Patent Description:
Many structures are built using concrete, including, for instance, buildings, parking structures, apartments, condominiums, hotels, mixed-use structures, casinos, hospitals, medical buildings, government buildings, research/academic institutions, industrial buildings, malls, bridges, pavement, tanks, reservoirs, silos, foundations, sports courts, and other structures.

The concrete may be poured into a concrete form. The concrete form may be a form or mold to give shape to the concrete as the concrete sets or hardens thus forming a concrete member.

Prestressed concrete is structural concrete in which internal stresses are introduced to reduce potential tensile stresses in the concrete resulting from applied loads; prestressing may be accomplished by post-tensioned prestressing or pre-tensioned prestressing. In post-tensioned prestressing, a post-tensioning tendon embedded in the concrete is tensioned after the concrete has attained a specified strength. A post-tensioning tendon may include for example and without limitation, anchorages, the tension member, and sheathes or ducts.

A post-tensioning tendon generally includes an anchorage at each end. The tension member is fixedly coupled to a fixed anchor positioned at one end of the post-tensioning tendon, sometimes referred to as the "fixed-end" or "dead end" anchor, and is stressed at the other anchor, sometimes referred to as the "stressing-end" or "live end" anchor.

The tension member may be constructed of a material that is suitable for post-tensioning, such as, for example, reinforcing steel or composite material in the form of single or multi-strand cable. A post-tensioning tension member is typically provided in a protective sheath. The sheath may be polymeric and may contain a protective fluid, such as grease, in addition to the tension member. The purpose of the sheath and protective fluid, if present, is to inhibit air, water, and other corrosive substances from contacting the tension member.

The tension member is stressed by pulling the tension member through the stressing anchor; when the pulling force is released, the anchors grip the tension member and retain the tension member in tension. In some instances, the anchors grip the tension member using wedges, so that the gripping force increases when the tension on the tension member increases.

<CIT> discloses a splice chuck for use in a post-tension anchor system.

The present invention is set out in the claims. In one aspect of the present invention, according to claim <NUM>, there is provided a sheathing repair assembly for a tension member of a post-tensioning tendon, the tension member comprising a strand and a sheathing layer, the sheathing repair assembly comprising:.

In one aspect of the present invention, according to claim <NUM>, there is provided a method for repairing an unsheathed portion of a tension member, the tension member comprising a strand and a sheathing layer, the method comprising the steps of:.

Referring to <FIG>, sheathing repair assembly <NUM> in accordance with some aspects not according to the invention may include an outer tube <NUM> having first end portion <NUM> and second end portion <NUM>, a tubular long seal <NUM>, first and second seals <NUM>, <NUM> positioned in first and second end portions <NUM>, <NUM> of outer tube <NUM>, respectively, and first and second nuts <NUM>, <NUM> each retaining first and second seals <NUM>, <NUM> first and second end portions <NUM>, <NUM> of outer tube <NUM>. Sheathing repair assembly <NUM> may be used to repair a tension member such as tension member <NUM> where sheathing <NUM> is damaged or discontinuous. In one embodiment, sheathing repair assembly <NUM> includes inner tube <NUM>. In another aspect, sheathing repair assembly <NUM> does not include inner tube <NUM>.

The components of the sheathing repair assembly <NUM> may be fully or partially pre-assembled prior to delivery to the pour site or may be assembled at the pour site.

Outer tube <NUM> may be made of an elastomeric polymer. Outer tube <NUM> may be positioned over tension member <NUM> by sliding outer tube <NUM> from an end of tension member <NUM> to a location on tension member <NUM>. In some aspects of the present disclosure, each end portion <NUM>, <NUM> of outer tube <NUM> may include engagement feature <NUM>, such as threads, bayonet tabs or a groove or ridge, to facilitate engagement with first and second nuts <NUM>, <NUM>. In some aspects of the present disclosure, outer tube <NUM> may be provided without engagement feature <NUM>. In some aspects of the present disclosure, the inside diameter of outer tube <NUM> may be greater than the outside diameter of tubular long seal <NUM>. In some aspects of the present disclosure, the inside diameter of outer tube <NUM> may be less than the outside diameter of tubular long seal <NUM>. In some aspects of the present disclosure, the inside diameter of outer tube <NUM> may be substantially the same as the outside diameter of tubular long seal <NUM>.

Tubular long seal <NUM> may be made of elastomeric polymer and may include a compressible elastomer. Tubular long seal <NUM> may be split longitudinally. Tubular long seal <NUM> may be applied from the side of tension member <NUM> by passing the tension member through the slit, so that access to the end of tension member <NUM> is not required. Tubular long seal <NUM> may be sized to receive tension member <NUM> therein. In some aspects of the present disclosure, the inside diameter of tubular long seal <NUM> may be less than the outside diameter of tension member <NUM> so that the inner surface of tubular long seal <NUM> conforms to the outer surface of tension member <NUM>. In some aspects of the present disclosure, the inside diameter of tubular long seal <NUM> may be substantially the same as the outside diameter of tension member <NUM>.

Optional inner tube <NUM> may be made of an elastomeric or non-elastomeric polymer, or a metal. In one embodiment, inner tube <NUM> may have a longitudinal split and may be applied from the side of the tension member. In another embodiment, inner tube <NUM> may have no split and may be positioned on the tension member by sliding inner tube <NUM> from the end of the tension member to a desired position. At least one end portion of inner tube <NUM> may include a hole, tab, or other feature to facilitate movement of inner tube <NUM>. Inner tube <NUM> may be applied to the outside of tubular long seal <NUM> after tubular long seal <NUM> is applied to the tension member <NUM> and before outer tube <NUM> is applied to the outside of tubular long seal <NUM>. Inner tube <NUM> may facilitate the passage of tubular long seal <NUM> into outer tube <NUM>. Inner tube <NUM> may protect tubular long seal <NUM> until outer tube <NUM> is applied to the outside of tubular long seal <NUM>. The inside diameter of inner tube <NUM> may be substantially the same as or less than the outside diameter of tubular long seal <NUM>. The outside diameter of inner tube <NUM> may be substantially the same as the inside diameter of outer tube <NUM>. The outside diameter of inner tube <NUM> may be less than the inside diameter of outer tube <NUM>.

First and second seals <NUM>, <NUM> may be made of elastomeric polymer and may be split longitudinally. First and second seals <NUM>, <NUM> may be applied from the side of tension member <NUM> by passing tension member <NUM> through the slit, so that access to the end of tension member <NUM> is not required.

Each of first and second nuts <NUM>, <NUM> may mechanically engage outer tube <NUM> at engagement feature <NUM>, if present, and may include corresponding internal threads, bayonet tabs or a ridge or groove. In some aspects of the present disclosure, first and second nuts <NUM>, <NUM> may be self-tapping nuts that create threads when threaded onto outer tube <NUM>. In some aspects of the present disclosure, each of first and second nuts <NUM>, <NUM> is a threaded or self-tapping nut engaged with outer tube <NUM>.

When assembled, sheathing repair assembly <NUM> defines a longitudinal passage that is adapted to receive tension member <NUM> and to sealingly engage the outer surface thereof. The presence of sheathing repair assembly <NUM> on tension member <NUM> seals the portion of tension member <NUM> that is within the assembly, i.e. between first and second nuts <NUM>, <NUM>. In each embodiment and each method described herein, repairing a tension member sheath may include re-sheathing to prevent the ingress of fluid into tension member <NUM>.

Referring now to <FIG>, in another embodiment not according to the invention, intermediate anchor and cover assembly <NUM> may include rear nut <NUM>, anchor body <NUM>, encapsulation <NUM>, cap <NUM>, coupler <NUM>, cover <NUM>, and remote nut <NUM>. As illustrated, intermediate anchor and cover assembly <NUM> may be adapted to be received on tension member <NUM>. Tension member <NUM> may include sheathing <NUM>. A portion of sheathing <NUM> may be damaged or absent from the portion of the tension member <NUM> that passes through intermediate anchor and cover assembly <NUM>.

Anchor body <NUM> may be encapsulated in encapsulation <NUM>. Anchor body <NUM> may have an anchor body bore extending therethrough and adapted to receive a tension member such as tension member <NUM>. Anchor body <NUM> may include frustoconical inner surface <NUM> on which plurality of wedges <NUM> may seat when tensioning tension member <NUM> extending through anchor body <NUM>.

Encapsulation <NUM> may have rear surface <NUM> and front surface <NUM>. Rear surface <NUM> may include rear encapsulation extension <NUM> extending outwardly therefrom. Rear encapsulation extension <NUM> may include an inner bore coaxially aligned with the anchor body bore. Rear encapsulation extension <NUM> may be tubular. Rear encapsulation extension <NUM> may or may not be tapered and may or may not include external engagement feature <NUM>, such as threads or bayonet tabs or a groove or ridge for securing a snap-fit. The inside diameter of rear encapsulation extension <NUM> may be greater than the outside diameter of tension member <NUM> or sheathing <NUM> so as to define an annular space therewith.

Rear seal <NUM> may sealingly engage rear encapsulation extension <NUM>. Rear seal <NUM> may be a split seal having a longitudinal split that enables rear seal <NUM> to be applied to a tension member from the side, i.e. without requiring access to the tension member end. Rear seal <NUM> may be made of metal or of a soft elastomer, rubber, silicone, or other suitably deformable sealing material. Rear seal <NUM> may be sized to fit in the annular space between rear encapsulation extension <NUM> and tension member <NUM>. In some aspects of the present disclosure, rear seal <NUM> may have rear seal body <NUM> and rear seal head <NUM>. The outside diameter of rear seal body <NUM> may be the same as or smaller than the inside diameter of rear encapsulation extension <NUM> so that rear seal <NUM> may be applied to the side of tension member <NUM> and then slid along tension member <NUM> and into the annular space between rear encapsulation extension <NUM> and tension member <NUM>.

Rear nut <NUM> may be provided to retain rear seal <NUM>. Rear nut <NUM> may engage rear encapsulation extension <NUM> at external engagement feature <NUM>, if present, and may include corresponding internal threads, bayonet tabs or a ridge or groove. In some aspects of the present disclosure, rear encapsulation extension <NUM> may be provided without an engagement feature and rear nut <NUM> may be a self-tapping nut that creates threads when it is threaded onto rear encapsulation extension <NUM>. Rear seal <NUM> may be sized to have a volume greater than the volume of the annular space between rear encapsulation extension <NUM> and tension member <NUM> so that when rear nut <NUM> is fully engaged on rear encapsulation extension <NUM>, rear seal <NUM> is compressed into a volume that is smaller than it would otherwise occupy. Rear seal head <NUM> may be compressed in an axial direction between rear nut <NUM> and rear encapsulation extension <NUM>. Rear seal <NUM> may be formed of a deformable material that conforms to the shape of the annular space so that when rear nut <NUM> is fully engaged on rear encapsulation extension <NUM> there are no unfilled voids between anchor body <NUM> and rear nut <NUM>.

Front surface <NUM> of encapsulation <NUM> may include front encapsulation extension <NUM> extending outwardly therefrom. Front encapsulation extension <NUM> may be annular and may include an inner bore coaxially aligned with the anchor body bore. Front encapsulation extension <NUM> may or may not include internal threads or bayonet tabs or a groove or ridge for securing a snap-fit.

Cap <NUM> may releasably engage front encapsulation extension <NUM> by, for example, friction fit, threads, or bayonet connection. Cap <NUM> may include engagement interface <NUM>, cap extension <NUM>, and inner bore that may align with the anchor body bore. Engagement interface <NUM> may releasably engage front encapsulation extension <NUM> at the internal threads or bayonet tabs or groove or ridge thereon, if present, and may include corresponding external threads, bayonet tabs or a ridge or groove.

Cap seal <NUM> may be disposed in an annular groove formed in cap <NUM> such that cap seal <NUM> sealingly engages at least one of anchor body <NUM> or encapsulation <NUM> when cap <NUM> is fully engaged on front encapsulation extension <NUM>. Cap seal <NUM> may be annular or toroidal, and may be, for example, an O-ring.

Cap extension <NUM> may be tubular. The inner surface of cap extension <NUM> may be tapered and the outer surface of cap extension <NUM> may include external engagement feature <NUM>, such as threads or bayonet tabs or a groove or ridge for securing a snap-fit. The inside diameter of cap extension <NUM> may be greater than the outside diameter of tension member <NUM> so as to define an annular space therewith.

Front seal <NUM> may sealingly engage cap extension <NUM>. Front seal <NUM> may be a split seal having a longitudinal split that enables front seal <NUM> to be applied to a tension member <NUM> from the side, i.e. without requiring access to the tension member end. Front seal <NUM> may be made of metal or of a soft elastomer, rubber, silicone, or other suitably deformable sealing material. Front seal <NUM> may be sized to fit in the annular space between cap extension <NUM> and tension member <NUM>. Front seal <NUM> may have body <NUM> and head <NUM>. The outside diameter of body <NUM> may be the same as or smaller than the inside diameter of cap extension <NUM> so that front seal <NUM> may be applied to the side of tension member <NUM> and then slid along the tension member and into the annular space between cap extension <NUM> and tension member <NUM>.

Coupler <NUM> may be configured to be rotated about tension member <NUM>. Coupler <NUM> may mechanically couple to cap extension <NUM>. Coupler <NUM> may retain front seal <NUM>. Alternatively or in addition, coupler <NUM> may compress front seal <NUM>. In some aspects of the present disclosure, coupler <NUM> may engage cap extension <NUM> at external engagement feature <NUM>, if present, and may include corresponding internal threads, bayonet tabs or a ridge or groove. In some aspects of the present disclosure, cap extension <NUM> may be provided without an engagement feature and coupler <NUM> may be a self-tapping nut that creates threads as it is threaded onto cap extension <NUM>.

In addition to engaging cap <NUM>, coupler <NUM> may mechanically couple to cover <NUM>. Cover <NUM> may be a split tube, i.e. able to be applied from the side of tension member <NUM>. Cover <NUM> may fit around a tubular long seal <NUM>, which may extend along a portion of the tension member. Cover <NUM> may be longer than tubular long seal <NUM>, so that the ends of cover <NUM> extend beyond the ends of tubular long seal <NUM>, leaving an annular space between each end portion of cover <NUM> and tension member <NUM>. While cover <NUM> may be essentially symmetric, when applied as part of intermediate anchor and cover assembly <NUM>, cover <NUM> will have proximal end portion <NUM> and remote end portion <NUM>.

Proximal end portion <NUM> and remote end portion <NUM> may each include external engagement features <NUM>, <NUM>, respectively, such as threads, bayonet tabs, grooves, or ridges, to facilitate engagement with coupler <NUM> and remote nut <NUM>, respectively. In some aspects of the present disclosure, one or both ends <NUM>, <NUM> of outer tube <NUM> may be provided without an engagement feature and one or both of coupler <NUM> and remote nut <NUM> may include self-tapping threads.

In some aspects, proximal end portion <NUM> of cover <NUM> may include external threads that are reverse threads relative to external threads on cap extension <NUM> so that rotation of coupler <NUM> in one direction about tension member <NUM> will draw cover <NUM> and cap extension <NUM> together and rotation of coupler <NUM> in the other direction about tension member <NUM> will push cover <NUM> and cap extension <NUM> apart.

A proximal seal <NUM> and a remote seal <NUM> may be positioned in the annular spaces between tension member <NUM> and proximal end portion <NUM> and remote end portion <NUM>, respectively. Proximal seal <NUM> may include a head <NUM> and a body <NUM>. Remote seal <NUM> may include head <NUM> and body <NUM>.

In some aspects, proximal seal <NUM> may sealingly engage proximal end portion <NUM> and remote seal <NUM> may sealingly engage remote end portion <NUM>. Proximal seal <NUM> and remote seal <NUM> may each be a split seal having a longitudinal split that enables the seal to be applied to a tension member from the side, i.e. without requiring access to the tension member end. Proximal seal <NUM> and remote seal <NUM> may each be made of metal or of a soft elastomer, rubber, silicone, or other suitably deformable sealing material. The outside diameter of each proximal seal <NUM> and remote seal <NUM> may be the same as or smaller than the inside diameter of cover <NUM> so that each seal may be applied to the side of tension member <NUM> and then slid along the tension member and into the respective annular space between cover <NUM> and tension member <NUM>.

Like rear seal <NUM>, each seal, <NUM>, <NUM>, <NUM> (front, proximate, and remote) may be sized to have a volume greater than the volume of the annular space into which it fits so that assembly of intermediate anchor and cover assembly <NUM> causes each seal to be compressed into a volume that is smaller than it would otherwise occupy. Each seal <NUM>, <NUM>, <NUM> may be formed of a deformable material such that when intermediate anchor and cover assembly <NUM> is fully engaged as described below, there are no substantially unfilled voids between cap <NUM>, coupler <NUM>, proximal end portion <NUM> of cover <NUM> and tension member <NUM> or between remote end portion <NUM> of cover <NUM>, remote nut <NUM>, and tension member <NUM>.

Head <NUM> of front seal <NUM> and head <NUM> of proximal seal <NUM> may both be compressed in an axial direction between the ends of cap extension <NUM> and tubular long seal <NUM>. Head <NUM> of remote seal <NUM> may be compressed in an axial direction between remote nut <NUM> and remote end portion <NUM> of cover <NUM>.

The components of the intermediate anchor and cover assembly <NUM> may be fully or partially pre-assembled prior to delivery to the pour site or may be assembled at the pour site.

In some aspects, rear nut <NUM>, anchor body <NUM> (including encapsulation <NUM>, if present), cap <NUM>, coupler <NUM>, cover <NUM>, and remote nut <NUM> may be applied to tension member <NUM> at an end of the tension member <NUM> and slid along the tension member to the desired location.

Some or all of the components of intermediate anchor and cover assembly <NUM> may be pre-assembled prior to delivery to the pour site or may be assembled at the pour site. For example, components of intermediate anchor and cover assembly <NUM> that are adapted to be mechanically coupled, such as rear nut <NUM> and rear encapsulation extension <NUM>, may be provided in either a coupled or decoupled state. Seals <NUM>, <NUM>, <NUM>, and <NUM> may be but are not necessarily included in the pre-assembly. If included, seals <NUM>, <NUM>, <NUM>, and <NUM> may be removed before initiation of installation steps.

Because intermediate anchor and cover assembly <NUM> may be used at the interface between a first concrete pour and a second, adjacent concrete pour, portions of intermediate anchor and cover assembly <NUM> may be installed before the first pour and portions of intermediate anchor and cover assembly <NUM> may be installed between the first and second pours. Tension member <NUM> extends through both concrete pours. Anchor body <NUM> (including encapsulation <NUM>, if present) may be embedded in the first pour and a front encapsulation extension <NUM> may be shielded by a pocket former (not shown), a removable cap such as cap <NUM>, or the like so as to be exposed between the first and second pours, allowing for connection of cap <NUM> and the remainder of intermediate anchor and cover assembly <NUM>.

In some aspects, rear nut <NUM>, anchor body <NUM> (including encapsulation <NUM>, if present), and cap <NUM> may be positioned, such as at a concrete form that will contain the first pour. Anchor body <NUM> may be affixed to the concrete form with, for example, fasteners that may be placed through holes in encapsulation <NUM>. If coupled to rear encapsulation extension <NUM>, rear nut <NUM> may be decoupled therefrom. Rear seal <NUM> may be applied and slid along tension member <NUM> and into the space between rear encapsulation extension <NUM> and tension member <NUM>. Rear nut <NUM> may then be recoupled to rear encapsulation extension <NUM>, thereby compressing at least a portion of rear seal <NUM> and sealing the rear of the intermediate anchor.

The first concrete pour may then be made. Once the first concrete pour has cured sufficiently, the concrete form may be removed. Cap <NUM> may be decoupled from anchor body <NUM> or encapsulation <NUM> and slid along tension member <NUM> so as to allow access to the anchor body bore. More specifically, access to inner surface <NUM> is provided so that wedges <NUM> may be seated thereon prior to tensioning the tension member <NUM>. Once wedges <NUM> are seated and tension member <NUM> has been tensioned, cap <NUM> may be recoupled to the anchor body <NUM> or encapsulation <NUM>. The portion of tension member <NUM> extending outwardly from anchor body <NUM> through cap <NUM> may or may not be sheathed or, if sheathed, may include a section of damaged sheathing.

Referring now to <FIG>, with cap <NUM> recoupled to the anchor, front seal <NUM> may be slid into the space between cap <NUM> and tension member <NUM>. At another point along tension member <NUM>, proximal seal <NUM> may be slid into the space between cover <NUM> and tension member <NUM>. Cover <NUM>, proximal seal <NUM> and coupler <NUM> may be slid along tension member <NUM> as indicated by the arrow in <FIG> and positioned such that coupler <NUM> is between and adjacent to the end of cap extension <NUM> and the proximal end portion <NUM> of cover <NUM>. The internal engagement mechanism of coupler <NUM> is positioned to engage the external engagement mechanisms of cap <NUM> and cover <NUM>. In some aspects of the present disclosure, because proximal end portion <NUM> is reverse-threaded, rotation of coupler <NUM> may draw cover <NUM> toward cap <NUM>, as indicated by the arrows in <FIG>. Coupler <NUM> may be tightened to a desired torque or until seal heads <NUM>, <NUM> are compressed to a desired degree, as illustrated in <FIG>. Thus, coupler <NUM> may mechanically couple to cap extension <NUM> at a first threaded interface and mechanically couple to proximal end portion <NUM> at a second threaded interface, where the second threaded interface is reversed with respect to the first threaded interface.

Tubular long seal <NUM> may be applied with the afore-mentioned components or may be applied separately from the side of the tension member at a desired location or slid along the tension member to a desired location. In some aspects of the present disclosure, tubular long seal <NUM> may be long enough to fully cover and, optionally, extend beyond an unsheathed portion of tension member <NUM> or, if a portion of sheathing <NUM> has been removed, tubular long seal <NUM> may be positioned between the ends of the sheathing <NUM>. With tubular long seal <NUM> in place between tension member <NUM> and cover <NUM>, remote seal <NUM> may be inserted between tension member <NUM> and remote end portion <NUM> of cover <NUM> and remote nut <NUM> can be tightened into engagement with remote end portion <NUM> to a desired torque or so as to compress remote seal <NUM> to a desired degree.

An inner tube <NUM> may be applied to the outside of tubular long seal <NUM> after tubular long seal <NUM> is applied to the tension member <NUM> and before or after tubular long seal <NUM> is positioned at the unsheathed portion thereof. Inner tube <NUM> may already be present on tension member <NUM> or may be applied from the end of tension member <NUM>.

With rear nut <NUM>, coupler <NUM> and remote nut <NUM> each, intermediate anchor and cover assembly <NUM> may be considered fully assembled. In some aspects of the present disclosure, in the fully assembled state, intermediate anchor and cover assembly <NUM> may include no internal voids. In some aspects of the present disclosure, in the fully assembled state, intermediate anchor and cover assembly <NUM> may provide a fluid-tight seal along the entire portion of tension member <NUM> that is enclosed therein.

When assembled, intermediate anchor and cover assembly <NUM> defines a longitudinal passage that is adapted to receive a tension member and to sealingly engage the outer surface thereof. The presence of the intermediate anchor and cover assembly <NUM> on tension member <NUM> seals the portion of the tension member that is within the assembly, i.e. between each adjacent pair of seals. Thus, portions of tension member <NUM> for which sheathing <NUM> may be damaged or lacking, along with anchor body <NUM> and wedges <NUM>, can be sealed against fluid intrusion. In each embodiment and each method described herein, repairing a tension member may include re-sheathing the portion of the tension member that is within intermediate anchor and cover assembly <NUM> to prevent the ingress of fluid into the tension member <NUM>.

The sheathing repair assembly according to the invention includes two sealing assemblies <NUM>. As shown in <FIG>, sealing assembly <NUM> is shown in combination with a tension member <NUM>. Part of tension member <NUM> is enclosed in sheathing <NUM>. Sealing assembly <NUM> includes male nut <NUM>, female nut <NUM>, and forcing element <NUM>, and is provided in conjunction with repair tube <NUM>. In some aspects, sealing assembly <NUM> may also include proximal seal <NUM> as described above.

Male nut <NUM> has first end portion <NUM>, second end portion <NUM> and central bore <NUM> therethrough. The outer surface of first end portion <NUM> includes at least one male thread <NUM>. As shown in <FIG>, the outside surface of male nut <NUM> may include one or more radial tabs <NUM> to facilitate rotation of male nut <NUM>.

Female nut <NUM> has first end portion <NUM> and second end portion <NUM>. The inner surface of first end portion <NUM> includes at least one female thread <NUM>. Female thread <NUM> corresponds to and is adapted to engage male thread <NUM> so as to mechanically couple female nut <NUM> to male nut <NUM>. In some aspects, threads <NUM>, <NUM> may be configured so as to couple nuts <NUM>, <NUM> with one relative rotation or less. In some aspects, threads <NUM>, <NUM> may be replaced with, for example and without limitation, a bayonet connector, plastically deformable tabs, or a friction fit.

The inner surface of second end portion <NUM> includes a frustoconical inner surface that defines a forcing cone <NUM>. The diameter of forcing cone <NUM> diminishes in the direction away from first end portion <NUM>. Referring briefly to <FIG>, the outside of female nut <NUM> may include one or more radial tabs <NUM> to facilitate rotation.

Forcing element <NUM> is adapted to serve as an expansion element, whereby insertion of forcing element <NUM> to an end of repair tube <NUM> causes radial expansion thereof. Forcing element <NUM> may be a barbed ferrule and has a frustoconical outer surface <NUM> and central bore <NUM> corresponding to central bore <NUM> of male nut <NUM>. Outer surface <NUM> may be smooth or may include a friction device <NUM> on its outer surface <NUM>. Friction device <NUM> may include, for example and without limitation, barbs, grooves or a roughened surface. In some aspects, outer surface <NUM> of forcing element <NUM> may also include an optional circumferential groove <NUM>. Groove <NUM> may be closer to the large end of forcing element <NUM> and may be adapted to receive seal <NUM>. Seal <NUM> may be an O-ring. Seal <NUM> may be made of polymer or metal or any suitable material.

In some aspects washer <NUM> may be positioned between forcing element <NUM> and first end portion <NUM> of male nut <NUM>. In some aspects, a portion of forcing element <NUM> is between washer <NUM> and seal <NUM>; in other aspects, forcing element <NUM> is configured such that washer <NUM> is adjacent to seal <NUM>. Washer <NUM>, if present, facilitates rotation, including rotation of male nut <NUM> relative to forcing element <NUM>. In some aspects, female nut <NUM>, forcing element <NUM>, washer <NUM>, and seal <NUM> may be provided as a preassembled unit, or cartridge. Washer <NUM> may be made of polymer or metal or any suitable material.

According to the invention, both ends of repair tube <NUM> include an expansion portion <NUM>. Expansion portion <NUM> may optionally include one or more of the following features: a tapered wall thickness, longitudinal slots or grooves, and one or more internal or external friction devices. Before insertion of forcing element <NUM>, the diameter of expansion portion <NUM> is the same as or greater than the diameter of the rest of repair tube <NUM>.

Repair tube <NUM> may include sealing assembly <NUM> at each end <NUM>. In such instances, repair tube <NUM> may include expansion portion <NUM> at each end <NUM>. A repair assembly includes repair tube <NUM>, and two sealing assemblies <NUM> that each include male nut <NUM>, female nut <NUM>, and forcing element <NUM>.

According to some aspects, when it is desired to enclose a defect in a sheathing layer on a tension member <NUM>, a repair assembly may be positioned at the desired location along tension member <NUM>. For example, a repair assembly may be positioned such that the two sealing assemblies <NUM> are positioned on tension member <NUM> with the defect between the two sealing assemblies <NUM> and the repair tube <NUM> spanning the defect. Each sealing assembly <NUM> may be actuated by inserting the narrow end of forcing element <NUM> into an end of repair tube <NUM>. In certain aspects, where female nut <NUM>, forcing element <NUM>, washer <NUM>, and seal <NUM> are provided as a preassembled unit, the pre-assembled unit may be slid along the outside of tension member <NUM> and into engagement with repair tube <NUM>. Insertion of forcing element <NUM> into end of repair tube <NUM> may expand the end of repair tube <NUM> radially outward. Male nut <NUM> may then be coupled to female nut <NUM> by engaging threads <NUM>, <NUM>. Sealing assembly <NUM> may be configured such that when threads <NUM>, <NUM> are fully engaged, the end of repair tube <NUM> is compressed between forcing cone <NUM> and the outer surface <NUM> of forcing element <NUM>. If a seal <NUM> is present, engagement of threads <NUM>, <NUM> may also compress seal <NUM>.

According to the invention, the sheathing repair assembly includes two sealing assemblies <NUM>. <FIG> depicts sealing assembly <NUM>, which is adapted for use with an anchor such as an intermediate post-tensioning concrete anchor. Sealing assembly <NUM> includes female nut <NUM>, repair tube <NUM>, and cap <NUM>. Cap <NUM> may have anchor-engaging end <NUM> including engagement interface <NUM>, outwardly extending cap extension <NUM>, and sealing end <NUM>. As described above with respect to <FIG>, an intermediate post-tensioning concrete anchor may include anchor body <NUM> having encapsulation <NUM> and front encapsulation extension <NUM>. As described above with respect to <FIG>, both ends <NUM> of repair tube <NUM> include an expansion portion <NUM>.

Anchor-engaging end <NUM> of cap <NUM> may releasably engage front encapsulation extension <NUM> by any suitable means including but not limited to friction fit, threads, or bayonet connection. Engagement interface <NUM> may releasably engage front encapsulation extension <NUM> at the internal threads or bayonet tabs or groove or ridge thereon, if present, and may include corresponding external threads, bayonet tabs or a ridge or groove. A cap seal <NUM> may be disposed in an annular groove formed in cap <NUM> such that cap seal <NUM> sealingly engages at least one of anchor body <NUM> or encapsulation <NUM> when cap <NUM> is coupled to front encapsulation extension <NUM>. Cap seal <NUM> may be annular or toroidal, and may be, for example, an O-ring.

Cap extension <NUM> may be generally tubular and serves as a forcing element. The inner surface of cap extension <NUM> may include a central bore <NUM>. The portion of cap extension <NUM> adjacent to sealing end <NUM> includes a wedging portion <NUM> having a frustoconical outer surface <NUM>. Frustoconical outer surface <NUM> may include a friction device, which may include, for example, barbs, grooves or a roughened surface. Frustoconical outer surface <NUM> is configured such that frustoconical outer surface <NUM> can be inserted into an end of repair tube <NUM> so as to cause a partial radial expansion thereof.

The outer surface of cap extension <NUM> may also include an external engagement feature <NUM> between wedging portion <NUM> and anchor-engaging end <NUM>. In the illustrated embodiment, engagement feature <NUM> includes threads, but in other aspects engagement feature <NUM> may include, for example, a bayonet coupling or a groove or ridge for securing a snap-fit.

Female nut <NUM> may include at least one female thread <NUM>. Female thread <NUM> may correspond to and be adapted to engage engagement feature <NUM>, such as a male thread so as to mechanically couple female nut <NUM> to cap <NUM>. In some aspects, threads <NUM>, <NUM> may be configured so as to couple female nut <NUM> to cap <NUM> with one relative rotation or less. In some aspects, threads <NUM>, <NUM> may be replaced with, for example, a bayonet connector, plastically deformable tabs, or a friction fit.

Female nut <NUM> may also include a frustoconical inner surface that defines forcing cone <NUM>. Forcing cone <NUM> is configured to cooperate with frustoconical outer surface <NUM> of cap <NUM> so as to compress an end of repair tube <NUM> when female nut <NUM> is coupled to cap <NUM>. In some aspects, the outside of female nut <NUM> may include one or more radial tabs to facilitate rotation of female nut <NUM>.

Second female nut <NUM> may be adapted to mechanically couple to rear encapsulation extension <NUM> of an anchor. Female nut <NUM> may be provided with an internal coupling feature <NUM> and rear encapsulation extension <NUM> may be provided with a corresponding external coupling feature <NUM>. In the illustrated embodiment, coupling features <NUM>, <NUM> are shown as threads, but coupling features <NUM>, <NUM> could be, for example, a bayonet coupling or a groove or ridge for securing a snap-fit. In some aspects, coupling features <NUM>, <NUM> may be configured so as to couple second female nut <NUM> to rear encapsulation extension <NUM> with one relative rotation or less. In some aspects of the present disclosure, a longitudinally split seal that enables the seal to be applied to a tension member from the side in the manner described above with respect to proximal seal <NUM> and remote seal <NUM> may be included between female nut <NUM> and rear encapsulation extension <NUM>.

In certain aspects not according to the invention, a sheathing repair assembly may include two sealing devices <NUM>. <FIG> depicts sealing devices <NUM> that includes female nut <NUM>, forcing element <NUM>, and repair tube <NUM>. Female nut <NUM> may be a self-tapping nut that is adapted to create a sealed, threaded coupling with the outside of repair tube <NUM>. Forcing element <NUM> may be a split seal and may be adapted to serve as a forcing element. Forcing element <NUM> may have a tapered outer surface that cooperates with an inner surface of female nut <NUM> to compress an end of repair tube <NUM> therebetween when female nut <NUM> is coupled to repair tube <NUM>.

<FIG> depicts sealing device <NUM> not according to the invention that includes female nut <NUM>, split seal <NUM>, tubular long seal <NUM>, optional inner tube <NUM>, and repair tube <NUM>. Female nut <NUM> may be a self-tapping nut that is adapted to create a sealed, threaded coupling with the outside of repair tube <NUM>. Split seal <NUM> may be adapted to serve as a forcing element. Split seal <NUM> may have a tapered outer surface that cooperates with an inner surface of female nut <NUM> to compress an end of repair tube <NUM> therebetween when female nut <NUM> is coupled to repair tube <NUM>. Long seal <NUM> and inner tube <NUM> may be as described above with respect to long seal <NUM> and inner tube <NUM>.

<FIG> depicts sealing assembly <NUM> consistent with certain aspects that is adapted for use with an anchor, such as intermediate post tensioning anchor <NUM>. Sealing assembly <NUM> includes first sealing device <NUM> and second sealing device <NUM>. First sealing device includes female nut <NUM>, male nut <NUM>, split seal <NUM>, mandrel/pocket former <NUM>, gasket <NUM>, and repair tube <NUM>.

Split seal <NUM> may include a longitudinal split that enables split seal <NUM> to be applied to a tension member <NUM> from the side, i.e. without requiring access to the tension member end. Split seal <NUM> may be made of metal or of a soft elastomer, rubber, silicone, or other suitably deformable sealing material. Split seal <NUM> may be sized to fit in the annular space between female nut <NUM> and tension member <NUM>.

Intermediate post tensioning anchor <NUM> may include anchor body <NUM> covered by encapsulation <NUM>, having encapsulation extension <NUM>. The combination of split seal <NUM>, female nut <NUM>, and encapsulation extension may form a seal. Back end <NUM> of anchor body <NUM> is adapted to receive gasket <NUM> and mandrel/pocket former <NUM>.

Second sealing device <NUM> is formed as described above with respect to <FIG> and <FIG>, having male nut <NUM>, forcing element <NUM>, and two split seals <NUM>, <NUM> positioned on either side of forcing element <NUM>. Female nut <NUM> fits with male nut <NUM>, as described with respect to <FIG>.

When assembled, sealing assemblies <NUM>, <NUM>, <NUM>, and sealing devices <NUM>, <NUM> each define a longitudinal passage that is adapted to receive a tension member and sealingly engage the outer surface thereof. The presence of a sealing assembly <NUM>, <NUM> or sealing device <NUM>, <NUM> on tension member <NUM> seals the portion of the tension member that is within the assembly, e.g., between male nut <NUM> and female nut <NUM>. In each embodiment and each method described herein, repair of a sheathing layer may be for the purpose of re-sealing a sheath that has become damaged or replacement of a sheathing layer on a portion of strand from which the sheathing has been removed.

In some aspects not according to the invention, an assembly for use with a tension member for post-tensioning concrete may include an anchor body, an encapsulation, wherein the encapsulation at least partially encapsulates the anchor body and wherein the encapsulation includes a rear encapsulation extension and a front encapsulation extension, a rear nut mechanically coupled to the rear encapsulation extension, a cap mechanically coupled to the front encapsulation extension, the cap including a cap extension, a cover extending around a portion of the tension member, the cover being tubular and having a proximal end portion and a remote end portion, a coupler mechanically coupled to both the cap extension and the proximal end portion, and a remote nut mechanically coupled to the remote end portion.

The assembly may further include a rear seal positioned between the rear encapsulation extension and the tension member, a front seal positioned between the cap extension and the tension member, a proximal seal positioned between the proximal end portion and the tension member, and a remote seal positioned between the remote end portion and the tension member. The rear, front, proximal, and remote seals may each be a split seal. The rear, front, proximal, and remote seals may each be sized such that tightening the rear nut, coupler and remote nut to a desired degree deforms the rear, front, proximal, and remote seals such that there are substantially no internal voids in the assembly.

In some aspects, the assembly may further include a rear seal positioned between the rear extension and the tension member and the rear seal may include a head compressed in an axial direction between the rear nut and rear encapsulation extension.

In some aspects, the assembly may further include a front seal positioned between the cap extension and the tension member, a proximal seal positioned between the proximal end portion and the tension member, and a long seal positioned between the tension member and the cover and the front seal and the proximal seal may each include a head compressed in an axial direction between the cap extension and the long seal.

In some aspects, the assembly may further include a remote seal positioned between the remote end portion and the tension member and the rear seal may include a head compressed in an axial direction between the remote nut and the remote end portion of the cover.

In some aspects, the coupler may mechanically couple to the cap extension at a first threaded interface and may mechanically couple to the proximal end portion at a second threaded interface. The second threaded interface may be reversed with respect to the first threaded interface.

The assembly may further include a cap seal disposed in an annular groove formed in the cap, wherein the cap seal engages at least one of the anchor body or the encapsulation.

In some aspects not according to the invention, a method for providing an intermediate anchor and cover on a tension member for post-tensioning concrete, may include the steps of a) positioning components of an intermediate anchor and cover assembly on the tension member at desired locations, the components comprising: an anchor body, an encapsulation, wherein the encapsulation at least partially encapsulates the anchor body and wherein the encapsulation includes a rear encapsulation extension and a front encapsulation extension, a rear nut, a cap, wherein the cap includes a cap extension, a cover, wherein the cover is tubular and has a proximal end portion and a remote end portion, a coupler; and a remote nut; b) mechanically coupling the cap to the front encapsulation extension; c) positioning a rear seal between the rear encapsulation extension and the tension member and mechanically coupling the rear nut to the rear encapsulation extension; d) positioning a front seal between the cap extension and the tension member; e) positioning a long seal at a desired location on the tension member; f) positioning the cover around the tubular long seal; g) positioning a proximal seal between the proximal end portion and the tension member; h) mechanically coupling the coupler to the cap extension and the proximal end portion; and i) positioning a remote seal between the remote end portion and the tension member and mechanically coupling the remote nut to the remote end portion.

In some aspects not according to the invention, a kit for assembling an intermediate anchor and cover assembly for use with a tension member for post-tensioning concrete may include: an anchor body; an encapsulation, the encapsulation at least partially encapsulating the anchor body and including a rear encapsulation extension and a front encapsulation extension; a rear nut adapted to mechanically couple to the rear encapsulation extension; a cap adapted to mechanically couple to the front encapsulation extension, the cap including a cap extension; a cover adapted to extend around a portion of the tension member, the cover being tubular and having a proximal end portion and a remote end portion; a coupler adapted to mechanically couple to both the cap extension and the proximal end portion; and a rear nut adapted to mechanically couple to the remote end portion.

In various aspects, the sheathing repair assembly may include an inner tube positioned between the outer tube and the tubular long seal. The first elastomeric seal may be configured such that mechanically coupling the first nut to the outer tube causes the first elastomeric seal to fill an annular space defined between the outer tube, the long seal, the tension member, and the first nut, and the second elastomeric seal may be configured such that mechanically coupling the second nut to the outer tube causes the second elastomeric seal to fill an annular space defined between the outer tube, the long seal, the tension member, and the second nut.

The outer tube may not have a longitudinal slit. The first and second elastomeric seals may each have a longitudinal slit. The long seal may have a longitudinal slit.

The tension member may have an unsealed portion and the long seal may be long enough to fully cover the unsealed portion. The long seal may be long enough to extend beyond the unsealed portion.

A method for repairing an unsheathed portion of a sheathed tension member not according to the invention may include the steps of: a) providing a sheathing repair assembly comprising an outer tube having first and second end portions, a tubular long seal sized to fit onto the tension member, a first elastomeric seal sized to fit onto the tension member, a second elastomeric seal sized to fit onto the tension member, a first nut adapted to mechanically couple to one end portion, and a second nut adapted to mechanically couple to one end portion, b) positioning the tubular long seal at the unsheathed portion, c) positioning the outer tube around the tubular long seal, d) inserting the first elastomeric seal into the first end portion and coupling the first nut to the first end portion so as to retain the first elastomeric seal therein, e) inserting the second elastomeric seal into the second end portion and coupling the second nut to the second end portion so as to retain the second elastomeric seal therein. The method may further include the step of positioning an inner tube between the tubular long seal and the outer tube before step d). The method may further include the step of removing the inner tube from between the tubular long seal and the outer tube before step d).

Claim 1:
A sheathing repair assembly (<NUM>) for a tension member of a post-tensioning tendon, the tension member (<NUM>) comprising a strand and a sheathing layer, the sheathing repair assembly (<NUM>) comprising:
a repair tube (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having first (<NUM>) and second end (<NUM>) portions;
a first sealing assembly (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising:
a first nut (<NUM>) having a first frustoconical surface (<NUM>, <NUM>); and
a first forcing element (<NUM>) adapted to cooperate with the first frustoconical surface (<NUM>) so as to compress the first end portion (<NUM>, <NUM>, <NUM>) of the repair tube (<NUM>, <NUM>, <NUM>, <NUM>); and
a second sealing assembly comprising:
a second nut (<NUM>) having a second frustoconical surface (<NUM>, <NUM>); and
a second forcing element (<NUM>) adapted to cooperate with the second frustoconical surface (<NUM>, <NUM>) so as to compress the second end portion (<NUM>, <NUM>, <NUM>) of the repair tube (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
wherein the first and second end portions (<NUM>, <NUM>, <NUM>, <NUM>) of the repair tube (<NUM>, <NUM>, <NUM>, <NUM>) each includes an expansion portion (<NUM>, <NUM>) that includes:
a tapered wall thickness,
a diameter greater than a diameter of the rest of the repair tube (<NUM>, <NUM>, <NUM>, <NUM>),
longitudinal slots, longitudinal grooves, an internal friction device, or an external friction device, characterized by:
the first end portion (<NUM>, <NUM>, <NUM>) of the repair tube (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) being compressed between the first forcing element (<NUM>, <NUM>) and the first frustoconical surface, and;
the second end portion (<NUM>, <NUM>, <NUM>) of the repair tube (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) being compressed between the second forcing element and the second frustoconical surface.