GB2547283A

GB2547283A - Device for splicing reinforcement cages

Info

Publication number: GB2547283A
Application number: GB1602668.4A
Authority: GB
Inventors: Render Stephen
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-02-15
Filing date: 2016-02-15
Publication date: 2017-08-16
Anticipated expiration: 2036-02-15
Also published as: GB2547283B; GB201602668D0

Abstract

A device 50a, 50b for splicing two reinforcement cages. The first cage comprises a suspension band adjacent one longitudinal end and the second cage carries the device adjacent one longitudinal end. The device comprises a first anchoring portion 112 attached to the second cage adjacent said one end, a second anchoring portion 114 connected to the first anchoring portion and transversely spaced therefrom to define a transverse suspension gap G between the anchoring portions, and a suspension member 120 attachable to the anchoring portions so as to bridge the suspension gap, with the suspension band of the first cage located in the suspension gap. The suspension member comprises an elongate hollow body, which may be a cylindrical steel coupler. The hollow suspension member provides a stronger and stiffer anchoring connection than a solid bolt of comparable mass per unit length. The cages may be of the pile or diaphragm wall type. The suspension member is attached to the first and second anchoring portions by means of a female-male screw threaded connection and an abutment recess or notch seating, respectively. The anchoring portions may be spaced by a bridging portion 116 to define a U-shaped yoke.

Description

DEVICE FOR SPLICING REINFORCEMENT CAGES

TECHNICAL FIELD

This invention relates to a device for splicing reinforcement cages, including pile cages and diaphragm wall cages. It also relates to a combination of at least two reinforcement cages spliced using one or more of the devices. The invention further relates to a method for splicing reinforcement cages using one or more of the devices, and to piles, diaphragm walls and other structures formed using reinforcement cages spliced according to the said method.

BACKGROUND OF THE INVENTION AND PRIOR ART

Reinforcement cages such as pile cages are used in a wide range of civil engineering and construction applications, principally in the formation of concrete piles in the construction of buildings, underground car parks, roadway or rail or other bridges, and other structures. Pile cages not only provide reinforcement for the concrete of the pile, but they also provide a means of attaching or anchoring part(s) of the building, bridge or other structure to the built pile itself.

As used herein, the term “pile cage” means a generally cylindrical or other cross-sectional shaped assembly or network of a plurality, typically at least about 4, 5 or 6, or possibly more than six, of (usually) metallic, e.g. steel, cage bars extending in a generally longitudinal direction (defined as a direction parallel to the axis of the pile to be formed around the cage) and anchored together or interconnected by one or more frame elements, e.g. a wire or some other alternatively configured frame arrangement, which maintains the relative positioning, separation and alignment of the cage bars. Thus a pile cage is a relatively stiff, structurally relatively stable assembly, and is often manufactured off-site in a dedicated assembly plant and transported by vehicle to the building site ready for use in the building of the required piles.

Typically a hole of the required size and cross-sectional shape to form the pile is formed in the ground by drilling and is then at least partially lined with a re-usable casing in order to prevent wall collapse. A pile cage is then lowered into the lined hole and wet concrete is then poured therein, embedding the cage within it. The casing is then, while the concrete is still wet, withdrawn for re-use and the concrete is then allowed to cure to form the pile.

Frequently, however, it is necessary to form particularly tall piles, i.e. of a height greater than the length of a single individual pile cage. In this case it is common practice to have to splice together at least two pile cages end-to-end, i.e. to connect the top end of a lower pile cage to the bottom end of an upper pile cage. Frequently as many as three, four or even more individual pile cage sections are spliced together end-to-end in a corresponding manner to form a single unified pile cage of the required total length. The complete pile cage assembly is typically built up incrementally as the individual cage sections are spliced together and lowered in a stagewise manner into the lined hole. During the splicing and stagewise lowering operation each successive pile cage section is generally accurately positioned, e.g. using a crane, directly above an exposed upper portion of the pile cage section below it, then spliced thereto by whatever means is being employed for that job.

In the formation of concrete structures other than circular piles, reinforcement cages of other types or configurations may be used. For example, diaphragm walls, such as those of rectangular, or even L-shaped or T-shaped, cross-section may be formed in an analogous manner to piles, but instead of using a pile cage as such, a reinforcement cage of an appropriate alternative shape and configuration is used. Such an alternative form of reinforcement cage used to form diaphragm walls may thus be termed a “diaphragm wall cage”. However, its principles of construction, function and use are substantially the same or closely analogous to that of pile cages as described above, as is well known to persons skilled in the art.

Splicing together pairs of reinforcement cages, whether of the pile, diaphragm wall or other type, is however not a simple matter, and the job comes with ever increasing health and safety risks that have to addressed. Various methods and devices for splicing together reinforcement cages are therefore known, and in recent years these have not only been aimed at simplifying the mechanical job of uniting adjacent reinforcement cage lengths, but also to do so with greater attention paid to health and safety risks, such as the need to avoid workers having to place their hands or arms inside the interior space within a part-assembled reinforcement cage during a splicing operation.

One such well-known and currently commercially widely used system for splicing together adjacent pile cages is disclosed in published International Patent Application W02007/068898 (also published as EP1963579A). Here a supported lower pile cage is fitted with a circumferential suspension band, e.g. by welding to the longitudinal cage bars, and the upper pile cage is fitted with at least one support plate (preferably a plurality, e.g. three, thereof, equi-angularly spaced) such as by welding thereof to a respective cage bar.

Each support plate has a screw-threaded aperture therein, into which is screwable from outside the cage a respective suspension bolt. Once the upper pile cage has been lowered (e.g. by a crane) and accurately positioned above the lower pile cage with the support plates on the upper pile cage positioned adjacent the suspension band on the lower pile cage and the axis of the threaded apertures in the support plates located below the suspension band, the suspension bolts are inserted into their respective threaded apertures in the respective support plates so as to protrude radially inwardly of the pile cages (i.e. transverse to the longitudinal axes of the pile cages and directed generally towards those axes) and beneath the suspension band on the lower pile cage. Once screwed home, the suspension bolts thus collectively abut the underside of the suspension band and so serve to carry the lower pile cage beneath the upper pile cage as the latter is lifted or craned into a new position, such as a new location on site or to be lowered into a hole lining casing ready for pouring of concrete to form a pile around the combined pile cages.

In an alternative configuration to the above, the support plates may instead be provided on the lower pile cage and the suspension band on the upper pile cage. In this case, in the step of lowering and positioning the upper pile cage above the lower pile cage, the axis of the threaded apertures in the support plates is located above the suspension band, so that once the suspension bolts have been inserted into their respective apertures in the respective support plates and screwed home, the suspension bolts thus collectively abut the topside of the suspension band. In this manner the suspension band (on the upper pile cage) still serves to carry the lower pile cage beneath the upper pile cage as the latter is lifted or craned into a new position, it simply being that the support plates and the suspension band have been inverted in their relative positioning on the respective upper and lower pile cages.

It has been found in practice that this known pile cage splicing system has several disadvantages:

These known radially-inwardly extending suspension bolts are anchored and supported substantially only at their radially outer ends, i.e. in the respective support plates only. This “encastre” cantilevering means that in the event that load is placed on a bolt at a point a distance “x” away from its cantilevered anchoring in its respective support plate, then any deflection suffered by the bolt at that loading point is proportional to “x3”. Thus, any loads applied to the bolts at increasing radial distances from their respective anchoring points in the respective support plates can give rise to especially large lateral bolt deflections. This can be critical for suspension bolts of a given diameter and/or strength, since even modest loadings on such bolts at increasing distances from their respective support plates can cause moderate or even excessive bending of the bolts, or even their breaking altogether. Such mechanical failure of at least some of the suspension bolts means that they can no longer be expected to properly support and carry the suspension band of the lower pile cage, which as a result may all too easily slide off at least some of the suspension bolts or even the entire collective support provided by the complete array of bolts. At worst the lower pile cage may even fall off it completely, the suspension band having slid off the bolts entirely, and become separated from the pile cage assembly. Clearly this can lead to highly risky working conditions for site workers and may have highly serious consequences for health and safety.

This application of loading forces, especially eccentric loading forces, on the suspension bolts at increasing distances from their respective anchoring locations on the support plates may be commonly encountered in any instance where a given pile cage is free to move laterally (i.e. transversely relative to the longitudinal direction of the pile cage) with respect to an adjacent pile cage. Such freedom of movement may occur for example where a pile cage has been damaged, e.g. bent, in transit or in storage, possibly as a result of mishandling or lack of supervision. In the case of pile cages which incorporate spacers that are used to centralise adjacent pile cages with respect to one another and/or within a casing, it may also result from damage or flattening to such spacers. It may also result from asymmetrical misalignments in the relative configurations of the cage bars of adjacent pile cages where one is “cranked” with respect to the other, i.e. the cage bars of one cage in an end region thereof are configured so as to be bent to lie a short distance radially inwardly of the main body of the other cage, in order to improve the flow of liquid concrete into the cage when poured therein and also to assist in the alignment of one pile cage with respect to the next.

Moreover, the exertion of an excessive bending load on one suspension bolt only can easily lead to overloading of other bolts at other circumferential locations around the cage, possibly leading to progressive failure of all the bolts. It is thus a potentially particularly serious shortcoming of this known system of splicing pile cages that relies on cantilevered suspension bolts to perform a stable and reliable cage suspending function.

Corresponding problems can occur in the use of known reinforcement cages of other types, including diaphragm wall cages, which are constructed and utilised in an analogous manner and using corresponding principles to pile cages.

It might be natural to think that these problems could be ameliorated by using longer and/or thicker or stronger suspension bolts. However in practice this is not a good solution. For one thing, it would require the use of heavier and bulkier components and equipment, which not only increases cost, but also makes manual fixing and screwing home of the suspension bolts more difficult and time consuming, which may be especially troublesome in the case of congested cages where small circumferential gaps between cage bars may not allow the insertion of thicker bolts. For another thing, it does not address the fundamental problems arising from overloading and excessive bending of even such longer and/or stronger bolts as a result of loading points increasingly spaced from their “encastre” cantilevered fixings in the respective support plates, which can still occur for the practical reasons discussed above. Furthermore, the use of longer bolts would generally be undesirable anyway, since they would hinder the placement into the interior of the spliced cages, once they are in position in the relevant hole in the ground, of the circular concreting tube (“tremmie”) used to fill the hole with wet concrete during the pouring stage of the pile- or wall-forming operation.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to at least partially solve or ameliorate at least some of the above problems associated with prior art reinforcement cage splicing systems, in particular the pile cage splicing system of W02007/068898 (EP19663579A), by providing a reinforcement cage splicing device that does not rely on merely cantilevered suspension bolts.

Accordingly, in a first aspect the present invention provides a device for splicing a first reinforcement cage to a second reinforcement cage, wherein the first reinforcement cage comprises a suspension band adjacent one longitudinal end thereof and the second reinforcement cage carries the said device adjacent one longitudinal end thereof, the device comprising: a first anchoring portion attached to the second reinforcement cage adjacent said one end thereof; a second anchoring portion connected to the first anchoring portion and transversely spaced therefrom to define a transverse suspension gap between the first and second anchoring portions; and a suspension member anchorable or anchored to the first and second anchoring portions so as to bridge said suspension gap with the suspension band of the first reinforcement cage located in said suspension gap, wherein the suspension member comprises an elongate hollow body.

As used herein, the terms “anchorable”, “anchored” and “anchoring” (and equivalent terms) are to be construed broadly as meaning that the suspension member is able to be located, arranged or configured, or is located, arranged or configured, relative to the respective anchoring portions such that the suspension member is substantially fixed or immovable relative thereto at least in a direction corresponding to, or generally substantially parallel to, a longitudinal direction of the first and second reinforcement cages in which loading force acts when the reinforcement cages are spliced together and suspended. Thus, as used herein, it is within the scope of the terms “anchorable”, “anchored” and “anchoring”, etc that the suspension member, once so located, arranged or configured relative to the respective anchoring portions, may exhibit one or more degrees of freedom of movement (e.g. translational or rotational) relative to one or more of the anchoring portions, other than in the aforementioned direction corresponding to, or generally substantially parallel to, a longitudinal direction of the first and second reinforcement cages in which loading force acts when the reinforcement cages are spliced together and suspended.

Also as used herein, the term “adjacent” referring to the respective locations at which the suspension band and the device of the invention are provided relative to the respective longitudinal ends of the respective first and second reinforcement cages, is to be construed broadly as meaning “adjacent, or approximately or somewhat adjacent, or near or in the vicinity of” the respective longitudinal ends of the respective cages, and is not to be interpreted narrowly as meaning strictly at or immediately adjacent the respective end of the respective cage.

Thus, in accordance with the invention, what is now proposed is that the suspension member that serves to abut the suspension band and thus to lift the first reinforcement cage having the suspension band attached thereto is supported differently, namely at or adjacent or in the vicinity of both its ends, each end portion being anchored to a respective one of the first and second anchoring portions of the device. The suspension member, which according to the invention comprises an elongate body which is to some extent hollow -embodiments and examples of which are discussed further below - may thus be supported at or near both its ends in the manner of a simply supported beam, thereby reducing or ameliorating, or even to many practical extents substantially eliminating, the deleterious effects of possibly excessive bolt deflections at locations spaced at relatively large distances “x”, varying as a function of “x3”, from any point of support of the suspension member along its length.

Furthermore, the employment of an elongate suspension member which is to some extent hollow has advantages over the use of a solid bolt of the same mass per unit length, as the different mass distribution gives rise to a suspension member having greater strength and stiffness for a given length, thereby enhancing its load-bearing capability and enabling possibly wider suspension gaps to be employed. Such additional advantages are discussed further below in the context of preferred embodiments of the invention.

This new manner of supporting the suspension member itself also tends to hinder or even substantially prevent any (or any excessive) lateral transverse movement of the spliced reinforcement cages relative to one another during handling, which is also an advantage in assisting the reduction or amelioration of problems associated with excessive lateral loadings on suspension bolts characteristic of the prior art splicing devices.

In many embodiments of the invention the splicing device may be arranged such that the second reinforcement cage on which it is carried is that reinforcement cage which is the uppermost one of the pair of cages, the lowermost reinforcement cage of the pair being the first reinforcement cage having the suspension band attached thereto.

However, in other embodiments of the invention the arrangement may be reversed, so that the second reinforcement cage on which the device is carried is that reinforcement cage which is the lowermost one of the pair of cages, and the first reinforcement cage having attached thereto the suspension band is the uppermost reinforcement cage of the pair. Thus, in different embodiments the orientation of the “first” and “second” reinforcement cages and thus the device may be inverted, whilst the interaction of the device with the relevant parts of both reinforcement cages and its practical function remain substantially the same. For the most part, however, the following discussion of preferred embodiments of the invention will focus on the first orientation defined above, i.e. with the device being carried on the upper, “second” cage and the suspension band being carried on the lower, “first” cage.

In embodiments of the invention the anchoring of the suspension member to the first and second anchoring portions may be accomplished by means of respective first and second anchoring means via which respective ends or end portions of the suspension member are anchorable to the respective anchoring portions. Such first and second anchoring means may each independently comprise any suitable form of mechanical anchoring. Furthermore, in many embodiments different forms of such mechanical anchoring means may be employed for each of the first and second anchoring means, so that the suspension member is anchorable in a different fashion at each of its ends, in particular such as to facilitate the ready and safe task of mounting the suspension member in the device from the outside of the cages.

For example, one suitable form of anchoring means may comprise the suspension member, or at least an end portion thereof, constituting or comprising or being provided with a female engagement portion and the respective anchoring portion constituting or comprising or having provided thereon a corresponding male engagement portion, e.g. in the form of a stub or spigot, the female and male engagement portions being interengageable, such as by virtue of a rotational screw-threaded connection.

Another suitable, corresponding, form of anchoring means may comprise the suspension member, or at least an end portion thereof, constituting or comprising or having provided thereon a male engagement portion, e.g. in the form of a stub or spigot, and the respective anchoring portion constituting or comprising or being provided with a corresponding female engagement portion, the male and female engagement portions being interengageable, such as by virtue of a rotational screw-threaded connection.

Another suitable form of anchoring means may comprise a bayonet-type interengagement means, in which a male bayonet component is provided on one of an end portion of the suspension member and the respective anchoring portion and a female bayonet component is provided on the other of the end portion of the suspension member and the respective anchoring portion.

Another suitable form of anchoring means may comprise a seating or abutment feature, such as a seating or abutment surface, edge, notch, recess, groove, channel, gutter section, tube, flange or slot, provided in or on the respective anchoring portion or a portion thereof and in or into which is accommodatable or seatable a respective portion of, especially a respective end portion of, the suspension member.

Another suitable form of anchoring means may comprise an aperture, through-hole or slot formed in the respective anchoring portion or a portion thereof, into or through or within which the suspension member, or a respective end portion thereof, may be inserted or pass or be seated so as to be anchored therein. In one such form the aperture, through-hole or slot may be formed through the thickness of the material of the respective anchoring portion itself, whereas in another form the aperture, through-hole or slot may be formed in a lug, tube, nut, boss, flange or buttress attached to the respective anchoring portion, and further in yet another form such a lug, tube, nut, boss, flange or buttress, together with a portion of a cage bar to which it may be attached or on which it may be carried, may itself constitute the respective anchoring portion.

In any such embodiments where the anchoring means comprises an aperture, through-hole or slot, the aperture, hole or slot may for example be substantially smooth-walled, e.g. formed by drilling, punching or machining during manufacture of the device before it is attached to the relevant reinforcement cage, or it may be internally screw-threaded. In the case of a non-threaded aperture, hole or slot, any suitable form of retention means, such as a detent, clasp, latch or locking device or arrangement may be provided for securing the relevant end portion of the suspension member therein.

Other suitable forms of anchoring means may comprise various forms or constructions of clip or detent means, practical examples of which are readily available in the art and will be readily apparent to the skilled person.

In one particular preferred embodiment the first anchoring means, via which the suspension member is anchorable to the first anchoring portion of the device, may comprise a seating or abutment surface, edge, notch, recess, groove, channel, gutter section, tube, flange or slot provided in or on the first anchoring portion or a portion thereof and in or into which a respective end portion of the suspension member is accommodatable or seatable, and the second anchoring means, via which the suspension member is anchorable to the second anchoring portion of the device, may comprise interengageable (e.g. via a screw-threaded connection) female and male engagement portions (the latter e.g. being in the form of a stub or spigot) provided on, or constituting part of, the respective suspension member (or end portion thereof) and respective anchoring portion. Some specific examples of such embodiment devices will be described in detail further hereinbelow.

In accordance with the invention the suspension member comprises an elongate hollow body. By “hollow” is meant that the body, which is “elongate” in the sense that it has a generally long length dimension in comparison with its width dimension, comprises at least one void or chamber or channel within the body of the member. In embodiments such a void, chamber or channel preferably extends lengthwise within the body of the suspension member. In some cases the void, chamber or channel (or voids, chambers or channels collectively if more than one is provided within the body of the member) may extend over a major proportion, or even possibly over substantially the whole (or approximately the whole) of the total length of the suspension member.

The void(s), chamber(s) or channel(s) within the body of the suspension member which render(s) it hollow, may be of any suitable cross-sectional shape. A substantially circular cross-section may be preferred in many embodiments, in particular those in which a screw-threaded connection is employed as the anchoring means, although other cross-sectional shapes (e.g. elliptical, arcuate or even rectangular) may be possible, for example depending on the form of the anchoring means via which the end portions of the suspension member are anchorable to the respective anchoring portions of the device.

The external cross-sectional shape of the suspension member, and consequently also the thickness of its walls, may be selected from a variety of shapes and distances, respectively. Generally the thickness of the walls of the suspension member, which walls may in many example forms be of substantially the same thickness in all width directions, will be such as to provide the suspension member with sufficient strength, rigidity, integrity and load-bearing capacity to support and withstand any particular loading force that it is expected to be subjected to when the reinforcement cages are spliced together and suspended.

In one particular practical form, for example, the suspension member may be in the form of an internally screw-threaded cylinder, e.g. of steel, such as an item which is already known and in use in the industry for a different purpose, namely as a coupler for joining together end-to-end lengths of “threadbar” reinforcement cage bar material. Thus, in this case at least one of the ends, especially open ends, of the cylinder constituting the suspension member may itself constitute a female engagement portion for interengagement with a corresponding male engagement portion, e.g. a stub or spigot, provided on the respective anchoring portion of the device to which that end of the cylinder of the suspension member is anchorable. Typically, in such an embodiment, that respective anchoring portion of the device carrying the male engagement portion may be the second anchoring portion of the device, i.e. the one that is transversely spaced from the first anchoring portion attached to the second reinforcement to define the suspension gap in which is trappable the suspension band on the first reinforcement cage when the cages are spliced together.

If desired or necessary, in such an aforementioned embodiment, the opposite end of the cylinder constituting the suspension member from that end constituting the female engagement portion may be provided or formed with insertion means by which or through the assistance of which the cylindrical suspension member may be anchored to the device, in particular to at least the second anchoring portion thereof, and especially to a male engagement portion provided thereon. Such insertion means may for example comprise one or more slots, notches or detents which are engageable by a tool which may optionally be used to facilitate the insertion of and anchoring of the suspension member to the device, especially from transversely outside the reinforcement cages themselves.

In many embodiments of the device of the invention the first and second anchoring portions may be oriented such that their general longitudinal dimensions are generally substantially parallel, or near to parallel, to the longitudinal (i.e. axial) direction of at least the second reinforcement cage, so that the anchoring portions are configured to bound the suspension band of the first reinforcement cage on opposite, transversely spaced apart, sides thereof.

Alternatively or additionally, in many embodiments of the device of the invention the suspension member, when in position bridging the said suspension gap between the first and second anchoring portions, may be oriented such that its general length dimension is generally substantially perpendicular, or normal, or near to perpendicular or normal, to the longitudinal (or axial) direction of at least the second reinforcement cage, so that the suspension member is configured to bound the suspension band of the first reinforcement cage on a generally transversely oriented side or edge thereof.

In many embodiments the suspension member, when in position bridging the said suspension gap between the first and second anchoring portions, may be oriented such that its general length dimension is directed generally transversely towards the longitudinal or central axis of at least the second reinforcement cage - i.e. generally radially or near-radially in the case of substantially cylindrical reinforcement cages. Although in many cases the suspension member may be so oriented generally substantially or approximately transversely towards that longitudinal or central axis (or radially, as the case may be), it is to be understood that within the scope of embodiments of the invention the suspension member may be transversely (or radially, as the case may be) offset or angled relative to the cage’s longitudinal or central axis, that is to say it may be oriented with its length axis at a non-zero angle to a true symmetrically transverse (or radial, as the case may be) direction of the cage, e.g. at an angle of up to about 5 or 10 or 20 or 30 or 40 or 50 or possibly even as much as 60 degrees to the actual symmetrically transverse direction (or radius, as the case may be) of the cage. This offset or angled feature may assist in avoiding fouling or obstruction of the placement of the suspension member by or against cage bars of the first cage during its bringing together with the second cage.

In embodiments the suspension gap defined between the first and second anchoring portions of the device may preferably be of a width sufficient to accommodate at least the thickness of the suspension band on the first reinforcement cage. Preferably however the width of the suspension gap is not excessive such that a significant amount of play or transverse (or radial, as the case may be) movement of the suspension band is possible once it is located and trapped therein.

In some embodiments the upper and/or lower sides or edges of at least the second anchoring portion of the device may be chamfered, bevelled or convexly curved, in order to avoid or facilitate against their fouling with or against cage bars or other structural components of an adjacent reinforcement cage immediately above or below it as the two cages are brought together in the splicing operation, and also to avoid or facilitate against hindrance to the placement into the interior of the spliced cages, once in position in the relevant hole in the ground, of the (circular) concreting tube (“tremmie”) used to fill the hole with wet concrete during the pouring stage of the pile- or wall-forming operation.

According to some embodiments of the device of the invention, the first and second anchoring portions may be constituted by respective arms or legs of a bifurcated support plate, bracket or strip, for example a unitarily formed support plate, bracket or strip. The support plate, bracket or strip may be of a substantially rigid construction so that the respective arms or legs are in a substantially fixed configuration relative to each other. The bifurcated support plate, bracket or strip may conveniently be in the form of a U-shaped plate or strip of rigid material, e.g. which is substantially planar or whose material is of other suitable cross-section (e.g. circular, elliptical, polygonal, etc), preferably metal, e.g. steel (such as that from which the cage bars themselves are formed). Preferably, therefore, the first and second anchoring portions, which may thus be configured so as to be generally parallel to one another, may be connected by a bridging portion, being the base of the preferred U-shaped support plate or strip.

According to some other embodiments of the device of the invention, the first and second anchoring portions may be constituted by respective outer and inner anchoring members of a yoke, especially a plural-sectioned yoke, preferably a three-section yoke, wherein the outer and inner anchoring members (constituting the first and second sections, respectively) are joined by a bridging member (constituting the third section) at least a major portion of which may be arranged generally substantially perpendicular to the outer and inner anchoring members. Each of the first, second and third sections of the yoke may be in the form of a plate, bar or other suitably shaped member, e.g. substantially planar or of another suitable cross-section, such as circular, elliptical, polygonal, etc. The yoke may be of an overall substantially rigid construction so that the respective sections thereof are in a substantially fixed configuration relative to each other. The outer, inner and bridging members, which may be of e.g. steel, may be secured to each other, as appropriate, by e.g. welding, especially elongate fillet welds, in order to optimise the strength of their mutual connections.

When at least two or more of the sections of the yoke are shaped as plates, i.e. with at least one pair of major faces defining therebetween a relatively thin dimension (relative to those faces’ length and width dimensions), the general planes of those plates may be oriented either generally parallel or generally perpendicular relative to one other. In one preferred form the bridging member may be oriented with its width direction generally substantially parallel to the longitudinal directions of each of the outer and inner anchoring members, in order to enhance the overall stiffness and strength of the combined three-section yoke arrangement. Any of these three-section yoke arrangements may be particularly useful in the case of especially wide suspension gaps between the respective anchoring portions of the device, e.g. in embodiments in which it is required to accommodate especially fat or wide cage bars therein. However, in some forms the possible presence of narrow circumferential gaps between cage bars on the transversely inner cage may be accommodated by positioning the inner anchoring member transversely inside the inner cage bars by using a larger bridging member.

It is a particularly preferable feature of many embodiments of the invention that the device may be constructed and configured such that the suspension member is insertable into its anchored position or configuration on the first and second anchoring portions of the device from outside - preferably substantially only from outside - the reinforcement cages, i.e. from transversely (or radially, as the case may be) externally of the reinforcement cages. This removes the need or temptation for workers to place their arms or hands inside the periphery of the cages during the splicing operation, as is generally prohibited nowadays by health and safety criteria. Optionally a tool may be utilised, optionally forming part of a kit of parts including other components of the device, for facilitating the insertion or placement of the suspension member into its anchoring position/configuration.

According to the invention, the first anchoring portion of the device is attached to the second reinforcement cage adjacent one longitudinal end thereof. Thus, in many example forms the first anchoring portion of the e.g. bifurcated support plate or plural-sectioned yoke may be that part of the device which is attached to the second reinforcement cage. The first anchoring portion (or indeed the device generally, in more broadly defined embodiments) may be attached to the second reinforcement cage by any suitable means. In many practical forms this may be by welding directly to one or more of the bars of the second reinforcement cage. The site of the welding attachment may preferably be on one lateral side of a cage bar, i.e. at approximately the same transverse location as the cage bar (relative to the longitudinal or central axis of the cage), although other welding attachment sites are possible, e.g. transversely inwardly of the relevant cage bar.

In alternative forms, the or each device (see further below regarding plural such devices) may be attached to the second reinforcement cage via at least one attachment band. Such an attachment band may be similar in form and construction to the suspension band on the first reinforcement cage, and may be attached, e.g. by welding, to one or more of the cage bars of the second reinforcement cage, and the one or more splicing devices are attached (again e.g. by welding) to the attachment band, rather than being attached directly to the bars of the second reinforcement cage themselves. In some forms, a portion of the attachment band itself may optionally constitute the first anchoring portion, so that a part of the attachment band itself becomes part of the device.

Such arrangements by which the one or more splicing devices are attached to the second reinforcement cage may lend itself particularly favourably to the use of a modular attachment band, wherein the attachment band may comprise a plurality of segments or sections, e.g. arcuate segments, each of which may carry an attached splicing device of the invention or an embodiment thereof. Each such module of the complete attachment band may advantageously be assembled off-site in a dedicated pre-manufacturing stage on a bench-scale set-up, e.g. using an accurate jig, and this may allow a greater degree of accuracy to be achieved in the placement of the splicing devices at the correct locations -especially at correct longitudinal positions relative to the reinforcement cage longitudinal or central axis - so that all the splicing devices end up being attached in as accurate longitudinal positions as possible on the reinforcement cage bars. This may provide for optimum, stable and secure suspension of the suspension band on the first reinforcement cage once the suspension members have been anchored within the device and the two reinforcement cages spliced together ready for lifting.

The suspension band on the first reinforcement cage may be attached thereto by any suitable known means, e.g. by welding directly onto the first reinforcement cage bars, as is already known in the art.

In accordance with embodiments of the invention, any number of individual devices may be used to splice together the first and second reinforcement cages, as desired or as necessary. In many practical embodiments the first and second reinforcement cages may be spliced together using a plurality of devices, each device being a device, preferably a like device, as any defined hereinabove or described herein. In some embodiments the plurality of splicing devices may desirably be arranged substantially equi-angularly or equi-spaced around the periphery of the reinforcement cages. In practice the number of splicing devices used may for example depend on the size, scale or weight of the reinforcement cages to be spliced. For example, in the case of splicing a typical pair of 0.5 tonne pile cages, three devices each disposed at -120° to each other around the pile cage assembly may typically be suitable, although in some cases greater than three such devices each at a smaller disposition angle relative to each other may instead be employed.

Because of the fundamentally different anchoring mechanism by which the suspension members are anchored in the first and second anchoring portions of the devices according to the invention, as compared with the known prior art system relying on solid cantilevered suspension bolts, it may be possible in many example embodiments of the invention to reduce somewhat the thickness of the plate material used to construct the preferred bifurcated support plates, as compared with the flat support plates of the aforementioned prior art system, thereby leading to savings in material costs, as well as less bulky and cumbersome welding attachments, which may also lead to cheaper material and assembly labour costs.

In addition, considering the invention more generally, a primary advantage of a splicing device according to the invention is that since the elongate yet hollow suspension member may in theory have the same mass per metre length as a solid bolt (per the prior art), because it is to some extent hollow its mass is concentrated away from its central lengthwise axis and more towards its outer, e.g. annular, wall surfaces. This enables the suspension member to display both greater strength (i.e. resistance to bending moments and shear forces) and greater stiffness (i.e. resistance to lateral deflection, especially at its mid-span point) as compared with a solid bolt of the same length.

Two corollaries of this are that: (i) the whole anchored suspension member-plus-anchoring portions assembly can withstand greater loadings for a given length span as compared with a solid bolt of equal mass, and/or (ii) the whole anchored suspension member-plus-anchoring portions assembly can span a greater distance of suspension gap than is possible with the same cage load as applied to a solid bolt of equal mass.

Both (i) and (ii) above are relatively advantageous. In particular, feature (ii) allows for a longer anchored suspension member-plus-anchoring portions assembly, meaning that the transversely inner anchoring portion of the device may be located transversely inside the inner layer of reinforcing cage bars of the first reinforcement cage, i.e. so as not to “mesh” with them. This therefore permits the second and first cages to be slid together generally without any interference fit. Furthermore, although the suspension member may in some cases be wider than a solid bolt of the same mass, it may still be relatively narrow compared with the width of the transversely inner anchoring portion of the device, and so generally may not interfere with the cage bars of the first cage sliding past it.

According to a second aspect of the invention there is provided a splicing device perse for splicing a first reinforcement cage to a second reinforcement cage, wherein the first reinforcement cage comprises a suspension band adjacent one longitudinal end thereof, the device being attachable to the second reinforcement cage adjacent a longitudinal end thereof, wherein the said splicing device comprises: a first anchoring portion attachable to said second reinforcement cage adjacent said one end thereof; a second anchoring portion connected to the first anchoring portion and transversely spaced therefrom to define a transverse suspension gap between the first and second anchoring portions; and a suspension member anchorable to the first and second anchoring portions so as to bridge said suspension gap with the suspension band of the first reinforcement cage beatable in said suspension gap, wherein the suspension member comprises an elongate hollow body.

Thus according to this second aspect the splicing device is provided as a discrete item per se, independent of the first and second reinforcement cages that are to be spliced together by means thereof. The structural components of this splicing device perse may for example be pre-manufactured separately and part-assembled as appropriate onto the relevant first and second reinforcement cages in a dedicated off-site facility, ready for transport to a site in question at which the splicing is actually to take place during a construction operation.

Embodiments of the above-defined splicing device per se according to this second aspect of the invention may correspond to any embodiments of the device of the first aspect of the invention discussed above.

According to a third aspect of the invention there is provided a method of splicing a first reinforcement cage to a second reinforcement cage, wherein the first reinforcement cage comprises a suspension band adjacent one longitudinal end thereof and the second reinforcement cage carries adjacent one longitudinal end thereof at least one splicing device according to the second aspect of the invention, wherein the method comprises: (i) bringing together the first and second reinforcement cages into a splicing spatial relationship such that the suspension band of the first reinforcement cage is located within the transverse suspension gap between the first and second anchoring portions of the device on the second reinforcement cage; and (ii) anchoring the suspension member to the first and second anchoring portions of the device so as to bridge the said suspension gap therebetween and thereby enclose the said suspension band in the space defined by the said gap and bounded by the said suspension member.

Thus, in practising embodiments of the above method, once the reinforcement cages have been so spliced they may be lifted together, whereupon the suspension band and the suspension member come into abutment, with the suspension member trapping the suspension band in the suspension gap and preventing its withdrawal therefrom.

Embodiments of the above-defined method according to this third aspect of the invention may employ any embodiment of splicing device perse as discussed above in relation to the first and second aspects of the invention.

According to a fourth aspect, the invention provides, in combination, a first reinforcement cage and a second reinforcement cage, the reinforcement cages being spliced together by a method according to the third aspect of the invention or any embodiment thereof, or by means of a device according to the first or the second aspect of the invention or any embodiment thereof.

Whilst in many practical embodiments of the invention the reinforcement cages to be spliced by the device may be substantially circular in cross-section, in order to form generally cylindrical shaped piles, it is to be understood that the invention is not limited to reinforcement cages of circular cross-section, but other cross-sectional shapes are also possible. For example, reinforcement cages of the pile- or diaphragm wall- types which may be spliced by use of embodiments of the invention may have cross-sections which are non-circular, e.g. elliptical, rectangular, square, L-shaped, T-shaped, or even other shapes.

By use of such alternatively shaped cages, correspondingly alternatively shaped piles, diaphragm walls or other concrete structures may thus be formed. Of course, in the process of drilling the initial hole for insertion therein of the spliced reinforcement cages (optionally in combination with an appropriate shoring device or material), an appropriately shaped drill or form of drilling rig and/or excavation equipment or arrangement may need to be deployed in order to form the correctly shaped hole or void for receiving the correspondingly shaped reinforcement cages therein.

In the case of such embodiments involving the use of non-circular, e.g. rectangular or even other shaped, pile- or diaphragm wall-, or other reinforcement-, cages, where a “radius” is not strictly definable, it is to be understood that as used herein the term “radial” as applied to the spacing or gap between the respective first and second anchoring portions (or anchoring plates, in the case of such embodiments defining same), or as applied to a direction of relative movement of adjacent reinforcement cages, and any like or corresponding term used in a corresponding context, is to be construed as meaning “transverse”, “perpendicular” or “directed toward the centre” relative to the outer peripheral boundary, wall or face of the alternatively-shaped cage in question. Likewise, any reference to a “circumferential” direction should therefore be construed accordingly as meaning parallel to that outer peripheral boundary, wall or face of the cage in question.

Accordingly, in preferred embodiments of the present invention in any of its aspects, each of the above-defined first and second reinforcement cages may be independently selected from a pile cage or a diaphragm wall cage.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. Features described with reference to one embodiment are applicable to all embodiments, unless expressly stated otherwise or such features are incompatible.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments of the present invention in its various aspects will now be described in detail, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a schematic front elevational view of a pair of pile cages about to be spliced using a series of devices according to any of various embodiments of the invention;

Figure 2 is a perspective view of one embodiment of a splicing device according to the invention;

Figure 3(a) is a circumferential side-on view of another embodiment of a splicing device according to the invention;

Figure 3(b) is a radial side-on view of the embodiment splicing device shown in Fig. 3(a);

Figures 4(a), 4(b) and 4(c) are schematic perspective views of some alternative cross-sectional shapes of diaphragm wall cages which may be spliced using devices according to various embodiments of the invention in the formation of correspondingly alternatively-shaped diaphragm walls or other concrete structures; and

Figures 5(a) and 5(b) are, respectively, a side elevational view and a cross-sectional view through that of Figure 5(a) of an example of the splicing together of a pair of mattressshaped reinforcement cages, each of which corresponds to the alternative cross-sectional shape of cage shown in Figure 4(a).

DETAILED DESCRIPTION OF EMBODIMENTS

Referring firstly to Figure 1, here there is shown schematically a pair of pile cages - namely lower pile cage 10 and upper pile cage 20 - ready for being brought together for splicing end-to-end. Each pile cage comprises a respective array of e.g. six elongate steel pile cage bars or rods 12, 22 (although only four are explicitly shown for clarity) of a conventional type, and the cage bars of each group are united into the respective cage 10, 20 by means of a frame comprising a helical steel wire 26 wound therearound and welded thereto (but again only the helical wire frame 26 of the upper cage 20 is explicitly shown for clarity in Figure 1).

In an alternative form of basic construction of each cage 10, 20, instead of a helical wire 26 to unite the respective cage bars 12, 22 of each cage, a series of metal rings or bands, e.g. a plurality of circumferential, especially circular, rings or bands preferably spaced apart in the longitudinal axial direction of the respective cage, may be employed instead.

The upper end of the lower pile cage 10 is shown by way of example as tapered inwardly (or “cranked”), and is optionally fitted at its uppermost end with a terminal end band 40 welded to the bars 12 (and which may lie internally or externally of the cage bars 12) in order to stabilise the free end portions of the bars 12.

The lower pile cage 10 is shown in Figure 1 in a typical condition during a pile construction operation, in which the majority of the length of the lower pile cage has already been lowered into a pile casing 80 located within a drilled hole in the ground, leaving just an upper section of the lower cage 10 exposed and ready for splicing to a second, upper pile cage 20 as shown. The lower pile cage 10 is suspended in the casing 80 by means of a steel trapping band 50 welded onto the cage bars 12 (and which may lie externally or internally of the cage bars 12) at the lower end of the upper section of the lower cage 10. This trapping band 50 is used to trap beneath it a trapping bar or rod 60, thereby preventing the lower pile cage 10 from dropping further into the casing and thus effectively suspending it at a desired height location ready for splicing to the upper cage 20 prior to lowering the spliced cages 10, 20 down inside the pile hole and pouring of wet concrete therein to form the pile.

The lower pile cage 10 is fitted midway up its upper section with a further welded steel band, this one being suspension band 30 (which may likewise be arranged to sit internally or externally of the cage bars 12). It is this suspension band 30 which is now to be used as the means by which the lower pile cage 10 is to be spliced to the upper pile cage 20 in conjunction with the novel splicing devices 50a, 50b according to the invention, as will now be described in further detail with reference to the two example embodiments thereof shown in Figures 2 and 3(a) and 3(b).

Firstly, as shown in Figure 2, each splicing device 50a - and 50b likewise - comprises a three-section yoke 112, 116, 114 which provides the outer and inner anchoring portions of the device to which the suspension member 120 is anchorable to effect the splicing of the cages 10, 20. The yoke comprises a first, radially outer elongate anchoring plate 112 and a second, radially inner elongate anchoring plate 114 arranged generally parallel thereto, these two anchoring plates being rigidly and securely connected via an intermediate elongate bridging plate 116. The plates of the yoke may be made of e.g. steel, for its high strength and stiffness and ability to be easily welded. The first anchoring plate 112 is welded to one of the upper cage bars 22, e.g. using a conventional welding technique, and the bridging plate 116 and second anchoring plate 114 are connected sequentially thereto by corresponding welding, so that the whole rigid yoke 112, 116, 114 is securely attached to the cage bar 22. As an alternative manner of construction of the yoke, the individual plates 112, 114, 116 may instead be joined by respective mortice and tenon joints. The first and second anchoring plates 112, 114 of the yoke are separated by a transverse radial suspension gap G, which is of a sufficient width to comfortably accommodate therewithin the thickness of the suspension band 30 of the lower pile cage 10.

The bridging plate 116 is preferably oriented as shown, with its width dimension oriented generally vertically, i.e. generally parallel to the general planes of the first (outer) and second (inner) anchoring plates 112, 114, and the general plane of the bridging plate 116 being oriented substantially normal to the general planes of both the first (outer) and second (inner) anchoring plates 112, 114. In this manner an especially stiff and strong physical yoke arrangement is produced. The various sections 112, 116, 114 of the yoke are joined together, and the first (radially outer) anchoring portion 112 is attached to the outer cage bar 22, preferably by elongate fillet welds, as at 190, in order to further optimise the arrangement’s structural strength and integrity.

This 3-plate structural form of yoke may in some practical instances be preferred over for example an alternative U-shaped unitarily-formed plate or strip providing corresponding first (radially outer) and second (radially inner) anchoring portions, for example in the case of needing to employ particularly wide suspension gaps between the respective anchoring portions to take account of particularly fat cage bars, and since it may lead to an improved degree of stiffness and structural strength of the overall anchoring arrangement.

For the purpose of closing the suspension gap G once the suspension band 30 on the first pile cage 10 has been inserted therein, a suspension member 120 is provided, which in this embodiment is in the form of a hollow, internally threaded steel cylinder, such as a coupler that is current known and used in the industry for joining together end-to-end lengths of “threadbar” reinforcement cage bar material. The hollow cylindrical void which extends lengthwise within the cylindrical suspension member 120 has the effect of moving its principal mass concentration away from its central length axis and more towards the outer cylindrical surfaces of the member. This enables the suspension member 120 to display both greater strength (i.e. resistance to bending moments and shear forces) and greater stiffness (i.e. resistance to lateral deflection, especially at its mid-span point) as compared with a solid steel bolt of the same length. The practical advantages of this have already been discussed hereinabove.

Each end portion of the suspension member 120 is anchored to the respective first, radially outer anchoring plate 112 and second, radially inner anchoring plate 114 by its own respective anchoring means. In this embodiment the radially inner anchoring means, via which the suspension member 120 is anchored to the radially inner anchoring plate 114, is constituted by one end portion of the cylindrical suspension member 120 inherently constituting a female, internally screw-threaded engagement portion, which is interengageable with a male stub or spigot 130 welded (again e.g. by fillet welds 190) onto the radially inner anchoring plate 114. The stub or spigot 130 is externally screw-threaded correspondingly to the internal screw-thread on the inside of the cylindrical suspension member 120, so that the resulting female-male connection can be effected by a simple rotation of the cylindrical suspension member 120.

To assist this insertion and anchoring of the suspension member 120, especially from radially outside the cages 10, 20, a tool may be used (not shown), which may be designed to engage with a pair of slots or notch formations 146 on the opposite end of the cylindrical suspension member 120 from that end which unites with the male stub or spigot 130. For simplicity, such a tool may for example comprise a short length of “threadbar” cage bar material which initially penetrates the first few turns of the internal thread of the suspension member 120 while it is being inserted and anchored, yet can then be simply removed therefrom by reverse-unscrewing.

The radially outer anchoring means, via which the suspension member 120 is anchored to the radially outer anchoring plate 112, is constituted by a somewhat simpler arrangement, namely a simple abutment seating of an end portion of the cylindrical suspension member 120 in a V-shaped recess, trough or notch 140 formed in an upper-facing edge or face of the radially outer anchoring plate 112. The recess, trough or notch 140 may have any suitable shape to assist in the secure seating or abutment of the cylindrical suspension member 120 thereon or therein, so that once the cages 10, 20 have been spliced and are being lifted, the suspension band 30 on the first pile cage 10 bears against the abuttingly seated suspension member 120 and exerts its load in the longitudinal axial direction of the cages, thereby retaining the suspension member 120 in its abutting anchored position in the recess, trough or notch 140, with minimised tendency for its being dislodged therefrom.

Thus, once the cylindrical suspension member 120 has been anchored to each of the radially inner and outer anchoring plates 114, 112 via the respective anchoring means, it becomes anchored to the device at both its ends in the manner of a conventional beam, so that the central portion of the suspension member 120 - namely that portion located within the suspension gap G between the outer and inner anchoring plates 112, 114 - is the only part of the suspension member 120 to have applied thereto downward loading forces corresponding to the weight of the lower pile cage 10 as the latter is lifted by means of the abutting engagement of the suspension member 120 (effectively carried by the upper pile cage 20) with and against the underside of the suspension band 30 (carried by the lower pile cage 10).

Since by this arrangement any such downward loading force on the suspension member 120 is resisted at both its ends - which is in contradistinction to the prior art cantilevered device proposed in EP1963579A (referred to above) for example, where the suspension bolts are anchored and supported at only one of their ends - then any tendency of the suspension member 120 here to flex or deform is minimised, leading to a much more reliable and mechanically more stable and safer suspending mechanism for carrying the weight of the lower pile cage 10 using the abutting engagement of the suspension member 120 with the underside of the suspension band 30.

Any number of like splicing devices 50a, 50b etc may be provided in the apparatus as shown in Figure 1, preferably spaced equi-angularly around the pile cage assembly. By way of example, only two such splicing devices 50a, 50b are shown in Figure 1 for clarity, but typically three such devices may be used, spaced at 120° relative to each other around the periphery of the assembly, although more than three like devices may be utilised, if that is desired or necessary for example depending on the overall weight of the lower pile cage to be spliced and carried.

Starting from the arrangement shown schematically in Figure 1, the upper pile cage 20 may be lowered, e.g. typically by use of a crane, such as indicated by arrow “A”, to approach the lower pile cage 10 anchored in its pile casing 80, until it reaches the required location with (i) each splicing device 50a, 50b positioned over the suspension band 30 on the lower pile cage 10 with the device’s first and second anchoring portions 112, 114 lying to each lateral side of the suspension band 30, and (ii) the male stub or spigot and the seating recess, trough or notch 140 in the first and second anchoring portions 112, 114 positioned just beneath the suspension band 30. In this configuration it is then a simple job to insert and/or screw home each suspension member 120 into its respective anchored configuration, in which final configuration they retain the suspension band 30 within the radially transverse suspension gap G between the anchoring portions 112, 114 with the suspension member 120 bounding the suspension gap G at its lowermost end so as to fully retain and trap the suspension band 30 therewithin.

Thus, the lower and upper pile cages 10, 20 are thereby spliced together, enabling them now to be lifted or lowered together - accurately, stably and safely - either for further movement around the site or, for example, for lowering into the pile casing ready for splicing yet another pile cage to the upper end of the upper pile casing 20 in a corresponding like manner.

Turning to Figures 3(a) and (b), here there is shown another, similar, embodiment of splicing device according to the invention, so corresponding features of the device of this embodiment which correspond to already discussed features of the embodiment of Figure 2 are designated using the same reference numerals but incremented by 100.

In this embodiment, however, the seating recess, slot, trough or notch 240 in which fits the cylindrical suspension member 220 so as to be anchored therein is configured differently, and perhaps more efficiently for better securement of the cylindrical suspension member 220 therein. In this example the recess, slot, trough or notch 140 is substantially U-shaped (as shown in Figure 3(b)), and pointed in a generally upward yet inclined angle (e.g. of the order of around 10 or 20 or 30 up to about 50 or 60 or 70°) to the horizontal (i.e. radial direction normal to the cages’ longitudinal axis). With the retention recess, slot, trough or notch oriented in this way, the insertion and retention therein of the cylindrical suspension member 220 as it is anchored in place to the first and second anchoring portions 212, 214 is made that much easier and more secure a fixing, thereby possibly leading to an improved strength, rigidity and security of connection to the anchoring portions 212, 214 of the device.

In other respects the construction and operation of the device of the embodiment of Figures 3(a) and 3(b) correspond closely to, or are substantially the same as, those of the embodiment of Figure 2.

In a modification to either of the embodiments shown in Figures 2 and 3, it is possible to provide the radially outer end of the suspension member 120, 220 with an external flange, washer or enlarged head element, e.g. circular or annular in shape, which is configured to abut or sit against the radially outer side or face of the first, outer anchoring plate 112, 212 when the suspension member 120, 220 is anchored thereto, in order to improve the stability of the anchored arrangement.

As already mentioned hereinabove, it is possible within the scope of this invention for reinforcement cages to be employed which are non-circular in cross-section, for use in forming correspondingly non-circular shaped piles, diaphragm walls or other concrete structures. Figures 4(a), 4(b) and 4(c) show schematically some examples of such alternative cross-sectional peripheral outer shapes of reinforcement cages which may be spliced by use of any of the above defined and described embodiments of the invention. For example, Figure 4(a) shows a reinforcement cage having a generally rectangular cross-section (i.e. is generally “mattress-shaped”), Figure 4(b) shows a T-sectioned reinforcement cage, and Figure 4(c) shows an L-shaped or “corner” reinforcement cage.

The manner in which such alternatively shaped reinforcement cages may be spliced using devices in accordance with embodiments of the invention will be readily understood by persons skilled in the art from the foregoing description taken in conjunction with the accompanying drawings showing the splicing of circular pile cages.

However, by way of an additional example, Figures 5(a) and 5(b) (the latter being a median sectional view through the former) show the splicing together of a pair of mattress-shaped reinforcement cages (e.g. each of the shape shown in Figure 4(a)). As shown in Figures 5(a) and 5(b), an upper reinforcement cage 20 is being spliced to a lower reinforcement cage 10 by use of a series of laterally equi-spaced like devices 50a according to any foregoing, or other, embodiment of the invention, e.g. that according to the embodiments described in either of Figures 2 and 3. Features of the alternative arrangement shown in Figures 5(a) and 5(b) which thus correspond to those respective features of the arrangements of Figures 2 and 3 are shown in the former by the same reference numerals.

It is to be understood that in the foregoing descriptions of various constructional arrangements and variations thereof of splicing devices according to embodiments of the invention that any and all individual features thereof may be taken independently or in any combination and applied in that manner to any and all embodiments, not only to those in the context of which such feature(s) have been specifically introduced, described or illustrated. In other words, any feature(s) described with reference to one embodiment is/are applicable to all embodiments, unless expressly stated otherwise or such features are incompatible.

It is furthermore to be understood that the above description of embodiments of the invention in terms of their various features and aspects has been by way of non-limiting example(s) only, and various modifications may be made from what has been specifically described and illustrated whilst remaining within the scope of the invention as claimed.

Claims

1. A device for splicing a first reinforcement cage to a second reinforcement cage, wherein the first reinforcement cage comprises a suspension band adjacent one longitudinal end thereof and the second reinforcement cage carries the said device adjacent one longitudinal end thereof, the device comprising: a first anchoring portion attached to the second reinforcement cage adjacent said one end thereof; a second anchoring portion connected to the first anchoring portion and transversely spaced therefrom to define a transverse suspension gap between the first and second anchoring portions; and a suspension member anchorable or anchored to the first and second anchoring portions so as to bridge said suspension gap with the suspension band of the first reinforcement cage located in said suspension gap, wherein the suspension member comprises an elongate hollow body.

2. A device according to claim 1, wherein the suspension member is locatable, arrangeable or configurable, or is located, arranged or configured, relative to the respective anchoring portions such that the suspension member is substantially fixed or immovable relative thereto at least in a direction corresponding to, or generally substantially parallel to, a longitudinal direction of the first and second reinforcement cages in which loading force acts when the reinforcement cages are spliced together and suspended.

3. A device according to claim 1 or claim 2, wherein the suspension member is anchored to the first and second anchoring portions at or adjacent its respective ends, whereby the suspension member is supported at or adjacent both its ends in the manner of a simply supported beam.

4. A device according to any one of claims 1 to 3, wherein the device is arranged such that the second reinforcement cage on which the device is carried is that reinforcement cage which is the uppermost one of the pair of reinforcement cages, the lowermost reinforcement cage of the pair being the first reinforcement cage and having the suspension band attached thereto.

5. A device according to any one of claims 1 to 3, wherein the device is arranged such that the second reinforcement cage on which the device is carried is that reinforcement cage which is the lowermost one of the pair of reinforcement cages, and the first reinforcement cage, having attached thereto the suspension band, is the uppermost reinforcement cage of the pair.

6. A device according to any preceding claim, wherein the anchoring of the suspension member to the first and second anchoring portions is accomplished by means of respective first and second anchoring means via which respective ends or end portions of the suspension member are anchorable to the respective anchoring portions.

7. A device according to claim 6, wherein the first and second anchoring means each independently comprises a mechanical anchoring means, and different forms of such mechanical anchoring means are employed for each of the first and second anchoring means, whereby the suspension member is anchorable or anchored in a different fashion at each of its ends.

8. A device according to claim 6 or claim 7, wherein either: (i) at least one of the first and second anchoring means comprises the suspension member, or at least an end portion thereof, constituting or comprising or being provided with a female engagement portion and the respective anchoring portion constituting or comprising or having provided thereon a corresponding male engagement portion, the female and male engagement portions being interengageable, optionally by virtue of a rotational screw-threaded connection; or (ii) at least one of the first and second anchoring means comprises the suspension member, or at least an end portion thereof, constituting or comprising or having provided thereon a male engagement portion, and the respective anchoring portion constituting or comprising or being provided with a corresponding female engagement portion, the male and female engagement portions being interengageable, optionally by virtue of a rotational screw-threaded connection.

9. A device according to claim 6 or claim 7, wherein at least one of the first and second anchoring means comprises a bayonet-type interengagement means, in which a male bayonet component is provided on one of an end portion of the suspension member and the respective anchoring portion and a female bayonet component is provided on the other of the end portion of the suspension member and the respective anchoring portion.

10. A device according to claim 6 or claim 7, wherein at least one of the first and second anchoring means comprises a seating or abutment feature, optionally a seating or abutment surface, edge, notch, recess, groove, channel, gutter section, tube, flange or slot, provided in or on the respective anchoring portion or a portion thereof and in or into which is accommodatable or seatable a respective end portion of the suspension member.

11. A device according to claim 6 or claim 7, wherein at least one of the first and second anchoring means comprises an aperture, through-hole or slot formed in the respective anchoring portion or a portion thereof, into or through or within which the suspension member, or a respective end portion thereof, may be inserted or pass or be seated so as to be anchored therein.

12. A device according to claim 11, wherein: (i) the aperture, through-hole or slot is formed through the thickness of the material of the respective anchoring portion itself; or (ii) the aperture, through-hole or slot is formed in a lug, tube, nut, boss, flange or buttress attached to the respective anchoring portion; or (iii) the aperture, through-hole or slot is formed in a lug, tube, nut, boss, flange or buttress, and the said lug, tube, nut, boss, flange or buttress, together with a portion of a cage bar to which it is attached or on which it is carried itself constitutes the respective anchoring portion; and/or (iv) in any of cases (i), (ii) or (iii) the aperture, through-hole or slot is substantially smooth-walled or internally screw-threaded, and optionally in the case of a non-threaded aperture, hole or slot a retention means or locking device or arrangement is provided for securing the relevant end portion of the suspension member therein.

13. A device according to claim 6 or claim 7, wherein the first anchoring means, via which the suspension member is anchorable to the first anchoring portion of the device, comprises a seating or abutment surface, edge, notch, recess, groove, channel, gutter section, tube, flange or slot provided in or on the first anchoring portion or a portion thereof and in or into which a respective end portion of the suspension member is accommodatable or seatable, and the second anchoring means, via which the suspension member is anchorable to the second anchoring portion of the device, comprises interengageable female and male engagement portions provided on, or constituting part of, the respective suspension member and respective anchoring portion.

14. A device according to any preceding claim, wherein the suspension member comprises at least one void or chamber or channel within the body thereof and extending lengthwise therewithin.

15. A device according to claim 14, wherein the void(s), chamber(s) or channel(s) extend over a major proportion of the total length of the suspension member.

16. A device according to claim 14 or claim 15, wherein the void(s), chamber(s) or channel(s) within the body of the suspension member are substantially circular in cross-sectional shape.

17. A device according to claim 16, as dependent through claim 8, wherein the suspension member is an elongate, internally screw-threaded, hollow cylinder, one female engagement end portion of which is interengageable with a respective male engagement stub or spigot provided on the respective anchoring portion of the device.

18. A device according to claim 17, wherein an opposite end of the cylinder constituting the suspension member from that end constituting the female engagement portion is provided or formed with insertion means by which or through the assistance of which the cylindrical suspension member is anchorable to at least the second anchoring portion thereof.

19. A device according to claim 18, wherein the said insertion means comprises one or more slots, notches or detents which are engageable by a tool, said tool optionally being usable to facilitate the insertion of and anchoring of the suspension member to the device from transversely outside the reinforcement cages themselves.

20. A device according to any preceding claim, wherein the first and second anchoring portions are oriented such that their general longitudinal dimensions are generally substantially parallel, or near to parallel, to the longitudinal direction of at least the second reinforcement cage, so that the anchoring portions are configured to bound the suspension band of the first reinforcement cage on opposite, transversely spaced apart, sides thereof.

21. A device according to any preceding claim, wherein the suspension member, when in position bridging the said suspension gap between the first and second anchoring portions, is oriented such that its general length dimension is generally substantially perpendicular, or normal, or near to perpendicular or normal, to the longitudinal direction of at least the second reinforcement cage, so that the suspension member is configured to bound the suspension band of the first reinforcement cage on a generally transversely oriented side or edge thereof.

22. A device according to any preceding claim, wherein the suspension member, when in position bridging the said suspension gap between the first and second anchoring portions, is oriented such that its general length dimension is directed generally transversely towards the longitudinal or central axis of at least the second reinforcement cage.

23. A device according to any preceding claim, wherein the suspension member, when in position bridging the said suspension gap between the first and second anchoring portions, is transversely offset or angled relative to the cage’s longitudinal or central axis, such that the suspension member is oriented with its length axis at a non-zero angle to a true symmetrically transverse direction of the cage.

24. A device according to any preceding claim, wherein the first and second anchoring portions are constituted by respective legs or arms of a bifurcated support plate, bracket or strip.

25. A device according to claim 24, wherein the bifurcated support plate, bracket or strip is in the form of a U -sectioned plate or strip of rigid material.

26. A device according to any one of claims 1 to 23, wherein the first and second anchoring portions are constituted by respective outer and inner anchoring members of a yoke, wherein the outer and inner anchoring members (constituting first and second sections of the yoke) are joined by a bridging member (constituting the third section of the yoke) arranged substantially perpendicular to the outer and inner anchoring members, the bridging member optionally being oriented with its width direction generally substantially parallel to the longitudinal directions of each of the outer and inner anchoring members.

27. A device according to any preceding claim, wherein the transverse suspension gap defined between the first and second anchoring portions of the device is of a width sufficient to accommodate at least the thickness of the suspension band on the first reinforcement cage.

28. A device according to any preceding claim, wherein the upper and/or lower sides or edges of at least the second anchoring portion is/are chamfered, bevelled or convexly curved.

29. A device according to any preceding claim, wherein the device is constructed and configured such that the suspension member is insertable into its anchored position on the first and second anchoring portions of the device substantially only from outside the reinforcement cages.

30. A device according to any preceding claim, wherein the device is attached to the second reinforcement cage via at least one attachment band.

31. A device according to claim 30, wherein the attachment band comprises a plurality of segments, the said device being carried on one or a respective one said segment of the attachment band.

32. A device according to any preceding claim, wherein a transversely outer end of the suspension member carries an external flange, washer or head element, which flange, washer or head element is configured to abut or sit against a transversely outer side or face of the first anchoring portion when the suspension member is anchored thereto in order to improve the stability of that anchored arrangement.

33. A device according to any preceding claim, wherein each of the first and second reinforcement cages is independently selected from a pile cage or a diaphragm wall cage.

34. In combination, a first reinforcement cage and a second reinforcement cage, the reinforcement cages being spliced together using a device according to any one of claims 1 to 33.

35. In combination, a first reinforcement cage and a second reinforcement cage, the reinforcement cages being spliced together using a plurality of devices, each device being a device according to any one of claims 1 to 33.

36. A splicing device per se for splicing a first reinforcement cage to a second reinforcement cage, wherein the first reinforcement cage comprises a suspension band adjacent one longitudinal end thereof, the device being attachable to the second reinforcement cage adjacent a longitudinal end thereof, wherein the said splicing device comprises: a first anchoring portion attachable to said second reinforcement cage adjacent said one end thereof; a second anchoring portion connected to the first anchoring portion and transversely spaced therefrom to define a transverse suspension gap between the first and second anchoring portions; and a suspension member anchorable to the first and second anchoring portions so as to bridge said suspension gap with the suspension band of the first reinforcement cage beatable in said suspension gap, wherein the suspension member comprises an elongate hollow body.

37. A method of splicing a first reinforcement cage to a second reinforcement cage, wherein the first reinforcement cage comprises a suspension band adjacent one longitudinal end thereof and the second reinforcement cage carries adjacent one longitudinal end thereof at least one splicing device according to any one of claims 1 to 33, wherein the method comprises: (i) bringing together the first and second reinforcement cages into a splicing spatial relationship such that the suspension band of the first reinforcement cage is located within the transverse suspension gap between the first and second anchoring portions of the device on the second reinforcement cage; and (ii) anchoring the suspension member to the first and second anchoring portions of the device so as to bridge the said suspension gap therebetween and thereby enclose the said suspension band in the space defined by the said gap and bounded by the said suspension member.

38. In combination, a first reinforcement cage and a second reinforcement cage, the reinforcement cages being spliced together by a method according to claim 37 or by means of a device according to claim 36.

39. A device for splicing a first reinforcement cage to a second reinforcement cage, or a combination of a first reinforcement cage and a second reinforcement cage spliced together, or a splicing device perse, or a method of splicing a first reinforcement cage to a second reinforcement cage, substantially as any described herein with reference to any of the accompanying drawings.