels of steel. The continuous tubular element passes through the stirrup.

[0011] The stirrups may depend downwardly from a transverse plate which serves to support the rail connection (clip).

[0012] The stirrups may be separated by a I beam.

[0013] In an important aspect of the invention a series of resilient pads, or preferably a continuous resilient pad is provided beneath the rails. This serves to distribute stress and shock waves.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Embodiments of the invention are described below with reference to the accompanying drawings in which:

[0015] FIG. 1 is a plan view of a turn out according to the invention;

[0016] FIG. 2 is a section along the line A A of FIG. 1;

[0017] FIG. 3 is a section along the line B B of FIG. 1;

[0018] FIG. 4 is a section along the line C C of FIG. 1;

[0019] FIG. 5 is a plan view of the tubular concrete beams,

[0020] FIG. 6 is a plan view of a completed turn out;

[0021] FIG. 7 is an enlarged view of a slide plate indicated by X in FIG. 2; and

[0022] FIG. 8 is a sectional view of shuttering for use in the casting of the tubular beams.

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] In FIG. 1 a turn out includes rail components 10 which are held in the exact geometric configuration by cross ties 12 which, in the switch zone 14 are wider than those in the leads and closures zone 16 and the crossing zone 18 because of the critical conditions of that zone.

[0024] The cross ties have a continuous transverse top plate 20 (see FIGS. 2, 3 and 4) from which depends stirrups 22, the number of which correspond to the rail configuration at the particular zones.

[0025] Reinforcing I-beams 24 are provided between adjacent stirrups. The top plates 20 support the set rails with conventional rail clips 24 or special clips 26 as shown in FIGS. 2 and 7 for the slide plates.

[0026] The turn out may be transported in its three zones which is a distinct advantage over the conventional turn outs which are very heavy.

[0027] Before the turnout is located the exact zone must be constructed to minimum design parameters based on the axle loads and traffic volumes to ensure the long life of the total system.

[0028] The turnout components are assembled on a prepared formation as indicated on FIG. 1. The tubular elements are then placed in position (as indicated by 22). The whole turnout is then aligned to the required final position and the tubular element is pumped with concrete.

[0029] Reference to FIG. 5 indicates the general arrangement of the trenches and tubular elements 28. The turn out is then placed and aligned to the required final position and the tubular element is pumped with concrete under pressure.

[0030] A continuous pad 32 is placed between the bottom of the rails and the top of the tubular element.

[0031] In FIG. 8 a shutter 40 is shown which is held in position by a frame 42 and shutter lugs 44. A tubular element 50 is filled with concrete under pressure and assumes the shape as shown.

Claims

1. A railway turnout including rail components mounted to cross ties and supported by concrete beams, characterised in that the components are adapted to be supported longitudinally on tubular concrete beams.

2. The railway turn out according to claim 1 characterised in that the longitudinal concrete beams are case in situ by forming a continuous tubular element and filling it with concrete to abut the rail components or a structure associated with the components.

3. The railway turnout according to claim 2 characterised in that the rails are supported on stirrup formations comprising open bottom channels and the continuous tubular elements pass through the stirrups.

4. The railway turnout according to claim 3 characterised in that the stirrups depend downwardly from a transverse plate which serves to support a rail connection.

5. The railway turnout according to claim 3 or claim 4 characterised in that the stirrups are separated by an I beam.

6. The railway turnout according to any of the above claims characterised in that a series of resilient pads, or a continuous pad is provided beneath the rails.