Title of Invention

A CONCRETE SLEEPER FOR A RAILWAY TRACK WITH MONOBLOCK OR DOUBLE BLOCK SLEEPERS

Abstract

A concrete sleeper for a railway track with monoblock sleepers or double block sleepers characterised in that at least one projecting concrete block (7, 7',7", 7"') is provided integrally on the lower side of each concrete sleeper block (2,3) and reinforcements are embedded in the concrete sleeper with part of the reinforcements (4) projecting out from the lower side of the concrete sleeper blocks (2,3) wherein the height of the projecting concrete block (7, 7',7", 7"') is more than the length of the projecting part of the reinforcements (4) below the concrete sleeperm (1) allowing placing of the concrete sleeper block on a support layer (5)before alignment and embedding in concrete mass.

Full Text

The invention relates to concrete sleepers for a fixed railway track. A reinforcement part projects out below from a partly constructed concrete shell, so that it can anchor into the cast mass after alignment on a covering layer. Sleepers with reinforcements and their installation in a fixed rail track has been described in the German Patent No.DE 19653 858. For the purpose of installation the concrete sleepers carrying the tracks or the auxiliary tracks are pre-assembled to a track grate over which a carrier layer is created mostly as a non-reinforced, compressed concrete in which the layers and height are adjusted and is finally embedded in a cast mass. Due to a projection of part of the reinforcement downwards form the partially concrete embedded sleeper bodies, an intimate anchoring of the sleepers in the concrete mass occurs. This provides a significantly higher stability to the fixed rail track when laid. However during installation of a fixed railway track using the sleepers known in the prior art, the track grates delivered or assembled on site have to be aligned and cast over a carrier layer immediately on delivery, in order to avoid damage to the part of the reinforcement projecting downwards by bending while placing on the carrier layer during lifting up and alignment. The installation work would be significantly simpler, if one could temporarily place down the finished track grates initially on a support layer, in order to lift them up using a machine such as a portal crane subsequently, align them and then embed them in the concrete mass. The invention provides a concrete sleeper, which can be temporarily placed down and subsequently installed. The track grates with the part of the reinforcement of the sleepers projecting downwards can be placed down easily on to a supporting layer when the sleepers according to the invention is used in the installation. The invention also provides a method of installation of these sleepers to form the fixed railway track. At the lower side of the concrete sleeper at least one concrete block is formed with part of a reinforcement projecting downwards. Since the projected part of the reinforcement do not touch the support when it is placed on the support, since height of the concrete block formed on the lower side of the concrete sleeper is more than the projected part of the reinforcement. The concrete blocks have an area that is relatively smaller than the base area of the concrete sleeper so that a larger part of the reinforcement projects freely below and can be embedded in the concrete mass during installation. Another longitudinal reinforcement can also be provided with the projecting reinforcement. The provision of such concrete blocks clearly facilitates a smooth placement of the sleepers, and prefabricated track grates made from such sleepers, either near the construction site or on the carrier layer of the travelling line without any damage to the projecting reinforcement. In the concrete sleeper according to the invention the concrete blocks should also be made with the provision to accommodate dowels for fixing the rails. These dowels for fixing rails are embedded in the concrete blocks so that they also do not get damaged during installation. In order to reduce the area of concrete blocks inspite of accommodating the dowels several spaced concrete blocks surrounding each dowel may be provided. Thus these concrete blocks may have an inverted conical or pyramid shape. The sleepers according to the invention can be used with tracks using either single block sleepers or double block sleepers. The use of concrete sleepers according to the invention with the concrete blocks and finished track grates with such sleepers can be optimised in the following manner while using with double block sleepers. Each single block of a double block concrete sleeper is extended at least on one side of the rail seating to provide a walkable surface area. In this extended area of the stepping surface, dowels can be provided for clamping extra components such as intercepting devices, receiving devices, guiding devices, compensating rails during transition from a fixed track to a ballasting track and current carrying conductors. The reinforcements preferably can be in the form of bars, preferably plates with a high edge, U-shaped or angular profile rails, lattice carriers, punched profiles, sheet metals and the like. The type of reinforcements can be continuous and from the reinforcement cages. What is important is that a part of each reinforcement projects out below from the concrete sleeper body of the individual sleeper blocks of a double block sleeper. Preferably the projecting section and the type of the design of the reinforcement may be selected so that longitudinal reinforcement members may be inserted parallel to the traversing rails in the projecting part of the reinforcement. All the above features can be incorporated in a railway track with single block concrete sleepers also. The invention provides a concrete sleeper for a railway track with monablock sleepers or double block sleepers characterised in that at least one projecting concrete block is provided integrally on the lower side of each concrete sleeper blocks and reinforcements are embedded in the concrete sleeper with part of the reinforcements projecting out from the lower side of the concrete sleeper blocks wherein the height of the projecting concrete block is more than the length of the projecting part of the reinforcements below the concrete sleeper allowing placing of the concrete sleeper block on a support layer before alignment and embedding in concrete mass. The invention also provides a method of installing of a fixed rail track, in which the concrete sleepers according to the invention are intially pre assembled to a track grate and men adjusted over a supporting layer as per the position and embedded into a concrete mass. The track grate is placed initially on to the carrier layer resting on the concrete blocks provided below the sleeper, before the alignment and then a preliminary alignment is carried out. Preferably the longitudinal reinforcement running parallel to the tracks can be loosely inserted into the open part of the projecting reinforcement below the concrete sleeper. By placing the track grate the reinforcements can be tightened and neighboring track grates can be bridged before the alignment. The placement of the sleepers on to the supporting layer is done preferably by inserting a polyethylene foil or sheet which is removed before casting after the alignment of the track grate. The concrete sleepers and their installation will be described with reference to the accompanying drawings. Fig. 1 shows a view of a double block sleeper on a carrier layer for a fixed rail track. i Fig. 2 shows an enlarged view of a section along the line Fig. 3 shows an enlarged bottom view of one of the blocks of the double block sleeper shown in figure 1 showing only the reinforcement. Fig. 4 shows a lateral view of one of the sleeper blocks of a doubic block sleeper according to the invention with two concrete blocks covering each one of the rail-clamping dowels respectively. The double block sleeper 1 consists of two partly concrete embedded individual sleeper blocks 2 and 3 in which the reinforcement passes through the space formed between the sleeper blocks 2 and 3. The individual sleeper blocks 2 and 3 are only partly embedded in concrete so that the reinforcement 4 partly project out downwards from the sleeper blocks 2 and 3. After the alignment of a track grate from such sleeper blocks with the rails fixed on it over a solid carrier layer 5, the projecting reinforcement parts are embedded in concrete casting layer 6 providing an intimate bonding between the concrete cast layer 6 and the sleepers. The sleeper blocks 2 and 3 are provided with projecting concrete blocks 7 at the lower side. During installations the concrete blocks 7 project more than the lowest end of the reinforcement 4 since these concrete blocks are provided with a projection more than projecting length of the reinforcement 4. The track grate made of rails and the double block concrete sleepers may be placed after transporting to the site on to the carrier layer 5 for carrying out preliminary alignment. Each track grate can be raised, aligned and embedded into the concrete casting layer 6 with the help of lifting devices, such as portal cranes or similar equipments. The track grate can be placed on the projecting concrete block 7 without damaging of the reinforcement 4 projecting downwards. Even driving on the track grate is possible before embedding in the cast concrete particularly when broad sleepers are being used. A polyethelene foil or sheet 8 is preferably inserted between the projecting concrete blocks 7 and the carrier layer 5 during installation and is removed when the track grate is lifted for the purpose of alignment. Preferably the transverse reinforcement 9 are provided connecting to the reinforcements 4 projecting from the lower part of the sleeper block 2 and 3 and longitudinal reinforcements 10 lies on the transverse reinforcements 9. The insertion of the longitudinal reinforcements 10 is thus simplified by the fact that initially, the track grate may be placed down on the carrier layer 5. In this resting position the insertion of the longitudinal reinforcements 10 may be carried out easily. Reinforcements 11 may preferably be provided in the concrete sleeper blocks when they are made for preventing shrinkage cracks in the concrete casting layer. A concrete trough or laterally moving shells may be provided to prepare the track grates. The projecting concrete blocks 7 may have any suitable shape such as a cuboid, rectangular or truncated cone and have a width equal to less than the width of the sleeper blocks 2 and 3. It is important mat the projecting concrete blocks 7, T are made in such a manner that they folly cover the dowel 12 for rail clamping in order to avoid damage to reinforcements 4 during the alignment and concrete embedding. Figs. 3 and 4 show a preferred way for using each sleeper block 2, 3 of a double block concrete sleeper in which each of the two projecting concrete blocks T\ 7'" covers the rail clamping dowels 12. For the sake of simplicity, two different shaped namely a conical stump and a trapezium shape of projecting concrete blocks are shown in one and the same fig. 3. However one can certainly select one type of the projecting concrete blocks 7", 7'". The projecting concrete blocks 7 has relatively small volume and small area compared to the sleeper blocks 2, 3 and the part of the reinforcements 4 below the individual sleeper blocks 2, 3 project out for embedding into the concrete casting mass 6. It ensures that the concrete casting mass covers the concrete blocks 7, 7', 7", 7'" due to lateral flow below the concrete sleepers 2,3 without leaving any open space. A step-on area 13 may be provided to the left and the right of the rails with sufficient breadth, so that before the filling of concrete mass one can walk over the track grate placed on the covering layer 5. To avoid stepping on the reinforcements laid between the concrete sleepers 2 and 3, extended walking stepping area 13 may be provided on at least one side of the rail seating 14. Dowel placement bores 15 and 16 are provided in said extended walking area 13 for future assembly of intercepting devices, guiding devices, compensating rails during the transition of a fixed track to a blasting line and for current carrying conductors. In the concrete sleepers according to the invention many type of reinforcements may be used such as high-edged plates which are U-shaped or with angular profile rails. The concrete sleeper according to the invention can be used with rails with single block sleepers or double block sleepers. The use of partly concrete filled sleepers with projecting concrete blocks are equally good for mono block sleepers with reinforcements projecting downwards. The use of concrete sleepers according to the invention makes installation of rails easy and cost effective. WE CLAIM : 1. A concrete sleeper for a railway track with monoblock sleepers or double block sleepers characterised in that at least one projecting concrete block (7, 1\ 7", 7'") is provided integrally on the lower side of each concrete sleeper block (2, 3) and reinforcements are embedded in the concrete sleeper with part of the reinforcements (4) projecting out from the lower side of the concrete sleeper blocks (2, 3) wherein the height of the projecting concrete block (7, 7\ T\ 7"') is more than the length of the projecting part of the reinforcements (4) below the concrete sleeper (1) allowing placing of the concrete sleeper block on a support layer (5) before alignment and embedding in concrete mass. 2. The concrete sleeper as claimed in claim 1, wherein in the said projecting concrete block (7, 7\ T\ 7'") dowels (12) for clamping the .rails are fully embedded. 3. The concrete sleeper as claimed in claim 1 or 2, wherein the said projecting concrete block (7, 7', 7", 7'") has a narrower width than the width of the concrete sleeper blocks (2,3). 4. The concrete sleeper as claimed in claims 2 or 3, wherein plurality of projecting concrete blocks (7", 7'") are provided covering the dowels (12) for clamping the rails. 5. The concrete sleeper as claimed in anyone of the previous claims, wherein the said projecting concrete blocks (7, 7', 7', 7'") have the shape of truncated cone or truncated pyramid. 6. The concrete sleeper as claimed in anyone of the previous claims, wherein the said concrete sleeper blocks (2, 3,) have an extended length at least on one side of rail seating (14) to provide a walkable surface area (13). 7. The concrete sleeper as claimed in claim 6, wherein in the said walkable surface area (13) dowel bores (15) are provided for fixing additional components such as intercepting devices, guiding devices or compensating rails. 8. The concrete sleeper as claimed in anyone of the previous claims, wherein the reinforcements ( 4) are made of iron and selected from rods, plate, rails with U-shaped profile or angular profile, lattice carriers, punched profiles and sheets. 9. A method of installing a fixed rail track using concrete sleepers as claimed in anyone of the previous claims comprising the steps of transporting the said concrete sleeper blocks (2, 3) and placing them on a support layer (5), aligning them to form a track grate, filling the space below the sleeper block and carrier with concrete covering the projected part of the reinforcement (4) to embed the track grate in concrete to provide a fixed rail track. 10. The method as claimed in claim 9, wherein the said track grate is formed with single block concrete sleepers. 11. The method as claimed in claim 9, wherein the said track grate is formed with double block concrete sleepers. 12. A concrete sleeper, substantially as hereinabove described and illustrated with reference to the accompanying drawings.

Documents:

095-che-2003-claims.pdf

095-che-2003-correspondnece-others.pdf

095-che-2003-correspondnece-po.pdf

095-che-2003-description(complete).pdf

095-che-2003-drawings.pdf

095-che-2003-form 1.pdf

095-che-2003-form 13.pdf

095-che-2003-form 26.pdf

095-che-2003-form 3.pdf