US20100322717A1

US20100322717A1 - Pile Splice Assemblies, Pile Systems Involving Such Assemblies and Methods for Splicing Piles

Info

Publication number: US20100322717A1
Application number: US12/487,708
Authority: US
Inventors: Larry A. Paul
Original assignee: Standard Concrete Products Inc
Current assignee: Standard Concrete Products Inc
Priority date: 2009-06-19
Filing date: 2009-06-19
Publication date: 2010-12-23

Abstract

Pile splice assemblies, pile systems involving such assemblies and methods for splicing piles are provided. In this regard, a representative method includes: using strand locking devices to attach first and second anchors to respective strands of first and second piles; and securing the first and second anchors to each other.

Description

BACKGROUND

1. Technical Field
The disclosure generally relates to prestressed concrete piles.
2. Description of the Related Art
Prestressed concrete piles use strands to exert compressive loads to surrounding concrete of the piles. The strands run the lengths of the piles and can be provided in various forms, such as bars and cables. The compressive loads provided by the strands tend to offset tensile forces to which the piles can be exposed.

SUMMARY

Pile splice assemblies, pile systems involving such assemblies and methods for splicing piles are provided. In this regard, an exemplary embodiment of a method for splicing prestressed concrete piles comprises: using strand locking devices to attach first and second anchors to respective strands of first and second piles; and securing the first and second anchors to each other.
An exemplary embodiment of a pile splice assembly for use with prestressed concrete piles, the piles having strands extending the lengths of the piles, comprises: first and second pile anchors, each of said anchors having a plurality of anchor holes and a plurality of splice holes formed therethrough, each of said anchor holes being positioned to align with a corresponding one of the strands; strand locking devices operative to attach said first pile anchor to the first pile and to attach said second pile anchor to the second pile, each of said strand locking devices having wedges, each of said anchor holes being sized and shaped to receive a corresponding one of said strand locking devices such that corresponding ones of said wedges engage corresponding ones of the strands; and fasteners, each of said fasteners being sized and shaped to mount through a corresponding pair of said splice holes such that said first and second pile anchors are secured to each other in an overlying relationship via said fasteners with the prestressed concrete piles extending outwardly along a common axis from said first and second pile anchors.
An exemplary embodiment of a pile system comprises: first and second prestressed concrete piles, each of the piles having strands extending respective lengths thereof; a pile splice assembly having first and second pile anchors and chucks; each of the anchors having a plurality of anchor holes formed therethrough, each of the anchor holes being positioned to align with a corresponding one of the strands; the chucks being operative to attach the first pile anchor to the first pile and to attach the second pile anchor to the second pile, each of the chucks having a chuck body and chuck jaws, each of the anchor holes being sized and shaped to receive a corresponding one of the chucks such that corresponding chuck jaws engage corresponding ones of the strands; the first and second anchors being operative to secure together such that the prestressed concrete piles are spliced together in an end-to-end relationship.
Other systems, methods, features and/or advantages of this disclosure will be or may become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features and/or advantages be included within this description and be within the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.

FIG. 1 is a partially-exploded, perspective view of a portion of an embodiment of a pile system.

FIG. 2 is a plan view of an embodiment of a pile anchor showing representative fastener and chuck placement.

FIG. 3 is a plan view of the end of an embodiment of a pile.

FIG. 4 is a partially cut-away view of the embodiment of FIG. 1, as viewed along section line 4-4.

FIG. 5 is a cut-away view of the embodiment of FIG. 1, as viewed along section line 5-5.

FIG. 6 is a cut-away view of an embodiment of pile system, showing detail of strand chuck setting device installing chuck jaws to secure an anchor to an end of a pile.

FIG. 7 is a cut-away view of the embodiment of FIG. 6, showing representative chucks in greater detail.

FIG. 8 is a schematic diagram depicting ends of piles oriented for attachment.

FIG. 9 is a schematic diagram depicting the piles of FIG. 8 after attachment.

FIG. 10 is a cut-away view of the piles of FIG. 9, showing detail of the chucks.

FIG. 11 is a schematic diagram depicting ends of piles oriented for attachment using an alternative fastener configuration.

FIG. 12 is a partially-exploded, schematic view of a portion of another embodiment of a pile system.

FIG. 13 is a partially-exploded, schematic view of a portion of another embodiment of a pile system.

DETAILED DESCRIPTION

Pile splice assemblies, pile systems involving such assemblies and methods for splicing piles are provided, several exemplary embodiments of which will be described in detail. In this regard, strand locking devices are used to attach anchors to the ends of prestressed concrete piles. As used herein, the term strand locking device is used to describe a family of mechanical components that incorporate wedges and inclined surfaces that interact with the wedges for engaging about a strand such that attempts to pull a strand from a strand locking device typically causes the wedges to grip more tightly about the strand. In some embodiments, strand chuck-type strand locking devices (e.g., detachable strand chucks) are used. Notably, the piles include strands that extend along the lengths of the piles, with the strands being configured to compressively load the surrounding concrete of the piles. The strand locking devices engage the strands to secure the anchors to adjacent ends of two piles that are to be spliced. The anchors are then secured to each other, such as by using mechanical fasteners, resulting in a spliced pile that exhibits moment capacity (i.e., the moment capacity approaching that of a pile of similar length without the splice).
FIG. 1 is a partially-exploded, perspective view of a portion of an embodiment of a pile system. As shown in FIG. 1, pile system 100 includes two prestressed concrete piles 102, 104 (only portions of which are shown). Notably, the piles incorporate strands; for example, pile 102 incorporates a strand 106, and pile 104 incorporates a strand 108. The strands extend along the lengths of the piles, with ends of the strands typically protruding from the corresponding concrete ends of the piles.
System 100 also includes a pile splice assembly 110. In this embodiment, assembly 110 incorporates pile anchors 112, 114, strand locking devices (e.g., chuck 116), and a setting device 117. Anchor holes (e.g., anchor hole 118) and splice holes (e.g., splice hole 120) are formed through the anchors. Specifically, each of the anchor holes is positioned to align with a corresponding one of the strands. By way of example, anchor hole 118 is aligned with strand 106, and anchor hole 122 is aligned with strand 108. In contrast, each of the splice holes of anchor 102 is oriented to align with a corresponding splice hole of anchor 104 so that each pair of splice holes can receive a fastener (e.g., a bolt 126). For instance, splice hole 120 is aligned with splice hole 128.
The anchors are attached to the piles by the strand chucks that are positioned in this embodiment by a setting device. For instance, anchor 114 is attached to end 129 of pile 104. As will be described in greater detail, each of the chucks includes a chuck body (that is received by a corresponding anchor hole) and chuck jaws or wedges (that are positioned within the chuck body and about a corresponding strand). Notably, the chuck jaws are designed to resist a pulling movement of the strand away from the chuck as such movement tends to force the chuck jaws closer together (i.e., grip more tightly about the strand). After being fastened to the piles by the chucks, the anchors are secured together so that the piles are spliced in an end-to-end relationship.
FIG. 2 is a plan view of an embodiment of a pile anchor showing representative fastener and chuck placement. As shown in FIG. 2, anchor 114 is formed of a substantially rectangular plate of metal (e.g., steel) that exhibits relatively uniform thickness. Typically, the cross-section of the anchor is shaped to correspond to the cross-section of the pile to which it is to be attached. However, various other shapes and configurations can be used in other embodiments.
Anchor holes (e.g., anchor hole 122) that are used to mount the strand chucks are uniformly spaced about the anchor. In this embodiment, the chucks (e.g., chuck 142) are positioned to form a rectangular arrangement of the chucks. The anchor holes (and, therefore, the chucks) are positioned radially inboard of the splice holes (e.g., splice hole 128) and corresponding fasteners (e.g., bolt 126). Specifically, in this embodiment, the splice holes are positioned adjacent to the corners of the anchor, with each corner mounting a corresponding pair of fasteners. Various other numbers and/or arrangements of anchor and splice holes can be used in other embodiments.
FIG. 3 is a plan view of the end of an embodiment of a pile. In particular, end 129 of pile 104 is depicted. Notably, end 129 includes a distal surface 146 and fastener pockets located at each of the corners of the pile. For instance, pocket 148 is located at corner 150. In this embodiment, each of the pockets is formed as a recessed portion of the end of the pile so that, when the end is engaged by an anchor, each recess forms a pocket between the outer surface of the pile end and the underside of the anchor. The fastener pockets are configured to facilitate placement of the fasteners.
FIG. 4 is a partially cut-away view of the embodiment of FIG. 1, as viewed along section line 4-4, showing a portion of an embodiment of a setting device in greater detail. Additionally, FIG. 5 is a cut-away view of the embodiment of FIG. 1, as viewed along section line 5-5. With reference to FIGS. 4 and 5 (and with brief reference to FIG. 1), setting device 117 includes setting components 152, 154. In this embodiment, each of the setting components is generally planar (e.g., formed of steel plate), with protrusions (e.g., protrusions 156, 158) extending outwardly from the outward-facing surfaces for setting the wedges of corresponding strand locking devices. In this embodiment, the protrusions are located about the peripheries of the setting components.
The setting components are movable between a retracted position, in which the components are close to each other, and an extended position, in which the components are spaced farther apart. Movement from the retracted to the extended position facilitates simultaneous positioning of, in this case, the jaws of strand chucks for securing both anchors to piles that are to be spliced.
In the embodiment of FIGS. 1, 4 and 5, movement of the setting components between the retracted and extended positions is performed by a hydraulic ram set 160, although various other types of actuation can be used in other embodiments. Ram set 160 includes four actuators (e.g., actuator 162) that receive hydraulic fluid via lines 164. Note that an associated reservoir and pump are not depicted.
The setting components are suspended between piles by a hanger 170 that spans the gap between the ends of the piles. The setting components hang downwardly from the hanger and move linearly along tracks (e.g., track 172) provided on an underside 174 of the hanger. Note that, in FIG. 5, temporary spacers (e.g., spacer 180) are used to prevent damage to the pile ends and setting device during positioning. After setting of the strand chucks, the spacers are typically removed to facilitate attachment of the anchors to each other.
FIGS. 6 and 7 are cut-away views of an embodiment of a pile system, showing detail of a setting device installing chuck jaws to secure an anchor to the end of a pile. Notably, the setting device is moving as indicated by arrows A to an extended position. As shown, each of the anchor holes of the depicted anchor 190 is defined by an aperture that includes internal threads for engaging external threads of a corresponding strand chuck (e.g., chuck 191). For example, threads 192 of anchor hole 194 engage threads 196 of chuck body 198. The chuck jaws (e.g., jaws 200) are positioned within a cavity (e.g., cavity 202) of a chuck body and are positioned about a strand (e.g., strand 206).
Setting component 210 of a setting device includes annular protrusions (e.g., protrusion 212), each of which surrounds a corresponding bore (e.g., bore 214). Each bore is sized to receive a strand therethrough so that each protrusion can engage the jaws of a corresponding strand chuck and urge the jaws into engagement about a strand. In so doing, each protrusion extends at least partially into the cavity of a corresponding chuck body to seat the jaws.
FIG. 8 is a schematic diagram depicting ends of piles 216, 218 oriented for splicing. Note that temporary guide pins (e.g., guide pins 220, 222) are used to align anchors 224, 226 relative to each other. Each of the guide pins incorporates a tapered end, which facilitates alignment of corresponding splice holes by being positioned in the splice holes of one of the anchors and enabling a corresponding splice hole to be seated about the guide pin. In FIG. 8, for example, splice hole 228 carries guide pin 220, which is used to align splice hole 230 of anchor 226.
After alignment, the guide pins are removed and fasteners (e.g., bolt and nut assembly 237) can be inserted through the aligned splice holes (FIG. 9), which can include accessing the splice holes via the fastener pockets (e.g., pocket 238). Note that after splicing, piles 216, 218 extend outwardly from the anchors along a common axis 240. Note also that FIG. 10 is a cut-away view of the piles of FIG. 9, showing detail of the strand chucks that are used to secure the anchors to the piles.
FIG. 11 is a schematic diagram depicting ends of piles oriented for attachment using an alternative fastener configuration. In contrast to the configuration depicted in FIG. 9, in which the bolt heads of the fasteners are positioned within the fastener pockets, the nuts of the fasteners are so positioned. For instance, nut 252 is positioned within pocket 254, while corresponding bolt head 256 is positioned beneath anchor 258 on the opposing pile.
FIG. 12 is a schematic view of a portion of another embodiment of a pile system that includes an anchor 280. In contrast to embodiments of pile systems that incorporate separate strand locking devices, this embodiment exhibits an integrated configuration. Specifically, anchor 280 includes an anchor hole 282 that is defined by a tapered sidewall 284. Sidewall 284 and wedges (in this case, two wedges 286, 287) form a strand locking device for engaging a strand (not shown). In some embodiments, the thickness of the anchor, particularly at locations that receive wedges, may be thicker than a comparable anchor that receives a separate strand locking device. Notably, various numbers and configurations of wedges can be used.
FIG. 13 is schematic view of a portion of another embodiment of a pile system. In contrast to embodiments of pile systems that incorporate externally-threaded chuck bodies that engage threaded apertures of an anchor, this embodiment uses an alternative configuration to mount the chuck bodies. Specifically, anchor 290 includes an anchor hole 292 that is defined by a bore 293 and an annular recess 294. The recess is sized and shaped to receive the flange 295 of a chuck body 296. The flange is designed to prevent the chuck body from being pulled through the anchor hole. In other embodiments, various other configurations can be used to mount a strand locking device to an anchor. Wedges 297, 298 also are depicted in FIG. 13.
It should be emphasized that the above-described embodiments are merely possible examples of implementations set forth for a clear understanding of the principles of this disclosure. Many variations and modifications may be made to the above-described embodiments without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the accompanying claims.

Claims

1. A pile splice assembly for use with prestressed concrete piles, the piles having strands extending the lengths of the piles, said pile splice assembly comprising:

first and second pile anchors, each of said anchors having a plurality of anchor holes and a plurality of splice holes formed therethrough, each of said anchor holes being positioned to align with a corresponding one of the strands;

strand locking devices operative to attach said first pile anchor to the first pile and to attach said second pile anchor to the second pile, each of said strand locking devices having wedges, each of said anchor holes being sized and shaped to receive a corresponding one of said strand locking devices such that corresponding ones of said wedges engage corresponding ones of the strands; and

fasteners, each of said fasteners being sized and shaped to mount through a corresponding pair of said splice holes such that said first and second pile anchors are secured to each other in an overlying relationship via said fasteners with the prestressed concrete piles extending outwardly along a common axis from said first and second pile anchors.

2. The assembly of claim 1, wherein at least one of said strand locking devices is a chuck having a chuck body and chuck jaws.

3. The assembly of claim 2, wherein:

said chuck body has external threads; and

a corresponding one of said anchor holes is defined by a corresponding internally-threaded aperture sized and shaped to engage the external threads of said chuck body.

4. The assembly of claim 1, wherein said chuck body is integrally formed with said first anchor.

5. The assembly of claim 1, wherein the first anchor is a substantially planar plate formed of metal.

6. The assembly of claim 1, wherein each of said fasteners comprises a bolt and nut.

7. The assembly of claim 1, wherein:

said splice holes are positioned adjacent corners of said anchors; and

said fasteners comprise pairs of fasteners such that each of said corners mounts a corresponding one of said pairs of fasteners.

8. The assembly of claim 1, wherein said anchor holes are uniformly spaced about said anchors.

9. The assembly of claim 1, further comprising guide pins operative to align said first and second anchors relative to each other.

10. A pile system comprising:

first and second prestressed concrete piles, each of the piles having strands extending respective lengths thereof;

a pile splice assembly having first and second pile anchors and chucks;

each of the anchors having a plurality of anchor holes formed therethrough, each of the anchor holes being positioned to align with a corresponding one of the strands;

the chucks being operative to attach the first pile anchor to the first pile and to attach the second pile anchor to the second pile, each of the chucks having a chuck body and chuck jaws, each of the anchor holes being sized and shaped to receive a corresponding one of the chucks such that corresponding chuck jaws engage corresponding ones of the strands;

the first and second anchors being operative to secure together such that the prestressed concrete piles are spliced together in an end-to-end relationship.

11. The system of claim 10, wherein:

each of the anchors has a plurality of splice holes formed therethrough; and

the system further comprises fasteners, each of the fasteners being sized and shaped to mount through a corresponding pair of the splice holes such that the first and second pile anchors are securable to each other in an overlying relationship via the fasteners.

12. The system of claim 10, wherein the prestressed concrete piles extend outwardly along a common axis from the first and second pile anchors.

13. The system of claim 10, wherein the first prestressed concrete pile has fastener pockets located at a first end thereof, the fastener pockets being configured as recessed portions of the first end such that each of the fastener pockets forms a corresponding void between the first anchor and the first end, each of the fastener pockets being sized and shaped to facilitate attachment of a mechanical fastener to the first anchor.

14. The system of claim 10, further comprising a setting device operative to set jaws of the chucks for attaching the anchors to the piles.

15. The system of claim 14, wherein the strand chuck setting device comprises a setting component and a hydraulic actuator operative to move the setting component.

16. A method for splicing prestressed concrete piles comprising:

using strand locking devices to attach first and second anchors to respective strands of first and second piles; and

securing the first and second anchors to each other.

17. The method of claim 16, wherein, in using the strand locking devices, the strand locking devices are engaged with the strands by a hydraulic ram.

18. The method of claim 17, wherein the hydraulic ram facilitates engagement of the strand locking devices simultaneously with the strands of the first and second piles.

19. The method of claim 16, wherein, in securing the first and second anchors, the anchors are secured to each other using mechanical fasteners.

20. The method of claim 16, wherein the securing comprises:

positioning the piles in an end-to-end relationship such that the first and second anchors are adjacent each other;

mounting a guide pin to the first anchor;

positioning the piles such that the guide pin aligns with a corresponding hole in the second anchor;

removing the guide pin; and

inserting a mechanical fastener through the hole in the second anchor to secure the anchors in position relative to each other.