Installing a slab for a slab track installation

Abstract

A mechanism for positioning, lifting or otherwise maneuvering a slab for a slab track. The slab is formed from fiber reinforced concrete. One or more clamps clamp over one or more sides of the slab. The slab is maneuvered using the clamp(s).

Description

[0001] INSTALLING A SLAB FOR A SLAB TRACK INSTALLATION

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to the field of railway infrastructure, and in particular to slab track installations.

[0004] BACKGROUND OF THE INVENTION

[0005] There is a long tradition of railway infrastructure that provides rails along which a rail-based vehicle, such as a tram or train, can be propelled.

[0006] In traditional railway infrastructure, rails are mounted upon railway sleepers or ties, which lie perpendicular to the direction of the track. Each railway sleeper provides two fixed locations to which the rail can be secured. The railways sleepers themselves are usually lain upon track ballast, typically formed of crushed stone (e.g., gravel), so that a load carried by the railway sleepers (e.g., of the tram / train) is distributed into the track ballast.

[0007] Another type of railway infrastructure is known as a “ballastless” or “slabtrack”, in which multiple railways sleepers are mounted on, or integrated in, a single (concrete) slab. Thus, a slab is able to couple to each rail at two or more different locations. This approach avoids the need for ballast, and provides advantages of improved performance capacity, reduction in maintenance cost / complexity and improve lifespan.

[0008] Conventional slabs for railway infrastructure (sometimes called “precast slabs”) have fixed positions to which the rails can be secured. Usually, these fixed positions are arranged to simulate a linear arrangement of railway sleepers, e.g. comprise two, parallel groups of linearly arranged fixed positions.

[0009] There is an ongoing desire to improve the speed and efficiency of installing a slab track installation.

[0010] SUMMARY OF THE INVENTION

[0011] The invention is defined by the claims.

[0012] According to examples in accordance with an aspect of the invention, there is provided a method for installing a slab for a slab track installation. The method comprises: obtaining the slab for mounting a rail, wherein the slab is formed from fiber reinforced concrete and comprises an upper surface for supporting the rail and a lower surface for engaging with a ground surface; positioning one or more clamps over one or more sides of the slab that connect the upper surface to the lower surface; after positioning each clamp, engaging each clamp with the upper and lower surface of the slab; and maneuvering the position of the slab using the one or more clamps.

[0013] The present disclosure advantageously recognizes that forming a slab, for mounting a rail, from fiber reinforced concrete (FRC) facilitates the use of a side-lifters to lift and reposition the slab with no or negligible risk of breaking or cracking of the slab. This advantageously avoids the need to use lifting bolts that connect to through-holes of the slab, allowing such through-holes to be omitted (for improved slab strength) and / or used for other purposes, such as supporting jacking bolts or the like.

[0014] Embodiments are particularly based on the realization that the strength afforded to the slab by the use of FRC allows a clamp-based lifting to take place with no / negligible risk of the slab breaking, unlike a slab formed of non-reinforced concrete.

[0015] Preferably, the slab is formed from ultrahigh performance fiber reinforced concrete (UHPFRC). This further reduces or minimizes any risk of the slab breaking or cracking during a lifting and / or maneuvering procedure.

[0016] In some examples, the step of maneuvering the position of the slab comprises positioning the slab at a desired location; and the method further comprises releasing the one or more clamps from the slab.

[0017] The slab may further comprise one or more apertures for receiving a respective one or more jacking bolts for levelling the slab, wherein the method further comprises positioning the one or more jacking bolts into the respective one or more apertures before releasing the one or more clamps from the slab. This approach advantageously allows the jacking bolts to be supported by, connected to or positioned in the slab before the slab is disengaged from the support. This avoids a need or requirement to use a secondary or supplementary support for the slab during installation of the slab.

[0018] In some examples, the step of positioning the one or more jacking bolts into the respective one or more apertures is performed before the step of maneuvering the position of the slab using the one or more clamps. This advantageously allows jacking to commence immediately (and directly) after the slab is maneuvered to a desired location. This increases an ease and efficiency installing the slab. The step of positioning the one or more jacking bolts into the respective one or more apertures may be performed before the step of positioning the one or more clamps over a side of the slab. This advantageously improves a speed of installing a slab track installation, as it allows the jacking bolt(s) to be installed whilst a lifting mechanism for the slab is otherwise occupied (e.g., maneuvering another slab). The efficiency of the overall installation process is thereby improved.

[0019] In some examples, the method further comprises, after positioning the slab at the desired location, levelling the slab using the one or more jacking bolts; and after levelling the slab using the one or more jacking bolts, performing the step of releasing the one or more clamps from the slab.

[0020] The step of maneuvering the position of the slab may comprise lifting the slab so as to be solely supported via the one or more clamps. This approach takes advantage of the recognition that forming the slab from FRC facilitates safe lifting of the slab using one or more clamps positioned over the side(s) of the slab.

[0021] The one or more clamps preferably comprise two or more clamps. This significantly reduces a stress on the slab during repositioning of the slab using the clamps, thereby improve a safety of lifting and reducing a risk of damaging the slab.

[0022] The step of positioning the one or more clamps may comprise: positioning a first set of one or more clamps over a first side of the slab; and positioning a second set of one or more clamps over a second side of the slab. This improves a distribution of stress on the slab during repositioning, thereby improving a safety of lifting and reducing a risk of damaging the slab.

[0023] Preferably, the first side is opposite the second side of the slab.

[0024] In some examples, the first set of one or more clamps comprises two or more clamps; and the second set of one or more clamps comprises two or more clamps. This further reduces a risk of stress on the slab causing the slab to fracture, crack or break during a lifting and / or maneuvering procedure using the clamps.

[0025] The upper surface of the slab may comprise one or more depressions and the step of positioning the one or more clamps may comprise positioning each clamp to engage with a depression in the upper surface.

[0026] The thickness of the slab may be no greater than 250mm, and preferably no greater than 200 mm. As previously explained, the use of FRC (and preferably UHPFRC) to form a slab facilitates the lifting of a slab from the sides. More particularly, the use of FRC facilitates the forming of a slab having a small thickness (e.g., <250mm or <200mm) that will not break or fracture when lifted from the side.

[0027] This approach advantageously allows the use of known and / or existing clampbased lifters, such as those used in the steel industry, for the lifting and / or repositioning of a slab.

[0028] The step of maneuvering the position of the slab using the one or more clamps may comprise: coupling each clamp to a same lifting mechanism of a crane; and operating the crane to maneuver the position of the slab.

[0029] There is also provided a method of installing a slab track installation comprising iteratively performing any herein disclosed method for each of a plurality of slabs.

[0030] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.

[0031] BRIEF DESCRIPTION OF THE DRAWINGS

[0032] For a better understanding of the invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0033] Figure 1 illustrates a slab for a slab track installation;

[0034] Figure 2 illustrates an existing approach for maneuvering the position of the slab;

[0035] Figure 3 is a flowchart illustrating a proposed method for maneuvering the position of the slab;

[0036] Figure 4 illustrates an example of the proposed approach for maneuvering the position of the slab;

[0037] Figure 5 is a flowchart illustrating further optional steps for installing the slab;

[0038] Figure 6 illustrates a variation of a slab for use in proposed methods; and Figure 7 illustrates a method for installing a slab track installation.

[0039] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] The invention will be described with reference to the Figures.

[0041] It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the apparatus, systems and methods, are intended for purposes of illustration only and are not intended to limit the scope of the invention. These and other features, aspects, and advantages of the apparatus, systems and methods of the present invention will become better understood from the following description, appended claims, and accompanying drawings. It should be understood that the Figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the Figures to indicate the same or similar parts.

[0042] The invention provides a mechanism for positioning, lifting or otherwise maneuvering a slab for a slab track. The slab is formed from fiber reinforced concrete. One or more clamps clamp over one or more sides of the slab. The slab is maneuvered using the clamp(s).

[0043] Figure 1 illustrates a slab 100 for a slab track installation. The slab is formed of concrete, and comprises an upper surface 101 for supporting or mounting a rail thereon and a lower surface 102 for engaging with a ground surface.

[0044] In practice, the slab 100 may comprise one or more rail engaging mechanisms or supports for supporting or mounting one or more rails. In particular, the slab 100 may comprise a plurality of rail engaging mechanisms or supports for supporting or mounting a plurality of rails. In particular, the slab 100 may comprise one or more sets (e.g., two or more sets) of rail engaging mechanisms, each set being configured for supporting or mounting a plurality of rails thereon. Preferably, for each rail, each set is configured for supporting or mounting at a different location of the rail

[0045] The rail engaging mechanism(s) or support(s) are not illustrated in Figure 1 for the sake of illustrative clarity. In the context of the present disclosure, a rail is a rail suitable for supporting a rail-based vehicle of railway infrastructure (and more particularly a rail-based vehicle for human transportation).

[0046] In order to produce the slab track installation, there is a need to install the slab 100 at a set (orthometric / normal / dynamic) height, position and angle / gradient of the slab with respect to a ground surface. This can ensure appropriate fitting and alignment of a rail. To achieve control over at least the height and angle / gradient of the slab, jacking bolts can be used to adjust the level and height of the slab. In particular acking bolts are used during a jacking procedure to level and / or define the height of the slab.

[0047] To facilitate this, the slab 100 comprises a plurality of apertures 111, 112, 113, 114 or through-holes, sometimes called jacking apertures. Each aperture is configured to receive a respective jacking bolt for levelling the slab when positioned on the ground surface. In particular, the aperture may comprise a threaded insert or interior surface that receives or engages with a geometrically corresponding jacking bolt (i.e., a geometrically corresponding rod or screw). The position of the jacking bolt in each respective aperture will define or control the angle of the slab with respect to the ground surface and the orthometric height of the slab. The position of the jacking bolt within the aperture may be controllable by rotating the jacking bolt with respect to the threaded insert or interior surface of the aperture.

[0048] The (threaded) aperture(s) may (each) be positioned towards a side edge of the upper surface of the slab, e.g., no further than 20cm away from a side edge of the upper surface of the slab.

[0049] To perform a jacking procedure, after the slab is positioned on a ground surface, the position of the jacking bolt(s) within each aperture will be adjusted by an installer of the slab until the slab is level (e.g., flat or horizontal) and at a desired (orthometric / normal / dynamic) height. A material, such as cementitious grout, may then be poured beneath the slab and allowed to set or solidify, to thereby provide a level slab on a ground surface. The jacking bolts may be removed or left behind.

[0050] The slab 100 may further comprise one or more further apertures 121, 122. These further apertures are designed for permitting the passage of a fluid and settable material, such as cementitious grout, therethrough. This increases an ease of pouring such material beneath the slab during a jacking procedure.

[0051] It is recognized that there is a need to position or maneuver the slab to a desired location for installation.

[0052] Figure 2 illustrates an existing approach for positioning or maneuvering the slab 100 to a desired location.

[0053] In this existing approach, the apertures 111, 112, 113, 114, which are each designed to receive a jacking bolt, are repurposed to receive a lifting bolt or shackle 211, 212, 213, 214. Each receiving lifting bolt or shackle may protrude from the upper surface 101 of the slab 100. Each lifting bolt or shackle is then connected to a lifting mechanism (not illustrated), e.g., of a crane, via a respective connector - such as a cable or chain. The lifting mechanism is then able to lift and maneuver the slab via the lifting bolts or shackles connected to the slab.

[0054] Thus, the lifting bolts or shackles connect to the same threaded insert or surface that is used by the jacking bolts. This requires that the lifting bolts are first bolted into or engaged with the slab, the slab is then lifted into the desired location and lowered down on to a temporary support system (e.g., wooden batons). The lifting bolts are then disengaged or unbolted from the slab to then allow the jacking bolts to be bolted into or engaged with the same apertures (previously used by the lifting bolts) through the slab to allow levelling and positioning of the slab to height. This jacking procedure then allows the removal of the temporary support system.

[0055] It has been recognized that the existing procedure provides slow and inefficient production of the slab track installation. In particular, because the same apertures are used for performing two separate functions or procedures, significant time is taken in removing the lifting bolts to insert or engage the jacking bolts. This significantly affects a speed of installing the slab track installation.

[0056] It has previously been considered essential for a slab for a slab track installation to be formed from a thick (e.g., > 250 mm) block of concrete to provide the necessary support for the rail-based vehicle. This has previously necessitated the use of the lifting bolt technique to ensure safe lifting of the slab with negligible risk (e.g., of cracking, breaking or damage) during the lifting and / or other maneuvering of the slab.

[0057] The present disclosure provides an alternative approach to maneuvering or installing the slab.

[0058] In particular, it has been recognized that if a slab for a slab track installation is formed from fiber reinforced concrete, then the performance properties of the fiber reinforced concrete facilitate side-lifting of the slab whilst still providing sufficient support for a railbased vehicle. Thus, it has been recognized that side-lifting of a slab (e.g., using side-lifters such as those traditionally used for steel) is facilitated through the use of a slab formed from fiber reinforced concrete (FRC). A slab formed from normal concrete (which is configured for use as a slab of a rail track installation) lifted in this way would not have the structural performance to enable a safe lift. In particular, a fiber reinforced concrete provides suitable elastic flexural strength to facilitate side-lifting.

[0059] This capability is particularly pronounced, or more easily facilitated, if the slab is formed from ultrahigh performance fiber reinforced concrete (UHPFRC).

[0060] UHPFRC has a standardized ruleset, e.g., as set out in the French standards NF P 18-470 “Concrete - Ultra-High Performance Fibre-Reinforced Concrete - Specifications, Performance, Production And Conformity” and NF P 18-710, “National Addition to Eurocode 2 — Design of Concrete Structures: Specific Rules for Ultra-High Performance Fiber- Reinforced Concrete (UHPFRC)”. Another example standard for UHPFRC is set out by the Swiss Standard SIA 2052 UHPFRC.

[0061] Another mechanism for defining an ultrahigh performance fiber reinforced concrete is to define a UHPFRC as a fiber reinforced concrete that meets an ultrahigh performance concrete (UHPC) standard, such as the ASTM Cl 856 testing standard. The skilled person would therefore readily understand the meaning and scope of the term UHPFRC.

[0062] Figure 3 illustrates a method 300 for maneuvering a slab for a slab track installation that exploits this recognition. The method 300 may be incorporated as a part of a more general method for installing the slab.

[0063] The method 300 comprises a step 310 of obtaining the slab for mounting a rail. As previously explained, the slab is formed from fiber reinforced concrete, and preferably from UHPFRC. The slab comprises an upper surface for supporting the rail and a lower surface for engaging with a ground surface.

[0064] The method 300 also comprises a step 320 of positioning one or more clamps over one or more sides of the slab that connect the upper surface to the lower surface.

[0065] In a preferred example, step 320 comprises positioning a first set of one or more clamps over a first side of the slab; and positioning a second set of one or more clamps over a second side of the slab. This will significantly reduce any localized stress of the slab when lifted or otherwise maneuvered. Preferably, the first side is opposite the second side of the slab. This further reduces any localized stress of the slab when lifted or otherwise maneuvered.

[0066] In yet more preferred examples, the first set of one or more clamps comprises two or more clamps; and the second set of one or more clamps comprises two or more clamps. This also reduces any localized stress of the slab when lifted or otherwise maneuvered.

[0067] The method 300 also comprise a step 330 of, after positioning each clamp, engaging each clamp with the upper and lower surface of the slab.

[0068] The method 300 also comprises a step 340 of maneuvering the position of the slab using the one or more clamps. Step 340 may, for instance, comprise positioning the slab at a desired location. In particular, step 340 may comprise lifting, moving and then lowering the slab.

[0069] The one or more clamps may be connected to a lifting mechanism, e.g., of a crane, which is used to maneuver or reposition the slab. Thus, as an example, step 340 may comprise coupling each clamp to a same lifting mechanism of a crane; and operating the crane to maneuver the position of the slab.

[0070] In particular examples, step 340 may comprise lifting the slab so as to be solely supported via the one or more clamps. This is facilitated through the use of FRC, and preferably UHPFRC, as the material forming the slab.

[0071] The proposed method allows the jacking bolts to be pre-engaged with the slab before the slab is maneuvered to a desired location. This significantly reduces an installation time for the slab, as there is no need to engage the jacking bolts after maneuvering to the desired position.

[0072] Suitable examples for the structure of slabs that can be maneuvered using the proposed approach are set out in the UK Patent Application having publication number GB 2,602,688 A, which discloses embodiments in which the slab is formed of FRC and / or UHPFRC.

[0073] Thus, the slab may comprise two or more primary transverse grooves; and a plurality of rail supports, each rail support being mounted in a respective primary transverse groove and comprising at least one projection configured to engage with a rail fastening system, received in the respective primary transverse groove, that couples a rail to the rail support so as to restrict or prevent a movement of the rail in a direction perpendicular to the direction of the respective primary transverse groove. Other variants will be apparent to the skilled person.

[0074] Preferably, the thickness of the slab is no greater than 250mm, and preferably no greater than 200 mm. This facilitates the use of existing clamps and lifting mechanisms, improving an adaptability of the proposed method with existing techniques. Such embodiments also exploit the recognition that the use of FRC (and preferably UHPFRC) to form a slab facilitate the provision of a strong slab (i.e., having good flexural strength), having a relatively small thickness, that can be safely lifted using side-lifters (i.e., clamps that clamp at a side), i.e., without cracking or breaking.

[0075] Figure 4 illustrates a proposed approach for positioning or maneuvering a slab 400 to a desired location. Figure 4 therefore illustrates a suitable slab for use in proposed methods and embodiments.

[0076] The slab 400 is formed of fiber reinforced concrete (FRC), and is preferably formed of ultrahigh performance fiber reinforced concrete (UHPFRC).

[0077] The slab again comprises an upper surface 401 for supporting or mounting a rail thereon and a lower surface 402 for engaging with a ground surface. A distance between the upper and lower surfaces defines a thickness of the slab. Sides 404, 405 connect the upper surface 401 of the slab to the lower surface 402 of the slab. A distance between the sides 404, 405 defines the width of the slab. A distance along the slab in a direction perpendicular to the width of the slab defines the length of the slab.

[0078] In practice, the slab 400 may comprise one or more rail engaging mechanisms or supports for supporting or mounting the rail (and / or other track elements, such as switches). Examples have been previously described. These are not illustrated in Figure 4 for the sake of illustrative clarity.

[0079] In the illustrated example, a plurality of clamps 411, 412, 413, 414 are positioned over (i.e., to partially cover) one or more sides 404, 405 of the slab 400. In the illustrated example, at least one clamp is positioned over each of a pair of opposing sides 404, 405 of the slab 400. The clamps then engage with the upper 401 and lower surfaces 402 of the slab, such that each clamp clamps the slab 400 therebetween (e.g., squeezes the clamp between jaws of the clamp).

[0080] More specifically, in the illustrated example, a first set of clamps 411, 412 is positioned over a first side 404 of the slab and a second set of clamps 413, 414 is positioned over a second side 405 of the slab 400. The first and second set of clamps are aligned with one another, such that a clamp from one set faces a clamp from another set. This improves an evenness of the lifting and / or maneuvering of the slab 400.

[0081] Although preferred for reduced risk of localized stresses, it is not essential that the first set of clamps and the second set of clamps comprises a plurality of clamps. Rather, each set may comprise only a single clamp. Thus, there may be provided a first set of one or more clamps and a second set of one or more clamps.

[0082] Although preferred for improved evenness of lifting, it is not essential that the first set of (one or more) clamps and the second set of (one or more) clamps comprise the same number of clamps.

[0083] Although preferred for improved maneuverability, safety and reduced localized stress, it is not essential to make use of a plurality of clamps. Some embodiments may make use of a single clamp, or set of clamps, that clamps over a single side of the slab 400. Thus, one of the first and second sets of one or more clamps may be omitted in some variants.

[0084] Suitable examples of clamps for engaging with the slab will be readily apparent to the skilled person. In particular, existing clamps (such as those used to maneuver steel (beams)) can be repurposed for use in maneuvering the slab 400 for a slab track installation.

[0085] In some examples, each clamp used in transporting or maneuvering the slab may comprise a pair of opposing jaws that can open and close with respect to one another. In some examples, the maximum movable distance between the pair of opposing jaws (of each clamp) may be no greater than 300 mm, e.g., no greater than 250 mm. This allows existing clamps (such as those used for transporting steel (beams)) to be repurposed for use in a proposed railway installation scheme or method. The position of the slab 400 can be maneuvered using the clamp(s). Thus, each clamp may be connected to a lifting mechanism, such as that of a crane, via one or more connectors (e.g., one or more chains or cables). Appropriate connectors for lifting a slab will be apparent to the appropriately skilled person, e.g., steel cables. In some examples, each clamp is connected to a lifting frame (not illustrated in Figure 4). The lifting frame helps to define or control the position of each clamp, e.g., to ensure appropriate distribution or spread of the clamp(s).

[0086] Figure 4 also illustrates how the proposed approach facilitates the insertion or engagement of the jacking bolt(s) 431, 432, 433, 434 (in)to the slab before the clamp(s) are disengaged from the slab. This advantageously facilitates improved speed of installing the slab as part of a slab track installation.

[0087] The jacking bolt(s) are used to perform the jacking procedure, which is similar or identical to the procedure previously described, e.g., to level the slab or define a height of the slab.

[0088] For the sake of completeness, Figure 4 also illustrates how the slab may comprise one or more further apertures designed for permitting the passage of a fluid and settable material, such as cementitious grout, therethrough. This increases an ease of pouring such material beneath the slab during or after a jacking procedure.

[0089] Figure 5 illustrates a method 500 for installing a slab for a slab track installation. The method 500 comprises the method 300 for maneuvering a slab for a slab track installation, which has been previously described.

[0090] The method 500 further comprises a step 510 of releasing the one or more clamps from the slab. More particularly, step 510 may be performed only after the slab has been moved (in step 340) to a desired location for installing the slab.

[0091] The method 500 may further comprise a step 520 of positioning the one or more jacking bolts into the respective one or more apertures before releasing the one or more clamps from the slab, i.e., before performing step 510. Of course, to facilitate the performance of step 520, the slab further comprises one or more apertures for receiving a respective one or more jacking bolts for levelling the slab.

[0092] Step 520 may, for instance, comprise positioning the jacking bolt(s) in the aperture(s) such that each jacking bolt extends out or protrudes out of the lower surface of the slab by no less than a predetermined amount, e.g., no less than 20mm, e.g., no less than 40mm. This allows the jacking bolt(s) to support the weight of the slab when the slab is positioned on the ground surface. One advantage of step 520 is that the jacking bolt(s) can be supported by the slab before the slab is disengaged from the clamp(s). This avoids or reduces a reliance upon a temporary support system for the slab whilst installing the jacking bolt(s), as previously required for previous slab positioning techniques when switching from using one or more lifting bolts to one or more jacking bolts.

[0093] Step 520 may be performed at any time after the step 310 of obtaining the slab, as conceptually illustrated by dashed lines. The precise timing of step 520 may, for instance, depend upon the availability of manpower, the location to which the slab is to be positioned and so on.

[0094] In preferable examples, the step of positioning the one or more jacking bolts into the respective one or more apertures is performed before the step of maneuvering the position of the slab using the one or more clamps. This means that the jacking bolt(s) can be appropriately positioned before the slab is maneuvered. This can advantageously allow the jacking procedure to begin immediately after the slab is maneuvered to a desired location, increasing an ease and efficiency of performing the jacking procedure and overall installation of the slab.

[0095] In preferred examples, the step of positioning the one or more jacking bolts into the respective one or more apertures is performed before the step of positioning the one or more clamps over a side of the slab. This advantageously improves a speed of installing a slab track installation, as it allows the jacking bolt(s) to be installed whilst a lifting mechanism for the slab is otherwise occupied (e.g., maneuvering another slab). The efficiency of the overall installation process is thereby improved.

[0096] In some alternative approaches, step 520 can be omitted if the slab obtained in step 310 is accompanied with the one or more jacking bolts positioned therein. This approach is less preferred, as it increases a difficulty of transporting the slab (accompanied with the jacking bolts), as it reduces a stacking efficiency of the slab(s).

[0097] The method 500 may further comprise a step 530 of, after positioning the slab at the desired location (i.e., performing step 340), levelling the slab using the one or more jacking bolts. Thus, step 530 is effectively the performance of the jacking procedure previously described. Approaches for levelling a slab using one or more jacking bolts have been previously disclosed.

[0098] After or during the levelling the slab using the one or more jacking bolts, the step 510 of releasing the one or more clamps from the slab is performed. Thus, step 530 may be performed or started between step 340 and step 510. More specifically, step 510 may be performed once the weight of the slab is longer supported by (only) the clamps. More particularly, step 510 may be performed once the weight of the slab is supported by the jacking bolt(s) during the performance of step 530.

[0099] Figure 6 illustrates a variant to the slab 400.

[0100] Once again, it is noted that the slab 400 may comprise one or more rail engaging mechanisms or supports for supporting or mounting the rail. Examples of these have been previously described. These are not illustrated in Figure 6 for the sake of illustrative clarity.

[0101] The slab 400 further comprises one or more depressions 611, 612, 613, 614, here: a plurality of depressions, in the upper surface 401 of the slab 400. Each depression 611, 612, 613, 614 may be designed for receiving a clamp therein. This can help with guiding the clamp(s) to an appropriate location for supporting the slab 400 and / or reduce the risk of she clamp(s) sliding, e.g., during or after clamping of the slab. Accordingly, the step of positioning the one or more clamps may comprise positioning each clamp to engage with a depression in the upper surface.

[0102] For the sake of illustrative understanding, the position of a single clamp 413 within a depression 613 is illustrated in Figure 6. In practice, each of a plurality of clamps may be positioned in each depression, or more than one clamp may be positioned in a same depression.

[0103] In the illustrated example, each depression 611, 612, 613, 614 is formed as a groove that extends inwardly from a side of the slab. Thus, the depression is at least partially exposed at a side of the slab. This approach advantageously allows the depression(s) to be repurposed during mounting or installation of a rail to the slab. In particular, each depression can be used to aid in the welding of a rail mounted to the slab, as it can provide a gap beneath the rail for maneuvering a welder to an underside of the rail. Put another way, depressions that are designed for ease of welding a rail mounted to the slab can be repurposed for receiving a clamp for maneuvering of the slab.

[0104] When the slab takes the structure of a slab disclosed by UK Patent Application having publication number GB 2,602,688, then each depression 611, 612, 613, 614 may function as a secondary transverse groove of such a slab - as defined in this UK Patent Application.

[0105] Figure 7 illustrates a method 700 for installing a slab track installation.

[0106] The method 700 comprises iteratively performing any previously described method for each of a plurality of slabs. The method 700 may, in some examples, further comprise a step 710 of mounting a rail to each slab. This can create a trackform for the slab track installation. Approaches for mounting a rail to a slab are known in the art, such as the approach disclosed by UK Patent Application having publication number GB 2,602,688.

[0107] A method for installing a rail support arrangement comprising a slab is disclosed by the International Patent Application having International Patent Application No. WO 2022 / 153049 Al. The proposed approach for maneuvering a slab could be readily integrated into such a technique to improve a speed and efficiency of installing the rail support arrangement. The slab disclosed in this document is an example of a slab suitable for being used with the proposed method.

[0108] The bounds constraints on the dimensions and / or physical properties of the slab may be delimited by at least three factors, namely: logistical constraints (e.g., defining a maximum size and / weight for transportation); loading capacity of the clamp(s); and / or the flexural strength of the slab.

[0109] Using conventional transportation systems with current technological constraints, a reasonable maximum width for a slab is 4.5m (e.g., a maximum width of 4m) and a maximum length of around 20m, e.g., around 18m. The skilled person will appreciate that appropriate maximum dimensions for the slab will vary dependent upon technology development s) and any jurisdictional restrictions for the slab.

[0110] In some examples, the thickness of the slab is no greater than 250 mm, and preferably no greater than 200 mm. This advantageously facilitates the use of “off-the-shelf’ clamps for maneuvering the slab.

[0111] In some examples, the thickness of the slab is no less than 50 mm, e.g., no less than 70 mm. This helps provide sufficient flexural strength for maneuvering the slab using side-connecting clamps.

[0112] In preferred examples, the slab is formed of a material (fiber-reinforced concrete) that has an elastic flexural strength of no less than 7 MPa. This advantageously provides a slab having good flexural strength for maneuvering with negligible risk of cracking or other breaking.

[0113] As a working example, appropriate dimensional and / or property bounds for a slab are to define the slab as having: a minimum flexural strength of 7 MPa, a width of no more than 4.5m (e.g., no more than 4m), a thickness of no less than 70mm, a thickness of no more than 250mm (e.g., no more than 200mm) and a length of no more than 20m, e.g., no more than 18m. Remaining within these constraints facilitates the provision of a slab that can be safely maneuvered, with minimal or negligible risk of cracking or breaking. In other words, these restrictions set out appropriate bounds for ensuring a safe slab that can be maneuvered appropriately. It is emphasized that these are only working examples, and that slabs of different sizes may also be provided. Of course, proposed slabs do not need to have properties and / or dimensions that are at these extreme limits. As an example, a slab having a width of 4m and a length of 18m may be useful for turnouts, but less useful for defining a slab for a straight section of track. Rather, a slab having a width of 3m and a length of 10m may be suitable for defining a straight section of track.

[0114] Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0115] The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. If the term "adapted to" is used in the claims or description, it is noted the term "adapted to" is intended to be equivalent to the term "configured to". Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1. A method for installing a slab for a slab track installation, the method comprising: obtaining the slab for mounting a rail, wherein the slab is formed from fiber reinforced concrete and comprises an upper surface for supporting the rail and a lower surface for engaging with a ground surface; positioning one or more clamps over one or more sides of the slab that connect the upper surface to the lower surface; after positioning each clamp, engaging each clamp with the upper and lower surface of the slab; and maneuvering the position of the slab using the one or more clamps.

2. The method of claim 1, wherein the slab is formed from ultrahigh performance fiber reinforced concrete.

3. The method of claim 1 or 2, wherein: the step of maneuvering the position of the slab comprises positioning the slab at a desired location; and the method further comprises releasing the one or more clamps from the slab.

4. The method of claim 3, wherein the slab further comprises one or more apertures for receiving a respective one or more jacking bolts for levelling the slab, wherein the method further comprises positioning the one or more jacking bolts into the respective one or more apertures before releasing the one or more clamps from the slab.

5. The method of claim 4, wherein the step of positioning the one or more jacking bolts into the respective one or more apertures is performed before the step of maneuvering the position of the slab using the one or more clamps.

6. The method of claim 5, wherein the step of positioning the one or more jacking bolts into the respective one or more apertures is performed before the step of positioning the one or more clamps over a side of the slab.

7. The method of any of claims 4 to 6, further comprising: after positioning the slab at the desired location, levelling the slab using the one or more jacking bolts; and after levelling the slab using the one or more jacking bolts, performing the step of releasing the one or more clamps from the slab.

8. The method of any of claims 1 to 7, wherein the step of maneuvering the position of the slab comprises lifting the slab so as to be solely supported via the one or more clamps.

9. The method of any of claims 1 to 8, wherein the one or more clamps comprises two or more clamps.

10. The method of claim 9, wherein the step of positioning the one or more clamps comprises: positioning a first set of one or more clamps over a first side of the slab; and positioning a second set of one or more clamps over a second side of the slab.

11. The method of claim 10, wherein the first side is opposite the second side of the slab.

12. The method of claim 10 or 11, wherein: the first set of one or more clamps comprises two or more clamps; and the second set of one or more clamps comprises two or more clamps.

13. The method of any of claims 1 to 12, wherein the upper surface of the slab comprises one or more depressions and the step of positioning the one or more clamps comprises positioning each clamp to engage with a depression in the upper surface.

14. The method of any of claims 1 to 13, wherein the thickness of the slab is no greater than 250mm, and preferably no greater than 200 mm.

15. The method of any of claims 1 to 14, wherein the step of maneuvering the position of the slab using the one or more clamps comprises: coupling each clamp to a same lifting mechanism of a crane; and operating the crane to maneuver the position of the slab.

16. A method of installing a slab track installation comprising iteratively performing the method of any of claims 1 to 15 for each of a plurality of slabs.

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