GB2448500A

GB2448500A - Hollow railway sleeper

Info

Publication number: GB2448500A
Application number: GB0707353A
Authority: GB
Inventors: Robert Nicholas Blayney; Richard Alexander Grosvenor; David John Hindle; Charles Philip Richardson; Colin William John Rumble
Original assignee: SPECIALIST INNOVATIONS Ltd
Current assignee: SPECIALIST INNOVATIONS Ltd
Priority date: 2007-04-17
Filing date: 2007-04-17
Publication date: 2008-10-22
Also published as: GB0707353D0

Abstract

The sleeper comprises a body section having one or more hollow portions therein operable to be substantially filled by one or more filling materials, e.g. concrete. He sleeper has a filling hole 103, side bleed holes 104, internal wall portions 106 and grout filled reinforced sections 108 with rail chair fixing holes. The sleeper can support rail traffic for a short period before filling.

Description

Railway Sleeper The present invention relates to a railway sleeper, in

particular a replacement railway sleeper allowing for easier and safer replacement of existing railway sleepers a method of installing a railway sleeper and a railway sleeper assembly.

Historically, timber sleepers founded on and embedded in stone ballast and or concrete have supported railway track. This configuration relies on the quality and availability of the timber sleepers, which in recent years has diminished.

Where replacement of the sleepers is necessary, reinforced concrete sleepers have been the preferred solution.

However, this form of replacement poses both logistic and manual handling problems, as each sleeper weighs in excess of 105kg. For example, each sleeper may require a minimum of four men to lift and manoeuvre.

It is an object of the present invention to overcome the above or other problems associated with the prior art.

According to a first aspect of the present invention, there is provided a railway sleeper, the sleeper comprising a body section having one or more hollow portions therein, which hollow portions are operable to be substantially filled by one or more filling materials.

Advantageously, the railway sleeper may be positioned while in an unfilled configuration and subsequently substantially filled, in situ, thus the problematic weight

of prior art railway sleepers may be overcome.

For the avoidance of doubt, reference herein to an "unfilled configuration" refers to the railway sleeper having the hollow portions unfilled by one or more filling materials, whereas reference to a "filled configuration" refers to the railway sleeper having the hollow portions substantially filled by one or more filling materials.

Preferably, the sleeper is adapted to be fixable to a surface lo Preferably, the hollow portions account for at least 20% of the total volume of the body section. More preferably, the hollow portions account for at least 30% of the total volume of the body section. More preferably, the hollow portions account for at least 40% of the total volume of the body section. More preferably, the hollow portions account for at least 50% of the total volume of the body section. More preferably, the hollow portions account for at least 60% of the total volume of the body section. In a most preferred embodiment, the hollow portions account for at least about 75% of the total volume of the body sections.

Preferably, in an unfilled configuration, the railway sleeper weighs less than about 40kg, more preferably, less than about 35kg, more preferably, less than about 30kg. In a most preferred embodiment, in an unfilled configuration, the railway sleeper weighs less than about 25kg.

Advantageously, the railway sleeper weighs less than about 25kg in an unfilled configuration, thus facilitating easier handling and installation of the sleeper.

Preferably, the body section is formed from a composite material. Preferably, the body section is formed from glass phenolic resin compound.

Preferably, the railway sleeper comprises high stress areas and low stress areas. Preferably, the high stress areas are operable to withstand a greater load than the low stress areas. For example, preferably, the high stress areas are formed of thicker material than the low stress areas. Preferably, the high stress areas correspond to the points of the sleeper that directly carry a load, for example, where the wheel of a train passes thereover or where a rail is bolted thereto.

The high stress areas may comprise one or more re-enforced section.

In a preferred embodiment, the high stress areas are formed from about a 4 to 6 mm thick glass phenolic resin material, whereas, preferably, the low stress areas are formed from about a 2 to 4 mm thick glass phenolic resin material.

Preferably, the sleeper is adapted to allow one or more rails to be fixed thereto. Preferably, the sleeper comprises one or more captive internally threaded members, such as a captive nut, for example, operable to allow one or more rail to be fixed thereto.

The captive internally threaded member may be rendered captive in the railway sleeper by one or more adhesive compounds. In a preferred embodiment, the one or more adhesive compounds may comprise a blend of powdered and granular limestone. The captive internally threaded member may be situated in a high stress area.

Preferably, the railway sleeper is operable to withstand a load from a train while in the unfilled configuration, preferably, for at least 24 hours.

Preferably, the body section comprises an internal support matrix, which is preferably formed from a composite material. The internal support matrix may provide structural stability. The internal support matrix may be a three dimensional grid system, which may have an open pore structure.

The railway sleeper may be formed from a grid structure.

The railway sleeper may be formed from a mesh structure.

The railway sleeper may be formed from a cage structure.

Preferably, the railway sleeper may be formed from a cage structure having one or more internal walls, which internal walls may be formed from a solid mesh material.

Preferably, the one or more filling materials comprise a setting material, such as a cement material. Preferably, the one or more filling materials comprise dried aggregates.

According to a further aspect of the present invention there is provided a method of installing a railway sleeper comprising aligning a railway sleeper on a surface, the railway sleeper comprising a body section having one or more hollow portions therein, which hollow portions are operable to be substantially filled by one or more filling materials; and substantially filling the one or more hollow portions with one or more filling materials.

Preferably, the method comprises fixing the sleeper to a surface, which surface may be a track slab. The sleeper may be fixed to the surface using one or more adhesives such as grout, for example.

According to a further aspect of the present invention there is provided a railway sleeper assembly, the assembly comprising a railway sleeper fixed to a surface, the railway sleeper comprising a body section having one or more hollow portions, which hollow portions are substantially filled with one or more filling materials.

The assembly may further comprise one or more rail secured to the railway sleeper.

All of the features contained herein may be combined with any of the above aspects and in any combination.

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: Figure 1 shows a perspective view of an upper side of a railway sleeper in a filled configuration; Figure 2 shows a perspective view of a lower side of the railway sleeper in a filled configuration; Figure 3 shows a plan view of the railway sleeper in an unfilled configuration; Figure 4 shows a longitudinal sectional view of the railway sleeper in an unfilled configuration; Figures 4a, 4b and 4c show cross-sectional views through sections of the railway sleeper in an unfilled configuration; Figure 5 shows a plan view of the railway sleeper in a filled configuration; Figure 6 shows a longitudinal sectional view of the railway sleeper in a filled configuration; Figures 6a, 6b and 6c show cross-sectional views through sections of the railway sleeper a filled configuration; Referring to figure 1 there is shown a railway sleeper 102 having a generally cuboidal body. Apertures extend into an upper surface thereof, said apertures comprising a centrally disposed filling hole 103, operable to allow a filling material to enter the sleeper 102; side bleed holes 104, being in fluid communication with the filling hole 103 and operable to facilitate easy filling of internal hollow portions of the sleeper 102 (see below); and rail chair fixing holes 105 operable to enable a running rail to be bolted thereto, in use.

Figure 2 shows an underside of the sleeper 102. Normally the sleeper 102 lies upon and is embedded in railway ballast and/or concrete.

Figure 3 shows the sleeper 102 in an unfilled configuration. Toward a longitudinal centre of the sleeper 102 are two internal wall portions 106, each being formed from a glass phenolic resin mesh and extending through the sleeper generally perpendicular to a longitudinal axis thereof. Each panel is perforated by holes 107 to allow the free passage of one or more filling materials therethrough. Toward each longitudinal end of the sleeper 102 are two reinforced sections 108, each filled with a suitable filler such as a commercially available cementitious grout 109 and having rail chair fixing holes located therein. The reinforced sections 108 are spaced from the internal sidewalls of the sleeper 102 to allow the free passage of one or more filling materials therearound and are tapered towards the base of the sleeper 102.

Figure 4 shows the tapering of the four reinforced sections 108 and the disposition of the rail chair fixing holes 105 therein. Also shown is the filling hole 103 and the bleed holes 104 on the upper face of the sleeper 102 and the two internal wall portions 106 with their holes 107 operable to allow the passage of filling material therethrough.

Interspersed between the wall portions 106 and the reinforced sections 108 are several hollow portions each of which being operable, in use, to be substantially filled by one or more filling material as will be described hereunder in relation to Figures 5 & 6.

Figure 4a shows a cross sectional view through the internal wall portions 106 and shows the disposition of the holes 107.

Figures 4b and 4c show cross sectional views through the reinforced sections clearly showing that they each taper toward the sleeper base and the disposition of the rail chair fixing holes 105 within the reinforced sections 108 is also clearly shown.

Figures 5 and 6 show plan and cross longitudinal section views of the sleeper 102 in a filled configuration where the various compartments 110 (formerly hollow portions) between the internal walls 106 and reinforced sections 108, described above, have been infilled by the passage of filling material such as a suitable commercially available cementitious grout introduced through the filling hole 103 allowing air to bleed out through the bleed holes 104.

Figures 6a, 6b and 6c show the disposition of the filling material through the internal walls and around the reinforced sections of the sleeper.

In use, the sleeper 102 is normally positioned on a track slab (not shown) and fixed in place using a suitable commercially available adhesive grout, which is then allowed to set.

A rail (not shown) may then be secured by means of conventional chair fixings to the railway sleeper 102 by bolts into apertures 105. The number, size and positioning of these holes 105, together with the number size, configuration and positioning of the associated internal sleeper reinforced sections 108, will depend on the railway gauge, configuration and fixing arrangements of the running rails together with associated power conductor rails that may require fixing to the sleeper also. Either plastic or metal threaded inserts may be introduced into the holes 105 depending on the particular requirements of the railway.

The sleeper is then filled by introducing one or more filling materials into the filling hole 103. It will be appreciated that the sleeper 102 may be filled before or after one or more rails are secured thereto.

Advantageously, the provision of the reinforced sections 108 allows the sleeper to withstand a pressure before the hollow portions are substantially filled with one or more filling material. Therefore, in use, the sleeper 102 may be installed on a first shift (often, on railways, maintenance shifts occur overnight while the tracks are not in use) and the railway sleeper 102 can then be filled with the filling material on a subsequent shift, which may be 24hrs later, for example.

The filling material used to fill the hollow portions of the sleeper 102 via the filling hole 103 may be any suitable material, such as NATCEM 35, commercially available from Natural Cement Distribution Ltd. A sleeper 102 made in accordance with the present invention provides an alternative to known railway sleepers that is light and easy to handle, thus allowing a railway maintenance operator to lift and install the sleeper single handed, without the need to employ heavy lifting equipment. After installation, the railway sleeper may be used for short periods before being filled by the filling material. This avoids sections of railway being closed for extended periods while maintenance work is performed.

Also, although it has been generally described above that the sleepers of the present invention are suitable for use with underground railway networks, it will be appreciated by one skilled in the art, that the present invention may also be used in relation to any track bound vehicle that uses sleepers, for example, over ground trains.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features

disclosed in this specification (including any

accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1 A railway sleeper, the sleeper comprising a body section having one or more hollow portions therein, which hollow portions are operable to be substantially filled by one or more filling materials.

2 A railway sleeper according to claim 1, which is adapted to be fixable to a surface.

3 A railway sleeper according to claim 1 or 2, wherein the hollow portions account for at least 20% of the total volume of the body section.

4 A railway sleeper according to claim 3, wherein the hollow portions account for at least about 75% of the total volume of the body section.

5 A railway sleeper according to any preceding claim, wherein in an unfilled configuration, the railway sleeper weighs less than about 40 kg.

6 A railway sleeper according to any preceding claim, wherein the body section is formed from a composite material. * ** ** * * **

**

7 A railway sleeper according to any preceding claim, which comprises high stress areas and low stress * areas.

S *.* *

S..... * S S. S S* S **

8 A railway sleeper according to claim 7, wherein the high stress areas correspond to the points of the sleeper that directly carry a load.

9 A railway sleeper according to any preceding claim, which is adapted to allow one or more rails to be fixed thereto.

A railway sleeper according to any preceding claim, wherein the railway sleeper is operable to withstand a load from a train while in the unfilled configuration.

11 A railway sleeper according to any preceding claim, wherein the body section comprises an internal support matrix.

12 A railway sleeper according to any preceding claim, which is formed from a cage structure having one or more internal walls, which internal walls may be formed from a solid mesh material.

13 A railway sleeper according to any preceding claim, wherein the one or more filling materials comprise a setting material, such as a cement material.

14 A method of installing a railway sleeper comprising aligning a railway sleeper on a surface, the * S..

railway sleeper comprising a body section having *..* : 30 one or more hollow portions therein, which hollow portions are operable to be substantially filled by * one or more filling materials; and substantially *s.... * S S. S

S SS * **

filling the one or more hollow portions with one or more filling materials.

A method according to claim 14, which method further comprises fixing the sleeper to a surface, which surface may be a track slab.

16 A railway sleeper assembly, the assembly comprising a railway sleeper fixed to a surface, the railway sleeper comprising a body section having one or more hollow portions, which hollow portions are substantially filled with one or more filling materials.

17 A railway sleeper substantially as hereinbefore described and with reference to the accompanying drawings.

18 A method substantially as hereinbefore described and with reference to the accompanying drawings.

19 A railway sleeper assembly substantially as hereinbefore described and with reference to the accompanying drawings. * *I * * * * ** S* * * S... **.. S..

S * S ** I * S* * a.