Patent Description:
Post-tensioning is a method of reinforcing (strengthening) concrete or other materials with high strength steel strands or bars, referred to in the art as 'tendons'. For example, a concrete floor plate structure in a building may be post-tensioned to increase the strength, rigidity and integrity of the building. Post-tensioning is used in multi-storey buildings or in buildings where the floors are intended to have long spans uninterrupted by vertical pillars.

When pouring a building floor as a single plate of cementitious material, the floor is formed by making the floor in sections or individual slabs, which are poured at different times to each other and interconnected by suitable tendons such as wire cables or rods, to form the more or less continuous flooring. After pouring and during curing, the individual sections of the floor tend to move with respect to each other as the building settles. This means that the joint connecting the sections or slabs must be capable of accommodating this relative movement. Further, pre-compression forces exist in each of the sections or slabs, on either side of the joint. These internal forces in the sections or slabs result in the sections or slabs contracting, to thereby open up the joint laterally (i.e. in longitudinal and lateral-sideways directions).

Temporary movement connectors are known which incorporate a tendon, which connectors provide a joint between adjacent sections or slabs, and which connectors accommodate relative movement between such adjacent sections or slabs (i.e. as a result of the pre-compression forces existing in each of the sections or slabs). The tendons of such temporary movement connectors may be post tensioned.

In this regard, each temporary movement connector can accommodate the relative movement of individual floor sections or slabs, before the joint (i.e. connector) is locked by the various sections and components of the temporary movement connector being sealed to one another permanently. Once the temporary movement connector is sealed, the permanent post-tensioned floor can provide a more or less continuous floor or similar of the building. However, if there is insufficient or poor transfer of post tensioning pre-compression forces and that also result in differential movement between adjacent sections/slabs, and prior to the temporary movement connector being locked, the sections/slabs can be at risk of cracking which can thereby reduce the longevity and the integrity of the resulting floor plate.

Some prior art temporary movement connectors have attempted to address the significant difficulty in sealing the connector prior to locking. In some temporary movement connectors, inadequate sealing of hollow components of the connector may allow the ingress of concrete or cement fines into the connector prior to post-tensioning. This may inhibit the temporary movement connector from performing as designed and may result in a weak joint.

For example, some prior temporary movement connectors have made use of a sealing screen incorporating a flexible elastic membrane that bridges between a female housing and male positioner. The female housing may be cured into a first surface and the male positioner may be cured into a second surface along with a dowel bar, the dowel bar passing through the male positioner into the female housing. The male positioner may have an aperture comprising a sealing ring that is adapted to sealingly engage the dowel bar and may thus prevent concrete or cement fines from entering the connector through the aperture. In use, because the male positioner is cured into the same surface as the dowel bar, the two components do not move relative to one-another. Thus, to the accommodate for any lateral, vertical or telescopic movement between the two surfaces relative to one-another, the flexible elastic membrane that bridges between the male positioner and female housing may flex to allow for relative movement between the male positioner and female housing, whilst maintaining the sealed connection between the components of the temporary movement connector around the dowel prior to locking. One issue that may arise from such prior art temporary movement connectors, is that the elastic membrane can be prone to failure whilst adapting to the relative movement of the components of the connector. For example, the elastic membrane may become worn and tear when stretched telescopically.

A further issue that has arisen in some prior art temporary movement connectors has been the inability to reliably inhibit the dowel bar and/or connector housing from failing in tension force transfer once it has been locked. In some forms, the dowel bar has been provided with a locking pin that engages a slot along the dowel, the locking pin is then surrounded by grout to lock the dowel bar in tension and shear transfer to the grout. In other forms, at least one of the dowel bar and dowel bar housing have been provided with ribs therealong internally and externally to the housing. These ribs are surrounded by grout when the dowel bar is locked within the temporary movement connector. However, one issue that has arisen from such prior art temporary movement connectors is that the locking pin, ribs, and cementitious material that surrounds the locking pin and/or ribs may be prone to shearing or fracturing due to the significant tension forces arising from relative movement of the adjacent sections/slabs. This may result in either the dowel bar or the entire temporary movement connector failing.

<CIT> discloses a connector comprising a housing having an enlarged seal housing at a first end and a sealing screen adapted for receipt in the enlarged seal housing. The sealing screen incorporates an elastic membrane that surrounds an aperture.

The aperture is adapted to sealingly engage a dowel bar.

Due to such engagment movement of the dowel bar laterally, vertically or telescopically is accomodated by the elastic membrane in a manner that ensures that the dowel bar remains sealingly engaged by the aperture.

The present inventions provides a connector according to claim <NUM>.

Disclosed herein is a connector for use in forming a joint between a first surface and a second surface. The first and second surfaces may be defined by sections, slabs or plates that may be formed adjacent to one-another, with the connector acting as a moveable bridge therebetween. Typically, at least one of the adjacent sections, slabs or plates is horizontal (e.g. a forming part of the floor). Prior to locking, the connector to allows a temporary release of restraining effects of the surfaces relative to one another (i.e. the connector allows for differential movement of the surfaces relative to one another). This may assist in ensuring that the maximum amount of post-tensioning pre-compression force can be transferred into the surfaces prior to being locked.

The connector comprises a housing and a dowel bar, hereafter referred to as a tendon. When the tendon is installed within the housing, a portion of the tendon protrudes from the housing through a seal. The seal is configured to sealably cover an open end of the housing around the tendon such that, prior to the connector being locked, the seal protects against the ingress of grout and/or cementitious material into the housing through the open end. Furthermore, the seal is configured such that, prior to locking, the tendon can move through the seal and laterally sideways across the open end together with at least a portion of the seal.

Thus, said at least a portion of the seal is able to seal the housing open end and to seal around the tendon, and yet the tendon can move the portion of the seal laterally across the open end, and further the tendon can be moved longitudinally through the seal at the open end. As set forth herein, because the tendon moves said at least a portion of the seal laterally across the open end, and because the tendon can move longitudinally through the seal, said at least a portion of the seal is able to be configured in a more robust and reliable format (e.g. some or all of the seal may primarily be constructed of a high strength and durable material, such as a metal, metal alloy, composite, etc.). This contrasts the present seal with the known and less reliable flexible elastic membranes of the prior art.

In an embodiment, the seal may solely comprise a sealing element that is configured to be retained within a sleeve. In another embodiment, the seal may comprise both the sealing element and the sleeve, in which case the sealing element may define the portion of the seal that moves laterally sideways together with the tendon.

In either case, the sleeve may be affixed at the open end of the housing. Thus, the sleeve, together with the sealing element, can close the housing open end. Further, the lateral sideways movement of the tendon causes the sealing element to be laterally displaced within and relative to the sleeve. Longitudinal movement of the tendon relative to the housing may be accommodated for by the tendon passing through the sealing element into or out of the housing. Further, the sleeve can restrain the sealing element against moving longitudinally together with the tendon. This arrangement may further improve the reliability and robustness of the seal by removing the need for the seal to move along more than one plane (e.g. laterally and telescopically like the flexible elastic membranes of the prior art) relative to the housing. In other words, the present arrangement is such that the sealing element is constrained by the sleeve to move only in one plane.

the sealing element is retained captively within the sleeve. According to the invention, the sealing element comprises a flat plate that is configured to move laterally with the tendon in use. In some embodiments, in use, the housing may be embedded within a cured first surface such that the open end of the housing and/or the sleeve is contiguous with a face of the surface (i.e. the housing open end is accessible). In such embodiments, only the portion of the tendon that protrudes from the housing through the seal may become embedded within an adjacent cured second surface. By reducing the number of moving components, the connector may be more robust and may perform more consistently.

In an embodiment, a semisolid or pseudo-plastic fluid may be arranged between the sealing element and the sleeve such that a grout and/or cementitious material is prevented from flowing through the seal between the sleeve and the sealing element. Thus, the semisolid or pseudo-plastic fluid may form part of the "seal". In an embodiment, the semisolid or pseudo-plastic fluid may be grease. A semisolid or pseudo-plastic fluid may also advantageously reduce frictional resistance between the sealing element and the sleeve, thus enabling the sealing element to slide laterally sideways more easily within the sleeve when moved by the tendon.

In an embodiment, the sealing element may comprise an aperture therethrough that is closely dimensioned so as to sealably engage the tendon, whilst permitting the tendon to slide longitudinally back-and-forth therethrough in use. Thus, the closely dimensioned aperture can form a part of the "seal". Hence, prior to the connector being locked (e.g. by grout), the closely dimensioned aperture may protect against the ingress of grout and/or cementitious material into the housing through the open end whilst not inhibiting longitudinal movement of the tendon relative to the housing or the seal. In some embodiments, the aperture may comprise an O-ring around its perimeter, with the O-ring being adapted to sealably engage the tendon. Thus, the O-ring can also form a part of the "seal".

In some embodiments, when the sealing element is a flat plate, it may be formed from a stiff and/or rigid material, whereas the O-ring may be formed from a flexible and/or resilient material. The flexible and/or resilient material of the O-ring may in some embodiments be formed from an elastomeric material such as a rubber. The rubber may still have sufficient rigidity to resist deformation when a lateral force is applied by the tendon against the rim of the O-ring.

In some embodiments the flat plate may be formed from metal. In some embodiments, the flat plate and O-ring may be made of the same material, or may be configured to form a single body. In some embodiments, when the flat plate and tendon are formed from metal, there may be a metal-to-metal connection between the flat plate and tendon.

Also disclosed is a connector for use in forming a joint between a first surface and a second surface, wherein the connector comprises a housing and a tendon. When the tendon is installed within the housing, a first portion of the tendon is retained within the housing, and a second portion of the tendon protrudes from the housing through a seal. The tendon first portion has a configuration such that the tendon first portion cannot pass out of the housing via the seal and is thus retained within the housing. Once the tendon first portion has been inserted into the housing through the seal and configured, the configured tendon first portion prevents the removal of the tendon first portion back through the seal. Thus, even prior to locking of the tendon, the tendon may be configured in such a manner that it is restricted from being pulled out of the housing through the seal, whilst still permitting some lateral and longitudinal movement of the tendon within the housing. Unlike a tendon that relies on ribs that are integrally formed therealong to grip the surrounding grout when locked, or a locking clip which remains loose until set in place by the surrounding grout (and may still be prone to failure such as shearing), the configured tendon first portion is able to prevent removal of the tendon even prior to locking of the tendon. The configured tendon first portion may thus improve the overall reliability of the connector.

The configuration of the tendon first portion may involve a fastening, screwing, bolting, clipping, welding or other means of deforming and/or securing another component to the tendon. The configuration of the tendon first portion may involve a formation that is integral (e.g. integrally formed) with a remainder of the tendon.

For example, in an embodiment, the configuration of the tendon first portion may comprise an enlarged formation that is located at or is of the tendon. The enlarged formation may be of a size and/or shape such that the enlarged formation prevents the tendon first portion from passing out of the housing (e.g. via the seal).

In an embodiment, the housing may comprise a passage that extends from the seal. The housing may also comprise a chamber located along the passage (e.g. at an end of the passage). The chamber can be adapted such that the configured tendon first portion is retained within the chamber. Thus, in such embodiments, the movement of the tendon through the seal may be restricted by the range of longitudinal motion of the configured tendon first portion within the chamber. For example, in embodiments where the configuration of the tendon first portion is an enlarged formation, the enlarged formation may be of a size and/or shape such that it is prevented from being removed from within the chamber. By way of further example, when the enlarged formation is moved towards a surface of the chamber that is adjacent the passage, the enlarged formation may interact with the surface of the chamber and may thus be prevented from entering partly or wholly into the passage.

In an embodiment, the seal may be located at one end of the passage and the chamber may be located at an opposite end of the passage. The tendon may thus extend through the passage between the chamber and seal. In an embodiment, the enlarged formation may be located at the end of the tendon first portion.

In an embodiment, the enlarged formation may be an anchor block dimensioned such that it is prevented from moving through the passage. However, the anchor block may be dimensioned such that it is able to move longitudinally and laterally within the chamber along with movement of the tendon. A tension load on the tendon may thus be converted into a compression load, either when the anchor block contacts the chamber wall, or when surrounding grout (or cementitious material) that is later added into the chamber to lock the tendon therein holds captive (i.e. locks) the anchor block. This compression load can thus be dispersed between the anchor block, the surrounding grout/cementitious material (when present), the chamber wall and the surrounding surface (e.g. floor/wall slab) in which the connector is embedded.

For example, in embodiments when the anchor block and chamber are made from steel, and once grout/cement has been added into the chamber, the tensile load applied to the tendon may be initially distributed into the grout/cement to be compressed between the anchor block and the chamber wall, with this load then further distributed out of the chamber to the surrounding surface (i.e. into the section/slab/plate that surrounds the exterior surface of the chamber). The configuration is such as to convert tensile load applied to the tendon into a compressive load, whereby the likelihood of failure of the connector may be reduced, as grout (and cementitious material in general) has increased performance when under compressive loads than when under tensile or shear loads.

In some configurations of the anchor block, a portion of the anchor block may enter the passage, however, typically the anchor block may be of a size and/or shape such that the whole anchor block is prevented from entering and passing through the passage.

In an embodiment, the anchor block may comprise a first contact face that forms a plane that is angled with respect to a longitudinal axis of the tendon. The first contact face may be adapted to oppose so as to engage a corresponding interior facing wall of the chamber that is located adjacent to an opening between the passage and chamber. The angled plane of the first contact face may widen the anchorage field (i.e. contact surface area) of a compression load applied by the anchor block. This may have the effect of further improving the reliability and general performance of the connector.

In an embodiment, the anchor block may be symmetrical across the tendon longitudinal axis. The first contact face may thus comprise respective angled planes located on opposite sides of the tendon longitudinal axis. In an embodiment of the anchor block, the angling of the angled plane may be in the range of <NUM>-<NUM> degrees, and optimally <NUM>-<NUM> degrees, to the tendon longitudinal axis. As described in detail later, such an angle range can widen the resistance field outside of the connector so that it is not so focused in the surrounding concrete. When the first contact surface has an angled plane in this range, the resistance field of compression may be increased when compared to higher or lower angles. In an embodiment, the enlarged formation may be adapted such that a tensile force applied the tendon can be transferred via the enlarged formation to the housing as a compression force.

In an embodiment, the anchor block may further comprise a second contact face that is substantially flat and that extends orthogonally with respect to a longitudinal axis of the tendon. The second contact face may be adapted to oppose so as to engage an interior facing rear wall of the chamber located on an opposite chamber side to the opening. For example, prior to grouting/locking, and when the anchor block is at a rearmost position within the chamber, it may thus slide laterally along the rear wall of the chamber in correspondence to a lateral sideways movement of the tendon within the seal.

In an embodiment, grout may be located, in use, within the chamber to surround and capture the enlarged formation such that a lateral and/or longitudinal movement of the second surface relative to the first surface is restricted. Typically, the grout is employed once the first and second surfaces (e.g. sections, slabs or floor plates) have sufficiently settled/cured/come to rest. In an embodiment, the housing may have an inlet configured such that a grout can flow therethrough (e.g. be injected therethrough) into the housing, and an outlet configured such that a grout can flow therethrough out of the housing. In an embodiment, at least one of the inlet and/or the outlet are arranged at an upper portion of the chamber.

In an embodiment, the grout that is introduced into the chamber can comprise a dense fluid such as a mixture of water, cement, and sand. In an embodiment, the grout may be the same as the concrete used for forming the section/slab/plate, or it have a different formulation and consistency.

Also disclosed is a connector system (not part of the invention) for use in forming a joint between a first surface and a second surface. The connector system comprises a housing and a tendon. When the tendon is installed within the housing, a first portion of the tendon is retained within the housing, and a second portion of the tendon protrudes from the housing through a seal. The seal is configured to sealably cover an open end of the housing such that the tendon can move through the seal and laterally sideways across the open end together with at least a portion of the seal. Furthermore, the tendon first portion has a configuration such that the tendon first portion cannot pass out of the housing via the seal. The connector system may in some embodiments comprise various of the features of the connector as set forth above.

Also disclosed is a method (not part of the invention) of installing a connector for use in forming a joint between a first surface and a second surface. The connector comprises a housing and a tendon. A seal is configured to sealably cover an open end of the housing such that, when installed and prior to locking, the tendon can move through the seal and laterally sideways across the open end together with at least a portion of the seal. The method comprises:.

The method need not be performed strictly in this order. For example, the tendon can become embedded into the cured second surface prior to being inserted into the housing (and prior to the housing being embedded into the cured first surface). Further, the housing and tendon can be assembled through the formwork and the surfaces cured simultaneously.

The method may further comprise allowing the first and second surfaces to move laterally and/or longitudinally relative to one another (e.g. up until the first and second surfaces have each sufficiently settled/cured/come to rest). During such movement, the housing is captive to and thus moved by the first surface, and the portion of the tendon that protrudes from the housing through the seal is captive to and thus moved by the second surface. Because the tendon is not fully fixed against movement with respect to the housing, a seal may therefore be employed that is more robust, with improved reliability and longevity.

In an embodiment, the method may further comprise locking the connector such that the first and second surfaces are restricted from moving laterally and/or longitudinally relative to one another (e.g. once the first and second surfaces have each sufficiently settled/cured/come to rest). The connector used in the method may comprise various of the features of the connector as set forth above.

Various forms of the connector, system and method will now be described, by way of example only, with reference to the accompanying drawings in which:.

In the following detailed description, reference is made to accompanying drawings which form a part of the detailed description. The illustrative embodiments described in the detailed description, depicted in the drawings and defined in the claims, are not intended to be limiting. Other embodiments may be utilised, and other changes may be made without departing from the spirit or scope of the subject matter presented. It will be readily understood that the aspects of the present disclosure, as generally described herein and illustrated in the drawings can be arranged, substituted, combined, separated and designed in a wide variety of different configurations, all of which are contemplated in this disclosure.

Referring generally to the drawings, an improved temporary movement connector is shown in two forms, namely, a connector <NUM>, as illustrated variously in <FIG>, and a connector <NUM>', as illustrated variously in <FIG>. The connector <NUM>,<NUM>' comprises a housing <NUM>,<NUM>' and a tendon in the form of a dowel bar <NUM>. The temporary movement connector is employed to join and then to transfer forces that arise as a result of differential movement between adjacent sections/slabs/plates as they settle and cure and to transfer long term forces after locking. The connector is typically though not exclusively employed in the construction of a multi-storey building that has large floor spans.

In use, as illustrated in <FIG>, the housing <NUM> can become embedded into in a first surface <NUM> (e.g. a first slab) as it cures, whilst the dowel <NUM> can become embedded into an adjacent second surface <NUM> (e.g. a second adjacent slab) as it cures. The first <NUM> and second <NUM> surfaces can take the form of sections, slabs, or plates that may be formed adjacent to one-another, with the connector <NUM> acting as the joint therebetween. The surfaces <NUM>,<NUM> may be any two adjacent surfaces that may require post-tensioning. For example, in some applications, the first <NUM> and second <NUM> surface can be two adjacent floor slabs. In other applications the first <NUM> and second <NUM> surfaces can be a floor slab located adjacent to a vertical wall slab respectively.

Prior to locking the connector <NUM>, typically by filling the housing <NUM> with grout, the connector <NUM> can act as an adjustable joint, whereby the housing <NUM> and tendon <NUM> are able to move relative to one another laterally and or longitudinally (within the predesigned structural constraints of the connector <NUM>), thus allowing for a temporary release of the restraining effects of the surfaces <NUM>,<NUM> relative to one another. This may assist in ensuring that the maximum amount of post-tensioning pre-compression forces or shrinkage or creep forces can be transferred into the surfaces <NUM>,<NUM> before they are locked together.

In the embodiment illustrated in <FIG>, the housing <NUM> is adapted to form a hollow shaft between a housing open end <NUM> and a housing anchor end <NUM>. As best seen in <FIG> and <FIG>, a passage <NUM> extends between a seal <NUM> (i.e. that is located at the open end <NUM> of the housing <NUM>) and a chamber <NUM> located at the anchor end <NUM> of the housing <NUM>. The housing <NUM> can be made of a metallic material, such as steel, which may improve the fire resistance of the connector <NUM>. Metallic materials may also improve the longevity of the connector <NUM> and reduce instances of failure during installation and post-tensioning of the connector <NUM>.

The passage <NUM> has a generally rectilinear cross-section therealong, although in other embodiments the cross-section may be formed into other suitable shapes such as circular, ovular, or square. As best illustrated in <FIG>, the passage <NUM> can have an internal cross-sectional height H1 that corresponds to the diameter of the dowel <NUM>. In use, a dowel <NUM> that has been inserted through the passage <NUM> may thus be substantially restrained from moving up or down in a vertical direction. The passage <NUM> also has an internal cross-sectional width W1 that can be adapted to correspond with the desired range of lateral movement of the dowel <NUM> with respect to the housing <NUM>, prior to locking. For example, in an embodiment where the joint is to be allowed a lateral tolerance of <NUM> to either side of a central longitudinal axis A-A of the connector <NUM>; the total internal width W of the passage <NUM> can be the diameter of the dowel <NUM> plus <NUM>. A person skilled in the art would appreciate that the connector <NUM> is scalable and can be manufactured to any size to suit the specific constraints for the joint as specified by a structural engineer or similar person skilled in the art.

The seal <NUM> comprises a sealing element in the form of a sealing plate <NUM> that is captively retained within a sleeve <NUM>, the sleeve <NUM> being mounted at the open end <NUM> of the housing <NUM>. As set forth above, the seal <NUM> may solely comprise the sealing plate <NUM>, or the seal may be defined by a combination of the sealing plate <NUM> and sleeve <NUM>, etc..

The sleeve <NUM>, as illustrated in <FIG> and <FIG>, can comprise two metallic plates that, when joined together (e.g. by welding), are arranged such that a contained pocket <NUM> is formed therebetween. To assist with fastening the housing <NUM> to formwork prior to curing of the first surface <NUM>, such as vertical formwork <NUM> as seen in <FIG>, the sleeve <NUM> can be provided with one or more holes <NUM> therethrough that are spaced around the distal edges of the sleeve <NUM>. Thus, a suitable formwork fastener can be driven through each such hole <NUM>.

The sleeve <NUM> is arranged to have a window <NUM> formed in its external face such that the sealing plate <NUM> is exposed therethrough. The window <NUM> can be substantially rectangular in shape, having a vertical height sufficient for the tendon to protrude therethrough and a lateral width that generally corresponds to the desired range of lateral movement of the dowel <NUM>.

The sealing plate <NUM> is flat and has an external profile that closely corresponds to the inner walls of the pocket <NUM>, but such that the plate is configured to be laterally slideable within the pocket. The sealing plate <NUM> has a lateral width and vertical height that is larger than that of the window <NUM> such that the sealing plate <NUM> overlaps with the internal faces of the sleeve <NUM> (i.e. that face into the pocket <NUM>).

A semisolid or pseudo-plastic fluid such as grease can be applied to the external surface of sealing plate <NUM> such that it forms a barrier across any gaps that may form between the sealing plate <NUM> and the internal faces of pocket <NUM> of sleeve <NUM>. The barrier of semisolid or pseudo-plastic fluid can thus prevent grout and/or cementitious material from flowing through the seal <NUM>. The semisolid or pseudo-plastic fluid can also facilitate the lateral sliding of plate <NUM> within the pocket <NUM>.

The sealing plate <NUM> can be formed to have a height that generally corresponds to the height of the pocket <NUM> such that the sealing element <NUM> cannot slide up or down vertically within the pocket <NUM> but is still able to slide laterally within and along the width of the pocket <NUM>. As with the passage <NUM>, the relative widths of the pocket <NUM> and sealing plate <NUM> can be designed to allow the sealing plate <NUM> to slide a distance laterally sideways within the pocket <NUM> of sleeve <NUM>, with the distance corresponding to the desired range of lateral movement of the dowel <NUM> with respect to the housing <NUM> (i.e. prior to locking of the tendon within the housing). For example, in an embodiment where the joint is to be allowed a lateral tolerance of <NUM> to either side of a central longitudinal axis A-A of the connector <NUM> - the distance between the internal walls <NUM> of the pocket <NUM> and the side walls <NUM> of the sealing plate <NUM> when centred can be <NUM> on either side of the sealing plate <NUM>.

An aperture <NUM> can be centrally located in the sealing plate <NUM>, the aperture <NUM> being aligned vertically with the central longitudinal axis A-A such that, in use, a dowel <NUM> can move therethrough and into the passage <NUM> of the housing <NUM>. The aperture <NUM> can be dimensioned to substantially correspond to the diameter of the dowel <NUM> so as to sealably engage the dowel <NUM> in use, whilst still permitting the dowel <NUM> to slide back-and-forth therethrough. The aperture <NUM> can comprise an O-ring <NUM> around its perimeter that may assist with creating a close seal between the sealing plate <NUM> and the dowel <NUM>.

In some embodiments, the O-ring <NUM> can be formed from a deformable yet resilient material that contrasts with the generally stiff/rigid material of the sealing plate <NUM>. For example, the O-ring <NUM> can be formed from an elastomeric material such as a hard rubber and the sealing element <NUM> from a metal. In some embodiments, both the O-ring <NUM> and the sealing plate <NUM> can be made from a generally stiff/rigid material that is substantially inelastic, such as a metal or a carbon fibre/composite, with the O-ring toleranced to seal against the dowel <NUM> such that grout cannot pass therebetween, yet without restricting the dowel <NUM> from being able to move longitudinally therethrough. In some embodiments, the sealing plate <NUM> can be configured to seal directly against the dowel <NUM>. The passage <NUM>, the aperture <NUM>, and the sealing plate <NUM> in pocket <NUM> can, in combination, maintain the longitudinal axis of the dowel <NUM> to remain aligned with or substantially parallel to the central longitudinal axis A-A in use.

Thus, the seal <NUM> is configured to sealably cover the open end <NUM> of the housing <NUM> and to seal around the dowel <NUM>. In use, the tendon first portion <NUM> is inserted through the seal <NUM> such that the tendon second portion <NUM> protrudes from the housing <NUM>. In use, the dowel <NUM> can engage the aperture <NUM> so as to move the sealing plate <NUM> laterally sideways across the open end <NUM> of the housing within the pocket <NUM> of sleeve <NUM>. The dowel <NUM> remains free to be moved longitudinally through the aperture <NUM> of the seal <NUM> without compromising the sealed engagement.

As set forth herein, in use, the housing <NUM> can become embedded into a curing first surface <NUM>, with a portion of the dowel <NUM> protruding therefrom so as to become embedded into an adjacent, curing second surface <NUM>. Thus, because the dowel <NUM> can move longitudinally through the seal <NUM>, and because the seal <NUM> does not need to bridge between components of the housing <NUM> that are embedded into the two adjacent surfaces <NUM>,<NUM>, the seal <NUM> is able to be constructed in a more robust and reliable format. For example, the seal <NUM> can be primarily constructed of high strength and durable materials, such as a metal, metal alloy, composite, etc., thereby allowing the dowel <NUM> to bear against and slide the sealing plate <NUM> of seal <NUM> laterally across the open end <NUM> as required, whilst still sealably engaging the dowel <NUM> when it slides longitudinally through the aperture <NUM>.

Whilst the chamber <NUM> can be located at any position along the passage <NUM>, in the embodiment shown in <FIG>, the chamber <NUM> is located at the anchor end <NUM> of the passage <NUM>, so as to be at a housing end that is opposite to the seal <NUM>. Thus, in use, the dowel <NUM> can extend fully through the passage <NUM> from the chamber <NUM> before protruding through the seal <NUM>. A long overlap between the tendon and housing can assist in strengthening the joint. The longer overlap between the tendon and housing can also assist in reducing vertical pivoting of the tendon about the seal <NUM>.

In the embodiments illustrated, at the point where the chamber <NUM> is connected to the passage <NUM>, the chamber <NUM> has a greater internal cross-sectional height H2 and internal cross-sectional width W2 than the internal cross-sectional height H1 and internal cross-sectional width W1 of the passage <NUM>. The chamber <NUM> is thus adapted to retain an anchor block <NUM> therein, whereby the relative cross-sectional dimensions of the passage <NUM> and the chamber <NUM>, and the relative size of the anchor block <NUM>, work together to prevent the anchor block <NUM> from moving wholly out of the chamber <NUM> and passing into and through the passage <NUM>.

Typically, the anchor block <NUM> is an enlarged formation that is dimensioned to be moveable, in use, in a lateral and longitudinal direction relative to the central longitudinal axis A-A, within the chamber <NUM>. When the tendon first portion <NUM> is inserted within the chamber, a first end of the dowel <NUM> can be connected to the anchor block <NUM>. For example, as seen in <FIG>, <FIG> and <FIG>, the tendon first portion <NUM> can be threaded <NUM> so as to be screwed into a corresponding threaded hole <NUM> formed in the anchor block <NUM>. The tendon first portion <NUM> thus becomes configured such that it cannot be removed from the chamber <NUM>, and thus from the housing <NUM> via the seal <NUM>.

The internal walls of the chamber <NUM> and the corresponding contact surfaces of the anchor block <NUM> are sized and angled to oppose and so as to engage each other. The anchor block <NUM> can be a solid block that is substantially flat along the upper, lower, side and rear contact surfaces, with these surfaces opposing so as to engage corresponding substantially flat interior facing walls of the chamber <NUM>. For example, the anchor block can have a rear facing contact surface <NUM> that is substantially flat and that extends substantially orthogonally with respect to the central longitudinal axis A-A (and to the longitudinal axis of the dowel <NUM>). The rear facing contact surface <NUM> of the anchor block <NUM> can thus move or slide laterally along the substantially flat interior facing rear wall <NUM> of the chamber <NUM>. Thus, the anchor block <NUM> is not impeded from moving transversely along the internal walls of the chamber <NUM>. The anchor block <NUM> can have a vertical height that generally corresponds with the internal vertical height of the chamber <NUM>. In use, a dowel <NUM> that has the anchor block <NUM> mounted to its threaded end <NUM> can thereby be substantially restrained from moving in a vertical direction relative to the housing <NUM>.

The chamber <NUM> and anchor block <NUM> can be dimensioned to have relative lateral and longitudinal lengths between the opposing walls and contact surfaces, such that the range of lateral and longitudinal movement can be constrained to be within an allowable tolerance. For example, as illustrated by <FIG>, the lateral width W3 of the anchor block <NUM> relative to the internal lateral width W4 of the chamber <NUM> can be adapted to correspond to the desired range of lateral movement of the dowel <NUM> with respect to the housing <NUM>, prior to locking. For example, where the joint is to be allowed a lateral tolerance of <NUM> to either side of a central longitudinal axis A-A of the connector <NUM>; the internal lateral width W4 of the chamber <NUM> can be <NUM> larger than the lateral width W3 of the anchor block <NUM>. Likewise, as seen in <FIG>, the longitudinal depth D1 of the anchor block <NUM> relative to the internal longitudinal depth D2 of the chamber <NUM> can be adapted to correspond with the desired range of longitudinal movement of the dowel <NUM> with respect to the housing <NUM> prior to locking. For example, where the joint is to be allowed a longitudinal tolerance of <NUM> relative to a central lateral axis C-C passing through the chamber; the internal longitudinal depth D2 of the chamber <NUM> can be <NUM> larger than the longitudinal depth D1 of the anchor block <NUM>. A person skilled in the art would appreciate that the connector <NUM> is scalable and can be manufactured to any size to suit the specific constraints for the joint as specified by a structural engineer or similar person skilled in the art.

On either side of the threaded hole <NUM> and the longitudinal axis through the dowel <NUM>, the anchor block <NUM> is symmetrical and can have angled contact surfaces <NUM> that form a plane that is angled with respect to the longitudinal axis of the dowel <NUM>. The angling of the angled plane can be in the range of <NUM>-<NUM>, optimally <NUM>-<NUM>, degrees to the longitudinal axis of the dowel <NUM>. The angled plane of the angled contact surfaces <NUM> may widen the resistance compression field area arising from a compression load applied by the anchor block <NUM> when it has been locked against movement due to grout having been introduced within to fill the chamber <NUM>. When the first contact surface has an angled plane in this range, the resistance field of compression outside of the connector can be increased when compared to higher or lower angles. This can further improve the reliability and general performance of the connector <NUM>. The corresponding angled walls <NUM> of the chamber <NUM> that are located adjacent the passage <NUM> can be angled in the range of <NUM>-<NUM> degrees to the central longitudinal axis A-A.

As seen in <FIG>, by way of example, a tension load T on the dowel <NUM> may thus be converted into a compression load that is dispersed between the anchor block <NUM>, the surrounding grout (or cementitious material) <NUM>, the angled chamber wall <NUM> and the surrounding surface (e.g. floor/wall slab) in which connector is embedded. For example, in embodiments when the anchor block <NUM> and chamber <NUM> are made from steel, the tensile load applied to the dowel <NUM> can be initially converted into a compression force via the angled contact surfaces <NUM> against the surrounding grout <NUM> which in turn is compressed against the inside of the angled chamber wall <NUM>. The compression load C is then further distributed out of the chamber <NUM> by compression of the exterior surface of the angled chamber wall <NUM> against the surrounding surface (i.e. the surrounding concrete slab material). <FIG> illustrates how an angled plane of the angled contact surfaces <NUM> can thus act to widen the resistance field of a compression load C. By converting a majority of the tensile load into a compressive load the likelihood of failure of the connector may be reduced, as grout (and cementitious material in general) has increased performance when under compressive loads than when under tensile loads.

The chamber <NUM> can also have inlet and outlet connection points <NUM> arranged thereon to allow grout to flow into and out of the chamber <NUM>. Grout that flows into the chamber <NUM> can flow therefrom into the passage <NUM> so as to fill the housing <NUM>, and continues to flow until the grout overflows from the outlet. When the housing is substantially filled with grout, the grout surrounds and, when cured, captures the anchor block <NUM> as well as the shaft of the dowel <NUM> that is located inside the housing <NUM>, such that a lateral and/or longitudinal movement of the dowel <NUM> relative to the housing <NUM> is now restricted/prevented. The connection points <NUM> are arranged at an upper portion of the chamber <NUM>. Thus, once the housing <NUM> has been filled with grout, any excess grout flow outs of the housing <NUM> through the upper outlet connection point <NUM>, thereby indicating that the housing is now substantially filled with grout.

A nut <NUM> and washer <NUM> can be fastened to the threaded end of the tendon second portion <NUM>. Thus, the overall configuration of connector <NUM> is such that seal <NUM> does not need to bridge between the two adjacent surfaces <NUM>,<NUM>, because the tendon second portion <NUM> is configured such that in use it can be captively secured within the second surface <NUM> on its own and independently of the seal (i.e. in contradistinction to prior art arrangements, the tendon second portion <NUM> is not fixed to any part of the housing that moves with the dowel <NUM> in both the lateral and longitudinal directions).

A method of installing the connector <NUM> to form a joint between a first surface <NUM> and a second surface <NUM>, will now be described with reference to <FIG>. In the illustrated embodiment, the first <NUM> and second <NUM> surface are two adjacent floor slabs, however, a person skilled in the art would understand that the same method can be applied to any two adjacent slabs including, for example, a floor slab adjacent a vertical wall slab.

Prior to installation of the components of the connector <NUM>, formwork <NUM>,<NUM> is erected to define the adjacent faces of the surfaces being joined (this formwork is schematically depicted in <FIG> and comprises horizontal plate <NUM> and vertical plate <NUM>).

The housing <NUM> is then installed by fastening the sleeve <NUM> of seal <NUM> to the vertical formwork <NUM> through the fastening holes <NUM> (see <FIG>). At this stage of the method, the dowel <NUM> has not yet been inserted into the housing <NUM> and, as such, the opposing side of the vertical formwork <NUM> does not yet comprise any components of the connector <NUM> (see <FIG>). However, the chamber <NUM> of housing <NUM> has been "preloaded" with the yet-to-be-secured anchor block <NUM> positioned therein, ready to be later-connected to the dowel <NUM>.

Furthermore, it will be seen that the seal <NUM> does not bridge across from the first surface <NUM> to the second surface <NUM>. Thus, the seal <NUM> does not need to protrude through the vertical formwork <NUM> (i.e. it can simply be mounted to one side of plate <NUM>). Further, the plate-facing side of the seal <NUM> need not be covered by an additional component to protect against the ingress of grout into the housing <NUM> (i.e. see <FIG>).

The first surface <NUM> is then poured along a first side of the removable vertical formwork plate <NUM> (see <FIG>). Although not depicted, conduits are connected to the inlet and outlet connection points <NUM> so that grout can later be pumped into the chamber <NUM> of housing <NUM>. It would also be well understood by one skilled in the art that further formwork components that are typically used when forming a cementitious surface (e.g. steel mesh, saddles, ties, sides, etc.) are also installed prior to pouring the surfaces <NUM>, <NUM>.

Once the first surface <NUM> has cured sufficiently, the vertical formwork <NUM> is removed to expose the seal <NUM> (see <FIG>). It will also be seen that the outer facing surface of the seal <NUM> is substantially contiguous with the face of the first surface into which the housing <NUM> has become embedded.

The dowel <NUM> can now be installed into the housing <NUM>. Installation of the tendon includes inserting the first portion <NUM> of the dowel <NUM> through the aperture <NUM> of the sealing plate <NUM>, leaving the tendon second portion <NUM> to protrude from the housing <NUM> (see <FIG>). Once inserted into the housing <NUM>, the tendon first portion can be connected to the anchor block <NUM>. In this regard, the threaded end <NUM> of tendon first portion <NUM> can be screwed into the corresponding threaded hole <NUM> of the anchor block <NUM>. Thus, the anchor block <NUM> now captively retains the tendon first portion <NUM> within the housing (<FIG>).

The second surface <NUM> is then able to be poured around the tendon second portion <NUM> (see <FIG>). Initially, the second surface <NUM> is located adjacent to the first surface <NUM> (<FIG>). However, once the surfaces are sufficiently cured, and with the formwork removed (<FIG>), the two surfaces are then allowed to move laterally and/or longitudinally relative to one another (i.e. as the surfaces progressively cure, settle and harden). During the usual, resultant differential movement that occurs between the surfaces <NUM>, <NUM>, the housing <NUM> remains captive within and is thus moved by and with the first surface <NUM>, whilst the tendon second portion <NUM> remains captive within and is thus moved by and with the second surface. The connector <NUM> is designed to accommodate all such movement, without breaking the joint between surfaces <NUM>, <NUM> and thus supporting them throughout curing.

When the surfaces <NUM>, <NUM> have sufficiently cured such that minimal or no further differential movement between them occurs, the connector <NUM> is locked by pumping grout into the housing <NUM> through the inlet connection point <NUM> located above the chamber <NUM>, with excess grout then flowing out of the outlet connection point <NUM>. The excess grout can also be used to fill up any voids left by the grout connecting conduits or passages formed within the surface <NUM>. Once the grout has cured, the connector <NUM> is locked whereby the dowel <NUM> and housing <NUM> and thus the surfaces <NUM>, <NUM> are prevented from any further movement relative to one another.

In a variation of the above described installation method, the dowel <NUM> can be cured into the second surface <NUM> prior to being inserted into the housing <NUM> (and prior to the housing <NUM> being embedded into the first surface <NUM>). In another variation of the above described installation method, the housing <NUM> and dowel <NUM> can be pre-assembled through the vertical formwork plate <NUM> and the surfaces <NUM>, <NUM> can then be poured simultaneously.

In a further variation, illustrated in <FIG>, and in which like reference numbers are used to denote similar or like parts to those previously described, a connector <NUM>' is shown in which the housing <NUM>' can be formed as multiple components and/or using a plurality of materials.

For example, the in-use rearward portion 10a' of the housing <NUM>', comprising the chamber <NUM>' and a rearward portion of the passage 40a, can be formed as a separate component from the in-use forward portion 10b' of the housing <NUM>', comprising a forward portion of the passage 40b and the seal <NUM>'. The in-use rearward portion 10a' can further be formed to comprise a lower shell <NUM>' and an upper shell <NUM>', where each shell <NUM>', <NUM>' can be formed by injection moulding using a thermoplastic polymer such as ABS. The two shells <NUM>', <NUM>' can be friction welded together along respective lips <NUM>' so as to form together the in-use rearward portion 10a' of the housing <NUM>'. The lips <NUM>' are formed during the injection moulding process along the edge where the two shells <NUM>', <NUM>' abut in use.

By contrast, the in-use forward portion 10b' can be formed using steel components, for example using stainless steel or mild steel. The open end 42b of the passage 40b of the in-use forward portion 10b' can be slidably received within the open end of the passage 40a of the rearward portion 10a'. Once slidably received, the passage 40a of the rearward portion 10a' can be dimensioned relative to the passage 40b so as to disallow any concrete cement fines from ingressing therebetween during casting of the surface <NUM>. In some embodiments, open end 42b can be press-fit within the rearward portion 10a' so as to be retained thereat. In some embodiments, the passage 40a of the rearward portion 10a' can overlap with the passage 40b sufficiently so as to disallow any concrete cement fines from ingressing therebetween during casting of the surface <NUM>. An inwardly projecting flange <NUM>' is adapted around the interior facing walls of the passage 40a of the rearward portion 10a'. The flange <NUM>' is configured so as to abut the foremost edge of the open end 42b of the passage 40b of the in-use forward portion 10b', whereby the in-use forward portion 10b' is prevented from sliding any further within the passage 40a of the rearward portion 10a'.

At least one of the lower shell <NUM>' and/or upper shell <NUM>' of the chamber <NUM>' can comprise anchor block tabs <NUM>' (see <FIG>, <FIG>). The anchor block tabs <NUM>' project inwardly from the respective lower or upper shell <NUM>'<NUM>' surface so as to interact with a portion of the contact surfaces <NUM> and/or side surfaces <NUM> of the anchor block <NUM>. Prior to displacement of the anchor block <NUM> during curing, the anchor block tabs <NUM>' support the anchor block <NUM> in a substantially central location within the chamber <NUM>'. In some embodiments, as shown in <FIG>, the anchor block tabs <NUM>' can support the anchor block <NUM> substantially centrally laterally, and rearward against the interior facing rear wall <NUM> of the chamber <NUM>'. In some embodiments, not shown, the anchor block tabs <NUM>' can support the anchor block <NUM> substantially centrally laterally, and substantially centrally longitudinally within the chamber <NUM>' so as to provide space in all directions within which the anchor block <NUM> can move. This can assist with aligning the respective threaded portions <NUM>, <NUM> of the dowel <NUM> and the anchor block <NUM> when the dowel is inserted into the housing <NUM>' via the seal <NUM>. In use, when the dowel <NUM> moves laterally and or longitudinally relative to the housing <NUM>', the force applied by the anchor block <NUM> at the tendon first portion <NUM> against the anchor block tabs <NUM>' can cause the anchor block tabs <NUM>' to fail, for example, to break off, whereby the anchor block <NUM> is released from the restraining effects of the anchor block tabs <NUM>'.

As best seen in <FIG>, the seal <NUM>' comprises a sealing element in the form of a sealing plate <NUM>' that is captively retained within a sleeve <NUM>', the sleeve <NUM>' being mounted at the open end <NUM> of the in-use forward portion 10b'. The sleeve <NUM>' comprises a backing plate 54a', a spacer plate 54b' and a front plate 54c'. The forward portion of the passage 40b and the backing plate 54a' can be welded together on the rear side of the backing plate 54a'. The spacer plate 54b' and the front plate 54c' can be welded onto the forward side of the backing plate 54a', whereby a contained pocket (not shown) is formed therebetween. The sealing plate <NUM>' can be formed to have a height that generally corresponds to the height of the pocket <NUM>' such that the sealing element <NUM>' cannot slide up or down vertically within the pocket <NUM>' but is still able to slide laterally within and along the width of the pocket <NUM>'. As best seen in <FIG>, <FIG> and <FIG>, the seal <NUM>' can be welded on all sides <NUM>' of the sleeve <NUM>'. This can improve the manufacturability of the seal <NUM>'.

The aperture <NUM>' of the sealing plate <NUM>' can comprise an O-ring <NUM>' around its perimeter that can assist with creating a close seal between the sealing plate <NUM>' and the dowel <NUM> (see <FIG>). The O-ring <NUM>' can be retained adjacent the aperture <NUM>' by a weld plate <NUM>'. The weld plate <NUM>' comprises a plurality of tabs <NUM>' that facilitate welding of the weld plate <NUM>' to the sealing plate <NUM>' and can reduce the likelihood of the O-ring <NUM>' being damaged during the manufacturing process. In some embodiments, the O-ring <NUM>' can be formed from a compressed or toughened elastomeric material such as a hard rubber. The O-ring <NUM>' can be toleranced to seal against the dowel <NUM> such that grout cannot pass therebetween, yet without restricting the dowel <NUM> from being able to move longitudinally therethrough.

As discussed above, a tension load T on the dowel <NUM> may be converted into a compression load that is dispersed between the anchor block <NUM>, the surrounding grout (or cementitious material) <NUM>, the angled chamber wall <NUM> and the surrounding surface (e.g. floor/wall slab) in which connector <NUM>' is embedded. For example, in embodiments such as in <FIG>, where the chamber <NUM>' is made primarily using an injection moulded thermoplastic polymer, each of the angled chamber walls <NUM> can comprise a steel plate <NUM>'. As best seen in <FIG>, each steel plate <NUM>' can be retained within a window-frame-like groove <NUM>' formed in each of the angled chamber walls <NUM> on either side of the chamber <NUM>'. Thus, tensile loads applied to the dowel <NUM> can be converted into a compression force via the angled contact surfaces <NUM> of the anchor block <NUM> against the surrounding grout <NUM> which in turn is compressed against the inside of the steel plate <NUM>' configured at the angled chamber wall <NUM>. The compression load C can then be further distributed out of the chamber <NUM>' by compression of the exterior surface of the steel plate <NUM>' against the surrounding surface (i.e. the surrounding concrete slab material). By forming the chamber <NUM>' primarily using injection moulded thermoplastic polymer , the housing <NUM>' can advantageously be fabricated more cheaply, and with a more complex shape, whilst retaining the design and functionality requirements that are necessary for transferring the forces that act on the dowel <NUM> and anchor block <NUM> via the surrounding grout <NUM> to the steel plates <NUM>' and outwards into the surrounding surface <NUM>.

In a further variation, illustrated in <FIG>, the anchor block <NUM>' can be formed as a plate having symmetrical angled contact surfaces <NUM>' that are bent relative to the forward contact surface <NUM>' on either side of a threaded hole <NUM>' so as to form planes that are angled with respect to the longitudinal axis of the dowel <NUM>. The weight of the anchor block <NUM>' can thus be reduced. As above, the angling of the angled plane can be in the range of <NUM>-<NUM>, optimally <NUM>-<NUM>, degrees to the longitudinal axis of the dowel <NUM>. The internal walls of the chamber <NUM> and the corresponding contact surfaces of the anchor block <NUM>' are sized and angled to oppose and so as to engage each other. Furthermore, the anchor block <NUM>' is dimensioned to be moveable, in use, in a lateral and longitudinal direction relative to the central longitudinal axis A-A, within the chamber <NUM>.

In use, the rear surface of the threaded hole <NUM>' forms the rear facing contact surface <NUM>' that is substantially flat and that extends substantially orthogonally with respect to the central longitudinal axis A-A (and to the longitudinal axis of the dowel <NUM>). Thus, when the tendon first portion <NUM> is inserted within the chamber <NUM>, a first end of the dowel <NUM> can be connected to the anchor block <NUM>' through the threaded hole <NUM>' that extends from the forward contact surface <NUM>' towards the rear facing contact surface <NUM>'. In use, the relative dimensions of the anchor block <NUM>' and the cross-sectional dimensions of the passage <NUM> and the chamber <NUM> work together to limit the movement of the anchor block <NUM>' within the chamber <NUM>.

It would also be well understood by one skilled in the art that the anchor block may take any of a plurality of shapes or forms, and yet still be able to function within the scope of the present disclosure as described above.

In yet a further variation, the aperture <NUM>" of the sealing plate <NUM>" can be formed as a threaded window that is configured to receive a cylindrical sealing ring <NUM>" (see <FIG>). The sealing ring <NUM>" can be screwed into the threaded aperture <NUM>". In some embodiments, the interior surface of the cylindrical sealing ring <NUM>" can comprise an O-ring like seal <NUM>" that can be toleranced to seal against the dowel <NUM> such that grout cannot pass therebetween, yet without restricting the dowel <NUM> from being able to move longitudinally therethrough.

In use, the rearward projection <NUM>" of the threaded aperture <NUM>" and sealing ring <NUM>" are adapted to fit within the open end of the passage. In some embodiments, not shown, the rearward projection <NUM>" can act as a stop. Thus, as the sealing plate <NUM>" slides laterally within the seal in use, the rearward projection <NUM>" can abut the interior side walls of the passage so as to prevent the sealing plate <NUM>" from any further lateral movement in that direction.

In some embodiments, the sealing function (e.g. that can be performed by the O-ring <NUM>, <NUM>', <NUM>") can be instead performed by use of grease, bentonite or any suitable material that swells upon contact with water or grout. In some embodiments, a contact surface comprising a compressed rubber exterior can allow sufficient sliding whilst simultaneously performing the sealing function. In some embodiments, compressed rubber can be suitable for facilitating sufficient sliding in the between the sealing plate <NUM> and the internal faces of pocket <NUM> of sleeve <NUM>.

Other variations and modifications may be made to the parts previously described without departing from the spirit or ambit of the disclosure.

Claim 1:
A connector (<NUM>, <NUM>') for use in forming a joint between a first surface (<NUM>) in the form of a cast section, slab or plate and a second surface (<NUM>) in the form of a cast section, slab or plate, the connector (<NUM>, <NUM>') comprising a housing (<NUM>, <NUM>') and a tendon (<NUM>);
a portion of the tendon (<NUM>) protruding from the housing (<NUM>, <NUM>') through a seal (<NUM>), the seal (<NUM>) being configured to sealably cover an open end (<NUM>) of the housing (<NUM>, <NUM>') such that the tendon (<NUM>) can move through the seal (<NUM>) and laterally sideways across the open end (<NUM>) together with at least a portion of the seal (<NUM>),
wherein the seal (<NUM>) comprises a sealing element (<NUM>) that is captively retained within a sleeve (<NUM>), characterized by the sleeve (<NUM>) being affixed at the open end (<NUM>) of the housing (<NUM>, <NUM>'), such that the lateral movement of the tendon (<NUM>) causes the sealing element (<NUM>) to be laterally displaced within and relative to the sleeve (<NUM>),
wherein the sealing element (<NUM>) comprises a flat plate that is configured to move laterally with the tendon (<NUM>) in use.