GB2506894A

GB2506894A - Railway structure mounting system and method

Info

Publication number: GB2506894A
Application number: GB1218253.1A
Authority: GB
Inventors: Nicholas James Marshall
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-10-11
Filing date: 2012-10-11
Publication date: 2014-04-16
Also published as: GB201218253D0; WO2014057281A1; EP2917411A1; GB201507983D0; GB2521981A

Abstract

A method of securing an ancillary railway structure 2 on a slope 4 that slopes downwards away from a railway track assembly 6, the method comprising; supporting the structure on the slope in an installed position and anchoring the structure to the railway track assembly via a tensioned link bearing 24. The link bears a tensile load applied by the structure. Ancillary railway structures, links and kits for installation in accordance with the method are also disclosed. The ancillary railway structure is provided with a support 20. The support may comprise a vertical member 36 and a foot 38. The link bearing may comprise a first fixing for attachment to the ancillary railway structure and a second fixing (52, fig. 6E) for attachment to the railway track assembly and wherein the first and second fixings are co operable with a connector for connecting the fixings.

Description

Improvements relating to railway structures

Field of the invention

This invention relates to ancillary railway structures and methods, apparatus and kits for installing and securing such structures on slopes adjacent to railway track assemblies.

Background to the invention

Railway track assemblies generally have ancillary railway structures in their vicinity. Such structures may, for example, be any structures that assist in the maintenance of the railway track assembly or simply play some part in railway operations.

Numerous systems are known for installing ancillary railway structures in the vicinity of railway track assemblies. For example, it is known from US6443363B to attach a support device to a railway track assembly via a cantilevered service member. Given its cantilevered nature, the service member can bear only a light load. For heavier ancillary railway structures, a strut or the like providing ground support is necessary, as is envisaged in one embodiment.

US2012032128A teaches supports for attaching a temporary safety fence to a railway track assembly, which supports rest on the railway track assembly bed. The supports are attached to a web of a rail with magnets and therefore also appear suitable only for bearing a light load.

Particular difficulties with regard to ancillary railway structures, especially heavier structures requiring a ground support, arise in the context of slopes adjacent to railway track assemblies. Such slopes may be natural or engineered (i.e. embankments or cuttings).

In Great Britain (GB) and elsewhere, a substantial portion of the rail network is built on embankments. The purpose of embankments is generally to maintain a broadly constant elevation or shallow gradient through undulating terrain; or to raise track assemblies to avoid other infrastructure (e.g. suburban road networks).

Embankments are commonly formed from low-grade bulk material such as slag or fuel ash and they tend to deteriorate over time due to vibration, settlement, decomposition and damage from water, vegetation and burrowing animals.

The Network Rail Civil Engineering Policy Justification (2010) indicates that embankments account for approximately 44% of the GB rail network (4,885 of the 11,194 route miles), that their average age is approximately 150 years, that of total earthworks (embankments, cuttings, retaining walls and culverts) only 49% are judged to be in serviceable condition, and that climate change is resulting in an increased frequency of extreme weather events which are the trigger for the majority of earthwork failures.

The upward trend in failures and deterioration coincides with the need for increased output to meet rising demand. The McNulty Review (May 2011) indicated the potential fora 100% increase in both passenger and freight demand in GB by 2030.

Tn July 2012 the British government published a High Level Output Statement (HLOS) requiring Network Rail to plan for increases of 16% in passenger demand and 23% in freight demand during the period 2015-2019. The resulting plans will include new and reinstated lines, however the bulk of the additional output will be achieved by increased utilisation of the existing routes, coupled with a programme of upgrades and enhancements such as: electrification to accommodate heavier, longer and faster trains; and upgrades to signalling, power and communications (SPC) for increased train paths (frequencies).

Electrification and SPC projects entail the installation of further ancillary railway structures, including cabling, alongside the tracks and typically these are located on the shoulder of embankments or other slopes. Consequently these structures, often including enclosures, impose an additional load on the embankment and are vulnerable to stress and displacement when the embankment deteriorates.

Embankments must also accommodate walking routes and "positions of safety" which are required for inspection and maintenance. These ancillary railway structures are subject to specific standards and they are normally located in the "ce" alongside the track, which is vulnerable to displacement and where space is often limited or inadequate.

Where the width of the cess is insufficient, specific positions or places of safety can be provided, normally in the form of marked "reflges". The maximum permitted distance along a railway line to reach these is 25 metres so the maximum spacing is 50 metres.

Most conventional arrangements for installing ancillary railway structures are unsuitable for slopes or embankments given the risks of subsidence and displacement. Accordingly, ancillary railway structures, such as for example secure refuges and equipment cabinets, are typically installed on embankments by specialist methods including piles, foundations, and slope stabilisation or retention works. These methods generally entail significant time and cost, with the need for closure ("possession') of the adjacent track for the use of rail-mounted plant.

It is an object of the invention to provide ancillary railway structures that exert a reduced load on embankments or other slopes adjacent to railway track assemblies, as well as methods and apparatus for installing and securing such structures.

Statements of the invention

According to a first aspect of the invention, there is provided a method of securing an ancillary railway structure on a slope that slopes downwards away from a railway track assembly, the method comprising: supporting the structure on the slope in an installed position; and anchoring the structure to the railway track assembly via a tensioned link, the link bearing a tensile load applied by the structure. Suitably, the slope may be a railway embankment.

The inventor has appreciated that that the loading required for the attachment of ancillary structures, such as for example refuges and equipment cabinets, is minimal compared to the load-bearing capacity of railway track assemblies. Current railway track assemblies are designed to support fully loaded trains, e.g. 350 tonnes for an Intercity 125' and 1800 tonnes for a freight train. The load is distributed due to the integrated and continuously welded nature of track assemblies. The track assembly itself has a typical weight of approximately 500kg per metre.

In accordance with the method of the invention, an ancillary railway structure may use the track assembly as an anchorage, reducing the load supported on the embankment or other slope. Importantly, by anchoring the ancillary railway structure via a tensioned link, a substantial load can be applied to the railway track assembly, which load thus need not be borne by the slope. Exposure to subsidence of the slope is thus reduced and the longevity of the slope enhanced.

Due to the beneficial effect of its tensioned link, the method may be particularly useful in securing heavy ancillary railway structures, e.g. ancillary railway structures for bearing one or more persons. However, the ancillary railway structure may in principle be any structure or component of any weight desired to be installed on a slope adjacent to a railway track assembly. For example, the ancillary railway structure may comprise one or more of a refuge, a platform, a path or walkway, a lookout post or shelter, a cabinet, a mast, post or pole, a lamp, sign or signal, a duct, pipe, trough or enclosure, a cable or service, a photo-voltaic array or power generation device, a handrail, barrier, fence or guard, a sound insulation barrier or device, a fall-arrest device, a membrane, grid or mesh, equipment, plant or machinery, signalling, power or communications equipment, power generation or transmission equipment, track monitoring equipment, train or rolling stock monitoring equipment, slope or geotechnical monitoring equipment, sound insulation equipment, fall-arrest, or access or safety equipment.

In one embodiment, the method comprises resting the structure on the slope in the installed position and anchoring the structure to the railway track assembly to resist a sliding movement of the structure down the slope. This advantageously eliminates the need for fixing the structure to the slope itself, which might cause erosion or subsidence. The method may however also embrace fixing the structure to the slope, particularly in a manner that forestalls or mitigates subsidence. Thus, in another embodiment, the method comprises fixing the structure on an unstable slope in the installed position and anchoring the structure to the railway track assembly to resist a subsiding movement of the structure.

The tensile load in the link may arise through sliding, subsidence or the like but may preferably be applied initially, upon securing the structure. For example, the method may comprise supporting the structure in the installed position at a fulcrum located on the slope at a first lateral distance from the railway track assembly, such that the centre of gravity of the structure is at a second lateral distance from the railway track assembly, the second lateral distance being greater than the first lateral distance. The fulcrum may comprise one or more supports.

In an embodiment of the invention, anchoring the structure may comprise linking the structure and the track assembly such that at least a component of the tensile load borne by the link is exerted on the railway track assembly in a lateral direction (with reference to longitudinal extension of the track assembly). Optionally such lateral loads may be balanced by securing ancillary structures on both sides of a railway track assembly in accordance with any of the methods described herein.

The structure may be anchored to the railway track assembly in any suitable manner consistent with ensuring that the link bears a tensile load and exerts this on the railway track assembly. In one embodiment of the invention, the structure is anchored to the railway track assembly such that the link exerts a shear force on at least a component of the railway track assembly.

S

As aforesaid, a particular benefit of the invention is that it can enable anchoring of significant loads to the railway track assembly via the tensioned link. The tensile load borne by the link may, for example, be at least 50 kg or even at least 100 kg or at least 250 kg. The tensile load borne may be inefficient, if not impossible, to bear by a link under compression, bending or shear load. Therefore, the structure may advantageously be anchored such that at least a section of the link (or even the entire link) is free from compression, bending and shear load.

The structure may be supported on the slope such that it exerts a compressive load on the slope. In an embodiment, the structure may then be anchored to the track assembly such that the compressive load exerted on the slope is reduced by at least 25%, preferably at least SO°/o relative to the unanchored structure. The total weight of the ancillary structure and/or any applied load may, for example, be at least 100 kg or even at least 500 kg or at least 1000 kg and the compressive load may be substantially reduced accordingly.

In embodiments of the invention, the method comprises anchoring the structure to one or more of the following railway track assembly components: a sleeper; a running rail; a running rail fixing. The structure may be anchored with the help of any suitable fixings, for example a bolt, a cavity fixing, a chemical anchor or a captive hook. In an embodiment, the method comprises inserting a fixing of the link into a fixing hole of the railway track assembly.

Additionally or alternatively, a bracket of the link may be attached to the railway track assembly to anchor the structure. In an embodiment, the bracket may be attached to the railway track assembly without altering the stwcture of the railway track assembly and/or with no more than two bolts or other fixings. This reduces the time and complexity of installation and the potential for requiring possession of the railway track assembly. In an embodiment, the method may comprise locating the bracket on a sleeper of the railway track assembly to engage a running rail of the railway track assembly.

Whilst in some embodiments of the invention the structure may be anchored by a single link, for additional strength and/or stability, the method may preferably comprise anchoring the structure to the railway track assembly via a plurality of tensioned links, e.g. at least two, or at least three, or at least four links.

According to a second aspect of the invention, there is provided an ancillary railway structure for installation on a slope adjacent to a railway track assembly, the structure comprising: a support for supporting the structure, in an installed position, on a slope that slopes downwards away from a railway track assembly; and a link for connecting the structure to the railway track assembly and bearing a tensile load exerted by the structure in the installed position.

Advantageously, the structure may be installed on a slope that slopes downwards away from a railway track assembly extending in a generally longitudinal direction. In embodiments, the stwcture may be installed in accordance with any suitable method described herein.

The support may take any suitable form. In one embodiment of the invention, the support comprises a vertical member and an inclined foot, or indeed a plurality of vertical members with inclined feet. However, the support may in principle be any suitable part of the structure.

According to a third aspect of the invention, there is provided a link for bearing a tensile load exerted on a railway track assembly by an ancillary railway structure installed on a slope adjacent to the railway track assembly, the link comprising a first fixing for attachment to the ancillary railway structure and a second fixing for attachment to the railway track assembly, the first and second fixings being co-operable with a connector for connecting the fixings. The link may be suitable for bearing a tensile load of at least 50 kg or even at least 100 kg or at least 250 kg or at least 500 kg. The first and/or second fixings may be integral with the connector.

The link according to the third aspect of the invention may of course be employed in the method and structure of the first and second aspects of the invention.

In principle, a link as recited in any of the aspects of the invention may take any form consistent with its function. In one embodiment, the link comprises a fixing for engaging a fixing hole of the railway track assembly.

Additionally or alternatively, the link may comprise a fixing in the form of a bracket for attachment to the railway track assembly. In an embodiment, the bracket comprises a frame having a base and first and second arms extending from the base, the first and second arms being spaced apart for accommodating a sleeper of a railway track assembly. The frame may advantageously comprise a shoulder for engaging a running rail of the railway track assembly.

Preferably, the bracket may further comprise a cross-member for linking free ends of the first and second arms of the frame to secure the frame to an accommodated sleeper. This stwcture presents a particularly convenient and effective fixing for attaching the link to the railway track assembly, being both strong and rapid to install. The cross-member may comprise a fixing hole for receiving a connecting member of the link, e.g. a hook or bolt.

The link, and its connector if present, may comprise a plurality of elements. In some embodiments the link/connector may comprise a rigid connecting member such as a steel bar and/or a flexible connecting section, such as a cable. Advantageously, the link/connector may comprise vibration damping and/or electrical insulation means to isolate the ancillary railway structure from the railway track assembly.

The invention also embraces, according to a fourth aspect, a kit for anchoring an ancillary railway structure on a slope adjacent to a railway track assembly, the kit comprising: a link according to the third aspect of the invention; and instructions for installing the link between an ancillary railway structure and a railway track assembly such that the structure is anchored to the railway track assembly via the link and the link bears a tensile load applied by the structure. The instructions may, for example, be for carrying out any of the methods described hereinabove. They may be provided together with the link or in a designated separate document, such as a manual or webpage.

Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of the words, for example "comprising" and "comprises", mean "including but not limited to", and do not exclude other components, integers or steps.

Moreover the singular encompasses the plural unless the context otherwise requires: in particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Preferred features of each aspect of the invention may be as described in connection with any of the other aspects. Other features of the invention will become apparent from the following examples. Generally speaking the invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims and drawings). Thus features, integers, or characteristics described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. Moreover unless stated otherwise, any feature disclosed herein may be replaced by an alternative feature serving the same or a similar purpose.

Where upper and lower limits are quoted for a property, then a range of values defined by a combination of any of the upper limits with any of the lower limits may also be implied.

Specific description

Embodiments of the present invention will now be further described with reference to the accompanying figures, of which: Figure 1A shows a schematic cmss-section of an ancillary railway structure according to a first embodiment of the invention secured on an embankment; Figure lB shows a schematic plan view of the ancillary railway structure of Figure 1A; Figure 2 shows a perspective view of the ancillary railway structure of Figures 1A and IB; Figure 3 shows a perspective view of an ancillary railway structure according to a second embodiment of the invention secured on an embankment; Figure 4 shows a perspective view of a frame and a cross member of a bracket of the ancillary railway structure of Figure 3; Figure 5A shows a side view of the frame of Figure 4 in an installed position on a railway track assembly; Figure 5B shows a side view of the cross member of Figure 4 in an installed position on a railway track assembly; Figure 5C shows a partial side view of a bracket of the ancillary railway structure of Figure 3 installed position on a railway track assembly; Figure 5D shows a partial plan view of a bracket of the ancillary railway structure of Figure 3 installed position on a railway track assembly; Figures 6A to 6E show plan views of fixing point variants for attaching an anchor link of an ancillary railway structure to a railway track assembly; Figures 7A to 7G show schematic sectional views of variants of anchor links attaching an ancillary railway structure to a railway track assembly; and Figures BA to SD show schematic sectional views of variants of vertical supports supporting an ancillary railway structure attached to a railway track assembly with anchor links.

Referring to Figures 1A, lB and 2 in a first embodiment of the invention a refuge 2 is secured on a railway embankment slope 4 that slopes downwards away from a railway track assembly 6 extending in a generally longitudinal direction and bounded by a cess 8. The railway track assembly 6 is of conventional type, comprising first and second longitudinal running rails 10 that are attached to a plurality of sleepers 12 via rail shoes 14 and rail clips 16 (shown only in Figure 2).

The refuge 2 is an ancillary railway structure that provides a place of safety next to the railway track assembly 6. The refuge 2 comprises a platform 18, first and second pairs of vertical supports 20, a bridge 22 and first and second anchor links 24. The weight of the refuge is approximately 250 kg and it typically supports one to four people.

The platform 18 of the refuge 2 is generally oblong in plan, comprising a horizontal steel mesh 26 bounded on three of its sides by a safety barrier 28 extending upwards. At a fourth boundary of the steel mesh 26, the platform is connected via a hinge 30 to the bridge 22, which comprises a further oblong steel mesh 32 of smaller dimension.

The horizontal steel mesh 26 of the platform is mounted on a frame 34 to which the safety barrier 28 and the first and second pairs of vertical steel supports 20 are attached near corners of the frame 34. Each support 20 extends downward from its point of attachment and comprises a generally vertical member 36 and a foot or bearer plate 38. The first pair of the supports 20 is attached to the corners adjacent the open boundary of the steel mesh 26 of the platform 18. The second pair of supports 20 is attached at the remaining opposite corners of the frame 34.

The lengths of the vertical members 36 of the supports 20 are adjustable by a screw jack mechanism 40. The angle of each foot or bearer plate 38 with respect to its associated vertical member 36 is also adjustable.

Referring now specifically to Figure 1A, the platform 18 and bridge 22 of the refuge 2 are supported by the supports 20, which have been suitably adjusted, on the embankment 4 next to the cess 8 and the railway track assembly 6, such that the platform 18 is substantially horizontal and the bridge 22 extends between the platform 18 and the cess 8 bounding the railway track assembly 6. In this position the refuge 2 exerts a compressive load on the slope 4.

Referring now also to Figure 2, the first and second anchor links 24 secure (or anchor) the refuge 2 in the installed position. Each anchor link 24 comprises a bar of steel 42 connected at one end to the bridge 22 of the refUge 2 via a bolt (not shown) and at the other end to the railway track assembly 6. Specifically, the first and second anchor links 24 are each connected to a sleeper 12 of the railway track assembly 6. In this embodiment the sleepers 12 are of the steel type, comprising a fixing hole 44 at lateral ends, and the first and second anchors are attached to their respective sleepers by a bolt (not shown) inserted into these holes 44.

The first and second anchor links 24 bear a tensile load as they anchor the refuge 2 to the railway track assembly 6. The tensile load can be applied upon installation of the refuge 2 by adjustment of the supports 20, particularly a shortening of the second pair of supports 20. In such an adjustment, the first pair of supports acts as a fulcrum. The tensile load may also be increased by a load applied to the platform 18, subsidence of the slope 4 on which the refuge is supported, or by sliding movement of the refuge 2 down the slope 4. The tensile load borne by the anchors 24 reduces the compressive load exerted by the refuge 2 on the slope 4.

A component of the tensile load of the first and second anchors 24 is exerted on the sleepers 12 of the track assembly in a generally lateral direction. In this manner, the refuge 2 is anchored to the track assembly 6, with a significant portion of the weight of the refuge 2 being borne by the track assembly 6 rather than by the supports 20 resting on the slope 4.

Exposure to subsidence of the slope 4 is thus reduced and the longevity of the slope 4 enhanced.

The first embodiment may be readily modified. For example, it will be appreciated that the manner in which the anchor links 24 are attached to the railway track assembly 6 may vary, for example to accommodate other sleeper materials or designs.

Referring now to Figure 3, in a second embodiment of the invention a refuge 50 is secured on an embankment 4 that slopes downwards away from a railway track assembly extending in a generally longitudinal direction and bounded by a cess 8. The reftige 50 of the second embodiment is identical to that of the first embodiment of the invention, and is also secured identically to the railway track assembly 6, save that the first and second anchor links 24 are attached to respective concrete sleepers 12 with the help of respective brackets 52. Like reference numerals are used for like parts in Figure 3.

Both brackets 52 are identical in structure. With reference to Figures 4 and 5A to SD each bracket 52 comprises a frame 54 and a cross-member 56.

Referring still to Figure 4, the frame comprises a web of steel 58 which has been bent at first and second corners 60 to be generally U-shaped in plan, with a distal base 62 joining first and second arms 64, 66 having proximal free ends 68, 70. The distance between the first and second arms 64, 66 is slightly greater than the width of a concrete railway sleeper (not shown in Figure 4). The frame 54 comprises an upper side 72, at which a boundary of the web 58 defines a first, lower shoulder 74 and a second, higher shoulder 76 in each of the arms 64, 66. The higher shoulders 76 are located more distally than the lower shoulders 74. The shoulders 74, 76 of the first arm 64 are identical and aligned with the shoulders 74, 76 of the second arm 66. Towards their free ends 68, 70, the arms 64, 66 each comprise a bolt hole 78. The bolt holes 78 of the arms 64, 66 are also aligned.

With continued reference to Figure 4, the cross-member 56 comprises a web of steel 80 that has been bent to define an upper panel 82, a central panel 84, a lower panel 86 and first and second lateral panels 88, 90, all of which are integral. Each of the panels 82, 84, 86, 88, 90 is oblong in shape. The upper panel 82 and the lower panel 86 are parallel to each other, extending perpendicularly from upper and lower boundaries of the central panel 84 in distal and proximal directions respectively. The lateral panels 88, 90 are parallel to each other and extend perpendicularly in the proximal direction from first and second lateral boundaries of the central panel 84, with the width defined by these panels 88, 90 corresponding to that of a concrete railway sleeper. Thus the central panel 84 connects all the remaining panels 82, 86, 88,90 and is orthogonal to each of them. The lower panel 86 comprises a fixing hole 92 and each of the lateral panels comprises a bolt hole 94.

With reference to Figures 3, 4, 5A and SB, the frame 54 and cross-member 56 of the bracket 52 are shaped for attachment to a conventional railway track assembly 6 comprising concrete sleepers 12, rail shoes 14, rail clips 16 and two running rails 10. To attach a bracket 52 to the railway track assembly 6, the frame 54 is slid onto a sleeper 12 between the running rails 10, with the upper side 72 of the frame 54 comprising the shoulders 74, 76 facing upwards and the arms 64, 66 of the frame 54 extending outwards towards an end 96 of the sleeper 12.

Referring now specifically to Figure 5A, the first, higher shoulders 76 of the arms 64, 66 of the frame 54 are made to abut a rail foot of the running rail 10 of the railway track assembly 6, such that (further) movement of the frame 54 towards the end 96 of the sleeper 12 is prevented. In this installed position of the frame 54 the free ends 68, 70 of the arms 64, 66 of the frame 54 project beyond the end 96 of the sleeper 12 such that their bolt holes 78 are accessibly clear.

The cross-member 56 serves to affix the frame 54 in its installed position and to provide a fixing hole 92 for the anchor links 24. Referring to Figures 3 and SB, the cross-member 56 is brought into an installed position at the end 96 of the sleeper 12 by resting the upper panel 82 of the cross-member 56 on an upper surface of the sleeper 12. Tn this position, the bolt holes 94 of the lateral panels 88,90 of the cross-member 56 align with the accessibly clear bolt holes 78 of the arms 64, 66 of the frame 54, such that the frame 54 and the cross member 56 can be connected by first and second bolts 98 to bring the bracket 52 as a whole into an installed and secured configuration, illustrated in Figures SC and SD.

Referring still to Figures SC and SD, the secured bracket 52 provides, in the lower panel 86 of the cross-member 56, the fixing hole 92, which is suitable for receiving a captive hook 100 (or alternatively a bolt or other fixing) of an associated anchor link 24, such that the anchor link 24 can be securely affixed to the railway track assembly 6. In this manner, the bracket 52 enables a significant tensile load borne by the anchor links 24 (exerted by the refuge 2 as a whole) to be applied to the railway track assembly 6, specifically the running rail 10 and sleeper 12.

The bracket 52 used in the second embodiment of the invention represents a particularly advantageous fixing means for providing a strong connection of the anchor links 24 to a sleeper 12 that does not itself comprise any fixing holes. On account of its construction, the bracket 52 can be rapidly and securely installed on a railway track assembly 6, helping to avoid the need for long and disruptive possession of track. Notably, installation of the bracket 52 does not require any modification to the structure of the railway track assembly itself. The bracket 52 can be installed by quick connection of only two main parts (the frame 54 and the cross-member 56) with first and second bolts 98. The installed bracket exerts a (lateral) shear force on running rail 10.

Despite the particular advantages of the bracket 52, it will be appreciated that the anchor links 24 may also be connected to the railway track assembly in other ways. The first and second embodiments may be readily modified accordingly. Figures 6A to GE illustrate schematically a range of variants for attaching an anchor link 24 to a railway track assembly, with Figure 6B representing the arrangement of the first embodiment and Figure 6E representing the second embodiment. In other variants, the links 24 are attached to a running rail 10 of the track assembly 6 as shown in Figure 6A, for example by a clamping device or any other suitable alternative fixing (not shown). Likewise, such a fixing may be applied to a rail shoe 14 or rail clip 16 as shown in Figure 6D. Alternatively, a bracket 101, for example of the type used in the second embodiment, may extend around and abut against one or more rail shoes 14 or rail clips 16 as shown in Figure 6C. All these variants ensure that the tensile load borne by the link is exerted on the railway track 6 assembly (at least partly) in a lateral direction orthogonal to the longitudinal extension of the track.

In further variants, the refUge 2 may of course be modified or replaced to comprise any other desired ancillary railway structure. It may comprise, or be secured with, only a single anchor link 24 or more than two anchor links 24. With reference to Figures 7A to 7G, the length and nature of the anchor links 24 may also be modified. In variants of the exemplary embodiments described hereinabove, the anchor links 24 are substantially horizontal as shown in Figure 7A, upwardly inclined as shown in Figure 7B, formed to rest on the cess of a railway track as shown in Figure 7C, or formed to rest on a slope as shown in Figure 7D. With reference to Figures 7E and 7F, in fUrther variants, the anchor links 24 comprise a section that is installed underground and/or a section that is clear of the ground. Referring to Figure 7G, in another variant, the anchor links 24 comprise a flexible section of composite material or cable and conform to a slope. In all these variants the anchor link is essentially free from compression, bending and shear load. In further variants, the anchor link includes vibration damping or electrical insulation means. Such means may, for example, be provided between a bracket of the link and the railway track assembly.

Referring now to Figures 8A to 3D, the vertical supports 20 of the refuge 2 or other ancillary structure may also be modified or replaced by alternative supports. With reference to Figures 8A and 8B, in variants, the refuge or other ancillary railway structure 2 is supported by a screw pile 102 that affixes it to the slope. Referring to Figure 8A, in one variant the screw pile 102 is substantially vertical. With reference to Figure 8B, in another variant the screw pile 102 is substantially perpendicular to the slope. The vertical supports 20 may also be done away with such that a suitably inclined lower surface 104 of the refuge 2 or other ancillary railway stncture rests either directly on the slope 4 or on a bearer plate 106 installed on the slope, as illustrated in Figures 8C and 8D respectively.

The refuge 2 or other ancillary railway structure, or indeed just one or more anchor links, may be supplied as an uninstalled kit with suitable instructions for installation.

Of course many further modifications will be apparent to those skilled in the art without departing from the scope of the invention.

Claims

Claims 1. A method of securing an ancillary railway structure on a slope that slopes downwards away from a railway track assembly, the method comprising: supporting the structure on the slope in an installed position; and anchoring the structure to the railway track assembly via a tensioned link, the link bearing a tensile load applied by the structure.
2. The method of claim 1, comprising resting the structure on the slope in the installed position and anchoring the structure to the railway track assembly to resist a sliding movement of the structure down the slope.
3. The method of claim 1, comprising fixing the structure on an unstable slope in the installed position and anchoring the structure to the railway track assembly to resist a subsiding movement of the structure.
4. The method of any preceding claim, comprising supporting the structure in the is installed position at a fulcrum located on the slope at a first lateral distance from the railway track assembly, such that the centre of gravity of the structure is at a second lateral distance from the railway track assembly, the second lateral distance being greater than the first lateral distance.
5. The method of any preceding claim, wherein anchoring the structure comprises linking the structure and the track assembly such that at least a component of the tensile load borne by the link is exerted on the railway track assembly in a lateral direction orthogonal to a longitudinal direction of the railway track.
6. The method of any preceding claim, wherein the structure is anchored to the railway track assembly such that the link exerts a shear force on at least a component of the railway track assembly.
7. The method of any preceding claim, wherein the structure is anchored such that at least a section of the link is free from compression, bending and shear load.
8. The method of any preceding claim, wherein the structure is supported on the slope such that it exerts a compressive load on the slope and wherein the structure is anchored to the track assembly such that the compressive load exerted on the slope is reduced by at least 25% relative to the unanchored structure.
9. The method of any preceding claim comprising anchoring the structure to one or more of the following railway track assembly components: a sleeper; a running rail; a running rail fixing.
10. The method of any preceding claim comprising inserting a fixing of the link into a fixing hole of the railway track assembly.
11. The method of any preceding claim comprising attaching a bracket of the link to the railway track assembly.
12. The method of claim 11, comprising attaching the bracket to the railway track assembly without altering the structure of the railway track assembly.
13. The method of claim 11 or claim 12 comprising locating the bracket on a sleeper of the railway track assembly to engage a running rail of the railway track assembly.
14. The method of any preceding claim comprising anchoring the structure to the railway track assembly via a plurality of tensioned links.
15. An ancillary railway structure for installation on a slope adjacent to a railway track assembly, the structure comprising: a support for supporting the structure, in an installed position, on a slope that slopes downwards away from a railway track assembly; and a link for connecting the structure to the railway track assembly and bearing a tensile load exerted by the structure in the installed position.
16. The structure according to claim 15, wherein the structure is installed on a slope that slopes downwards away from a railway track assembly, the track assembly extending in a generally longitudinal direction.
17. The structure of claim 15 or claim 16 wherein the support comprises a vertical member and an inclined foot.
18. A link for bearing, and exerting on a railway track assembly, a tensile load applied by an ancillary railway structure installed on a slope adjacent to the railway track assembly, the link comprising a first fixing for attachment to the ancillary railway structure and a second fixing for attachment to the railway track assembly, the first and second fixings being co-operable with a connector for connecting the fixings.
19. The method, structure or link of any preceding claim, wherein the link is arranged to bear a tensile load of at least 100 kg.
20. The method, structure or link of any preceding claim, wherein the link comprises a fixing for engaging a fixing hole of the railway track assembly.
21. The method, structure or link of any preceding claim, wherein the link comprises a bracket for attachment to the railway track assembly.
22. The method, structure or link of claim 21, wherein the bracket comprises a frame having a base and first and second arms extending from the base, the first and second arms being spaced apart for accommodating a sleeper of a railway track assembly.
23. The method, structure or link of claim 22, wherein the frame comprises a shoulder for engaging a running rail of the railway track assembly.
24. The method, structure or link of claim 22 or claim 23 wherein the bracket further comprises a cross-member for linking the free ends of the first and second arms of the frame to secure the frame to the accommodated sleeper.
25. The method, structure or link of claim 24, wherein the cross-member compris a fixing hole for receiving a connecting member of the link.
26. The method, structure or link of any preceding claim, wherein the link comprises a plurality of elements.
27. The method, structure or link of any preceding claim, wherein the link comprises a rigid connecting member.
28. The method, structure or link of any preceding claim, wherein the link comprises a flexible connecting section.
29. The method, structure or link of any preceding claim, wherein the link comprises vibration damping and/or electrical insulation means.
30. A kit for anchoring an ancillary railway structure on a slope adjacent to a railway track assembly, the kit comprising: a link as claimed in any one of claims 18 to 29; and instructions for installing the link between an ancillary railway structure and a S railway track assembly such that the structure is anchored to the railway track assembly via the link and the link bears a tensile load applied by the structure.
31. A method of securing an ancillary railway structure on a slope that slopes downwards away from a railway track assembly substantially as described herein with reference to the accompanying drawings.
32. An ancillary railway structure for installation on a slope adjacent to a railway track assembly substantially as described herein with reference to the accompanying drawings.
33. A link for bearing, and exerting on a railway track assembly, a tensile load applied by an ancillary railway structure substantially as described herein with reference to the accompanying drawings.