IMPROVEMENTS IN OR RELATING TO TRACKS FOR RAILWAY TYPE VEHICLES

Abstract: A track (10) for railway type vehicles includes a foundation (11), a track pavement (12) on the foundation (11), and a pair of rails supported by the track pavement (12), characterised in that the track pavement (12) includes a plurality of pre-formed sections (13) laid end to end and connected together.

Description: Title: Improvements in or Relating to Tracks for Railway Type Vehicles Description of Invention This invention relates to tracks for railway type vehicles such as trains and trams. Conventionally tracks have comprised a pair of rails on which the vehicle wheels run, the rails being supported in spaced relationship by sleepers on a base. The sleepers conventionally have rested on a base of ballast. Such conventional tracks require frequent maintenance as the motion of vehicles tends to settle the ballast resulting in the rails becoming out of level and line. It has been proposed to provide a track pavement in a settable material such as concrete or macadam, and to lay the rails on the pavement. The rails have been secured relative to the pavement either on sleepers which each support a pair of rails, or on discrete blocks for individual rails, which sleepers or blocks have been secured to the pavement e.g. by grouting. Alternatively the rails have been secured to the pavement by an elastic adhesive. The pavement has been supported on a prepared base. A track pavement provides an advantage over conventional arrangements in which rails are supported on ballast, in terms of reduced maintenance as loadings imposed on the track as a train or other railway vehicle travels along the track, and particularly peak loadings, are dissipated into the base by the pavement. However there are .drawbacks too, not in the least the necessity for the pavement accurately to be laid so that the rails subsequently supported by the pavement conform to the track engineer's specification of line, level and rail positions. Once laid, it is very difficult to modify the pavement subsequently, for examples to realign the track and/or to change the cant of the track. Another substantial problem is to lay the pavement when only short interruptions in normal railway traffic (possessions) can be tolerated. Ideally a roadway is required adjacent the site where the track is to be provided to allow for delivery of materials for laying the pavement. Alternatively it is necessary to use an adjacent track as a delivery route for materials, which may be acceptable for laying new track, but presents substantial difficulties where possession time available may be short. When forming a pavement on site there may be insufficient time for the concrete/macadam or other material which is laid to produce the pavement, to set. According to a first aspect of the invention we provide a track for railway vehicles including a foundation, a track pavement on the foundation, and a pair of rails supported by the track pavement, characterised in that the track pavement includes a plurality of pre-formed sections laid end to end and connected together. Thus a track may be provided which has all the advantages of a track having a track pavement, but the track may be installed simply and quickly, even where only short possessions are available. The pre-formed sections can be conveniently delivered by road or by a delivery vehicle using an adjacent track and lifted into position from the lorry or railway delivery vehicle using a suitable crane or other lifting means. Most conveniently the sections are generally of channel shape comprising a base in which the rails are supported, and a pair of upstands. Thus the upstands, or at least one of the upstands, may be used for various purposes such as for example only, to accommodate services, such as pipes and/or cables, in which case the upstand may include a suitable hollow such as a duct or pathway for such services. The hollow may be open or may be closed by a cover. Alternatively or additionally, the upstands or other part of the preformed sections may be adapted, e.g. with opening or supporting formations, to support a sign, sensor and the like. The pre-formed sections may be adapted to support sound deflecting or sound absorbing or sound attenuating members e.g. baffles, which reduce sound emanating from the rail interface with the wheels of a railway vehicle. To prevent the, particularly but not exclusively channel shaped, preformed sections becoming waterlogged, the pre-formed sections may be formed such that precipitation drains from the sections when laid. The or at least some of the pre-formed sections may be provided with drainage means which permit water to flow from the pavement, e.g. to the side of the foundation on which the pavement is laid, or to a drain. To enable the sections conveniently and quickly to be coupled together, the pre-formed sections may include coupling means to facilitate their coupling to adjacent pre-formed sections. However the sections may rely on running rails spanning several sections to connect the sections together. In a preferred embodiment, each pre-formed section includes ballast. Thus the levelling of the rails laid on the pavement may be facilitated. Of course to prevent the ballast spilling from the pre-formed sections e.g. as they are lifted into place from a delivery vehicle, some ballast retaining means is required. For example a temporary closure means which is removed as the section is laid and connected to an adjacent section may be provided, or a ballast glue. In each case to prevent the concrete or other material from which the pre-formed sections are made from abrasion by the ballast, if desired a membrane is provided between the material of the pre-formed sections and the ballast. Instead of ballast, the pre-formed sections may include alternative means to facilitate the subsequent laying of rails. For example, the rails may be embedded in and/or supported on a bed of macadam or like suitable material. The pre-formed sections may include support sleepers, or blocks, the sleepers or blocks having fixing means to which the rails may be secured e.g. by grouting, bolting, welding or any other appropriate means, the sleepers or blocks in use lying on or in e.g. the ballast. To enable the positions of such sleepers or blocks in the sections to be determined during manufacture and retained during transport and handling of the sections, each pre-formed section may include temporary alignment means secured to the sleepers or blocks and relative to the sections to retain the sleepers or blocks in a set position prior to laying of the pre-formed sections on the foundation, which temporary alignment means are adapted to be removed prior to the rails being secured to the sleepers or blocks. For example such means may include lengths of service rail, or timber or plastic strips for example, which may be replaced when the running rails on which the vehicle runs, are laid along the track pavement. Although the pre-formed sections may be made from any suitable material, preferably the pre-formed sections are made of reinforced and/or pre- stressed concrete. However the sections may be made of and/or contain other materials. The foundation may be made of and/or be a ballast foundation of a conventional track, the rails and sleepers of which have been removed. The foundation on which the track pavement is provided may thus include ballast and there may be provided between the foundation and the concrete pavement, a membrane to protect the underside of the track pavement from abrasion by the ballast of the foundation. According to a second aspect of the invention we provide a method of providing a track for railway vehicles on a base, characterised in that the method includes laying end to end a plurality of sections of track pavement on the base, the sections each being pre-formed, and connecting the sections together to provide a track pavement, and supporting a pair of rails by the track pavement. A track made by the method may have any of the features of the track according to the first aspect of the invention. According to a third aspect of the invention we provide a pre-formed section for a track according to the first aspect of the invention. The invention will now be described with reference to the accompanying drawing which is a perspective view of a pre-formed section of track in accordance with the invention. Referring to the drawing there is shown a track 10 for a railway vehicle such as a train, tram or the like which may be used to transport passengers and/or goods. The track 10 includes a foundation 11 which could be a foundation laid for the track 10, or an existing foundation of for example, a conventional railway track. The foundation 11 may thus comprise ballast which may be levelled as necessary to receive a track pavement 12 as hereinafter described, so that the track 10 is at a desired level. The track pavement 12 comprises a plurality of pre-formed sections 13, which are laid end to end, and preferably are connected together. Thus the preformed sections 13 are generally elongate and in this example are of generally channel shape in cross section, having a base 14, and a pair of upstands 15,16. At each end of -each pre-formed section 13, there are provided connectors 18 (only shown illustratively in the drawing) by means of which the pavement sections 13 may be connected to adjacent pavement sections 13. The sections 13 are pre-formed in a settable material such as concrete, reinforced or supported macadam or the like, in the channel shape, and the ends of the channels are closed by temporary closure means, such as the closure boards 20 shown in the drawing. These boards 20 are removed from the sections 13 when the sections 13 are laid on the foundation 11. Their purpose is to retain within the channels of the sections 13, ballast 22. In an alternative arrangement, instead of providing boards 20 temporarily to close the channel ends, the ballast may otherwise be prevented from spilling from the section 13 while the section 13 is transported to and laid on the foundation 11, for example by applying a glue to the ballast at least adjacent the channel ends. The ballast 22 may be pre-compacted in any event to facilitate its retention in the sections 13. The track pavement 12 further comprises sleepers 25 on the ballast 22 within the channels of the pre-formed sections 13, on which in use, rails on which railway vehicles run, are supported. The sleepers may be made of concrete, steel or other metal, or even timber as desired. Steel or the like is preferred as less ballast will be required. As seen in the drawings, there are provided temporary service rails 26, 27 which extend only substantially over the length of the section 13. These service rails 26, 27 may be temporary secured to the sleepers 25 so as to maintain the sleepers 25 in their factory set positions during transport of the sections 13 to site, and laying of the sections 13 on the foundation 11. The service rails 26, 27 may need to be secured relative to the sections 13 as the sections 13 are transported and laid. Once the pavement 12 is laid, the service rails 26, 27 are removed, and proper running rails (not shown) which may extend for a substantial number of pre-formed sections 13 lengths, may then be laid on the pavement 12, with the running rails being secured to the sleepers 25. Any suitable kind of fixings may be provided to fix the running rails to the sleepers 25, such as clips, grouting, welding or the like. Instead of providing sleepers 25 in the channels or otherwise of the track pavement 12, blocks, pads or other means may be provided within or on the track pavement 12, to support the running rails. Instead of providing temporary service rails 26, 27 any other means to retain the sleepers 25 or other running rail support means in factory set positions of the pavement 12 may be provided, such as timber or plastic strips. Such temporary means need not be removed if this is not a requirement for laying the running rails. Where the pavement sections 13 are made of concrete, the concrete may be reinforced and/or pre-stressed for strength. If desired, parts of the sections 13, or the entire sections 13 may be made from other materials such as macadam, steel or other metals, or a combination of such materials. For one example of an alternative construction, the base 14 of the channel may be made from concrete, and the upstands 15, 16 from metal, but in each case the section 13 is pre-formed in a factory environment, preferably complete with ballast 22, sleepers 25 or other rail supports. To allow for drainage of water from the channels of the sections 13, each section 13 may incorporate a fall in level along the base 14 so that water e.g. as a result of precipitation, may flow along the pavement 12 to drainage openings (not shown) provided in at least some of the sections 13. Such drainage openings may be connected to a drain or simply allow such water to soak/flow away. It will be appreciated that as the track 10 is subject to loadings in use as a result of railway traffic passing along the pavement, the concrete may become worn by the ballast of the foundation 11 and/or the ballast 22 within the channels. Accordingly, a protective membrane may be interposed between the pavement 12 and the foundation 11 and/or between the ballast 22 of the pavement 12 and the pre-formed sections 13. The ballast 22 of the pavement 12 will be prevented from settling by the upstands 15, 16 of the sections 13. If desired, because the sections 13 are pre-formed, the sections 13 may be formed in a factory environment with additional features. For example the pavement 12 may be provided with a hollow formed by ducts along the sections, in which services such as pipes and/or cable may be laid. Such hollow may be provided within an upstand 15, 16 of the pavement 12, and the hollow may be closed with covers for protection from the weather and tampering. Such covers may span a single or a plurality of the pre-formed sections as desired. Additionally and/or alternatively, the pavement 12, e.g. in one or each of the upper surfaces 30, 31 of the upstands 15, 16, there may be provided formations, such as openings, to receive railway equipment, such as bases to support signs, signalling or control equipment such as sensors, adjacent the running rails, and/or baffles or other sound attenuating or absorbing members which being located close to the running rails, will be operative to affect sound produced as railway vehicles pass over the track 10. The upstands 15,16 or other parts of the pavement 12 may be adapted e.g. by the provision of lifting hooks or the like, to facilitate the laying of the pre-formed sections by lifting the sections 13 from a delivery vehicle and lowering them into position. Provided the foundation 11 is well prepared, a track 10 may rapidly and relatively easily be provided with all the advantages of a track having a pavement, but without the installation difficulties of conventional pavements which are cast or otherwise formed on site. By virtue of the pavement being formed by coupled sections 13, adjustment of the track is facilitated because each section 13 can be adjusted individually, uncoupling a section 13 from adjacent section 13, if necessary. Thus for example the level and/or cant of the track may be adjusted. On initial installation, final adjustment of the track level etc. may be achieved by tamping, as is conventional with conventional ballast and sleeper tracks. Various other modifications may be made without departing from the scope of the invention. The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims: CLAIMS 1. A track for railway vehicles including a foundation, a track pavement on the foundation, and a pair of rails supported by the track pavement, characterised in that the track pavement includes a plurality of pre-formed sections delivered to site and laid end to end and connected together. 2. A track according to claim 1 characterised in that the sections are generally of channel shape including a base on which the rails are supported and a pair of upstands. 3. A track according to claim 2 characterised in that at least one of the upstands includes a hollow to accommodate services. 4. A track according to claim 3 characterised in that the hollow is closed by a cover. 5. A track according to any one of the preceding claims characterised in that pre-formed sections are adapted to support a sign, sensor and the like. 6. A track according to any one of the preceding claims characterised in that the pre-formed sections are adapted to support sound deflecting or sound absorbing or sound attenuating members which reduce sound emanating from the rail interface with the wheels of a railway vehicle. 7. A track according to any one of the preceding claims characterised in that the pre-formed sections are formed such that precipitation drains from the sections when laid. 8. A track according to claim 7 characterised in that the pre-formed sections, or at least some of the pre-formed sections are provided with drainage means which permit water to flow from the pavement. 9. A track according to any one of the preceding claims characterised in that the pre-formed sections include coupling means to facilitate their coupling to adjacent pre-formed sections. 10. A track according to any one of the preceding claims characterised in that each pre-formed section includes ballast. 11. A track according to claim 10 characterised in that means are provided to prevent the ballast spilling from the pre-formed section prior to the section being laid. 12. A track according to claim 11 characterised in that the means which prevent the ballast spilling from the pre-formed section comprises a temporary closure means which is removed when the section is laid. 13. A track according to any one of claims 10 to 12 characterised in that a membrane is provided between the material of the pre-formed sections and the ballast. 14. A track according to any one of the preceding claims characterised in that the pre-formed sections include support sleepers, or blocks, the sleepers or blocks having fixing means to which the rails may be secured. 15. A track according to claim 14 characterised in that each pre-formed section includes temporary alignment means secured to the sleepers or blocks and relative to the sections to retain the sleepers or blocks in a set position prior to laying of the pre-formed section on the foundation, which temporary alignment means are adapted to be removed prior to a rail being secured to the sleepers or blocks. 16. A track according to claim 15 characterised in that the alignment means includes lengths of service rail secured to the sleepers or blocks and relative to the sections. 17. A track according to any one of the preceding claims characterised in that the pre-formed sections are made of reinforced and/or pre-stressed concrete. 18. A track according to claim 17 characterised in that foundation includes ballast and there is provided between the foundation and the concrete pavement a membrane. 19. A method a providing a track for railway type vehicles on a base, characterised in that the method includes laying end to end a plurality of sections of track pavement on the base, the sections each being pre-formed, and connecting the sections together to provide a track pavement, and supporting a pair of rails by the track pavement. 20. A method according to claim 19 characterised in that the track has any of the features of the track according to any one of claims 1 to 18. 1. A pre-formed section for a track according to any one of claims 1 to 18.

Inventors: COPE DAVID, COPE, DAVID
Applicants: COPE DAVID, TARMAC UK LTD, COPE, DAVID, TARMAC HEAVY BUILDING MATERIALS UK LIMITED
Application year: 1999
Main classification: E01B3
IPC codes: E01B1, E01B3