ANCHOR FOR USE IN CONCRETE STRUCTURE

Description

This application claims priority to U.S. provisional application Ser. No. 63/711,455 entitled ANCHOR FOR USE IN CONCRETE STRUCTURE filed on Oct. 24, 2024, the entire contents of which are hereby incorporated by reference.

The present invention is directed to an anchor for use in a concrete structure, and more particularly, to such an anchor for use in prestressed concrete structure.

BACKGROUND

Anchors are often used in concrete structures to provide a location at which the concrete structure can be gripped, lifted and/or moved. However many existing anchors can be difficult to properly position, can involve significant labor to install, and/or may not be sufficiently anchored in place to accommodate the shape and weight of the associated concrete structure.

SUMMARY

In one embodiment the present invention is directed to an anchor that can be easily positioned, and/or easily installed and/or be strongly anchored in place. More particularly, in one embodiment the system is a system including an anchor having a generally “U” shaped body with a base and a pair of parallel legs. The anchor further includes a plurality of recesses spaced along at least one of the legs.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a upper perspective view of part of a concrete structure, with an anchor coupled thereto;

FIG. 2 is a side cross section taken along line 2-2 of FIG. 1;

FIG. 3 is a top view the anchor and tensioning members of the concrete structure of FIG. 2;

FIG. 4 is a top view the anchor and tensioning members of the concrete structure of FIG. 2, shown in conjunction with a void former;

FIG. 5 is a side view of the anchor of FIG. 2;

FIG. 6 is a side view of an alternate embodiment of the anchor of FIG. 5;

FIG. 7 shows the concrete structure and anchor of FIG. 2, with the anchor in a different rotational position;

FIG. 8 is a top view of the anchor and tensioning members of the concrete structure of FIG. 7;

FIG. 9 is a top view of the anchor and tensioning members of the concrete structure of FIG. 7, shown in conjunction with a void former;

FIG. 10 shows the concrete structure and anchor of FIG. 7, with the anchor in a different rotation position and with a different arrangement of tensioning members;

FIG. 10A is a detail view of the area indicated in FIG. 10;

FIG. 11 is a top view of anchor and the tensioning member of the concrete structure of FIG. 10;

FIG. 12 is a top view of anchor and the tensioning member of the concrete structure of FIG. 10, shown in conjunction with a void former;

FIG. 13 is an exploded perspective view of the void former of FIG. 4, shown in conjunction with part of an associated anchor;

FIG. 14 is an assembled view of the void former and anchor of FIG. 13;

FIG. 15 shows a form with an anchor member, void former and tensioning members positioned therein; and

FIG. 16 shows the form of FIG. 15 filed with concrete.

DETAILED DESCRIPTION

With reference to FIGS. 1 and 2, in one embodiment the system 10 includes or can be used with a concrete structure, generally designated 12. In the illustrated embodiment the concrete structure 12 includes or takes the form of a double tee concrete structure that is generally “T” shaped in end view/cross section. The concrete structure 12 in this case has a platform 14 forming the upper part of the “T” wherein an upper surface 30 of the concrete structure 12/platform 14 is generally flat and planar. The concrete structure 12 can further include a web 16 oriented perpendicular to the platform 14 forming the vertical leg of the “T.” In one embodiment the concrete structure 12 can be a structural pre-stressed precast concrete element including one or more tensioning members or reinforcing members 18 formed therein. The concrete structure 12 can be used as a structural member and provide relatively long spans, and be used in for example parking structures, large span bridges and roadways, roof, floors, heavy load applications, and the like.

With reference to FIG. 2, the tensioning members 18, in the illustrated embodiment, are parallel, spaced apart structures. The tensioning members 18 can be made of a variety of materials and take a variety of forms, such as metal wires, or tendons, straps or bars made of high tensile steels, carbon fiber or aramid fibers, that are, in one case, elongated bodies with a uniform or generally uniform cross section along their lengths, and are generally cylindrical in the illustrated embodiment. The tensioning members 18 can be prestressed tensioning members 18 that are placed under tension while the concrete portion of the concrete structure 12 is poured and allowed to cure. In another case, rather than being prestressed, the tensioning members 18 can be post-tensioned and placed in tension after the concrete is poured and/or cured.

In the embodiment of FIG. 2 the concrete structure 12 includes three rows and two columns of tensioning members 18 in a double-strand pattern, positioned in the web 16 of the concrete structure 12 and oriented parallel to a length of the concrete structure 12, and parallel to the upper surface 30 of the platform 14. However the number, arrangement and positioning of the tensioning members 18 can vary as desired.

The system 10/concrete structure 12 can include an anchor 20 embedded therein or coupled thereto to aid in gripping, lifting and moving the concrete structure 12. With reference to FIGS. 2, 5 and 6, the anchor 20 can have a generally “U” shaped body 22 having a base 24 and a pair of spaced-apart, parallel legs 26 having the same length, in one case. The anchor 20 can be made of a relatively wide range of materials, including relatively rigid, stiff and strong materials, including metal. The base 24 can be curved and/or angled, and is generally semicircular in one case. The base 24 can also be at least partially positioned in a void, recess or gap 28 (collectively termed a “void” herein) formed in the upper surface 30 of the concrete structure 12, as shown in FIGS. 1 and 2.

In this manner the void 28 provides access to the anchor 20/base 24 such that a hook, clasp or the like, for example from a crane, hoist, excavator or the like, can be passed through/underneath the base 24 to enable the concrete structure 12 to be gripped, lifted and moved by the anchor 20. It should be noted that although FIG. 1 shows the concrete structure 12 having only a single anchor 20, any number of anchors 20 can be positioned in the concrete structure 12 as desired. The anchor 20/base 24 can, in one case, be entirely recessed below the upper surface 30 of the concrete structure 12/platform 14 to ensure the anchor 20/base 24 does not protrude upwardly and does not catch on items, and also enabling other items to be stacked on the platform 14.

The anchor 20 can have a generally cylindrical body 22 with a constant thickness/diameter/cross sectional area, where the anchor 20/body 22 is in one case bent or formed into the “U” shape. One or each leg 26 of the anchor 20/body 22 can have a plurality of notches/recesses/cutouts 32 (collectively termed “recesses” herein) spaced there along. Each recess 32 can have a smaller or reduced diameter/thickness/cross sectional area as compared to the remainder of the anchor 20/body 22 (e.g. those portions of the anchor 20/body 22 where the recesses 32 are not located, or the body diameter). In one case each recess 32 may not be angled (e.g. a plane of the upper and/or lower circumferential surfaces 36 of the recess 32 may be oriented perpendicular to the central axis of the associated leg 26). In one case the recesses 32 may be isolated from each other; in other words the recesses 32 may not be continuous or communicate with each other in the manner of a threaded/running recess. Thus each recess 32 may not be a running thread or part of a running thread, and can be entirely spaced apart from, and not in contact/communication with any adjacent recesses 32. In addition each recess 32 (or a central axis thereof) can be oriented at an angle perpendicular to the central axis of the associated leg 26.

In addition, each recess 32 can extend continuously 360 degrees (e.g. entirely circumferentially) around the associated anchor 20/body 22. This ensures that the recesses 32 can provide the functionality outlined below, regardless of the positioning of the anchor 20. Thus the anchor 20/body 22 may lack any ridges or ribs, that extend longitudinally along the length of the legs 26, at least in the area of the recesses 32. Stated differently the anchor 20/body 22 may lack any ridges or ribs that intersect with, protrude at least partially into, or extend entirely across the height of one or more, or all, of the recesses 32. In other cases, each recess 32 can extend at least about 180 degrees in one case, or at least about 90 degrees in another case, about the associated anchor 20/body 22, which may be sufficient for each recess 32 to receive a tensioning member 18 therein, as will be described in greater detail below.

In the case where the legs 26 are cylindrical (e.g. having a circular cross section), the recesses 32 can be annular, and the associated portions for the legs 26 can have a reduced diameter/cross sectional area compared to the remainder of the anchor 20/body 22. Stated differently, the anchor 20/body 22/legs 26 can have the same cross sectional size and shape along its entire length (or some, or along a majority of its length) except for where the recesses 32 are located (or can have the same cross sectional size and shape along a majority of its length (e.g. greater than 50% of its length in one case, or greater than 75% of its length in another case, or greater than 90% of its length in yet another case), except for where the recesses 32 are located).

The portions of the anchor 20/body 22 lacking the recess 32, particularly those portions located between adjacent recesses 32, can be termed segments 34. Each recess 32 can be separated from any adjacent recesses 32 by a segment 34 of the anchor 20/body 22. In the illustrated embodiment each recess 32 includes or is defined by a transition surface 36 oriented in a radial plane (e.g. each transition surface 36 is oriented in a plane that forms a ninety degree angle relative to a central axis of the associated leg 26). However if desired the transition surface 36 can be formed at an angle relative to a radial plane (e.g. form a more gradual transition angle), or be a curved surface, etc.

In the illustrated embodiment, each segment 34 extends about the same (axial) length as the (axial) length of a recess 32. In one case each segment has 34 a length that is within +/−50% (e.g. between 50% and 150%) of a length of one or each adjacent recess 32, and vice versa. As can be seen, the recesses 32 can collectively extend a significant length of the associated leg 26. In one case the recesses 32 collectively extend at least about 15 percent of a length of the leg 26 in one case, or at least 25 percent in another case and/or less than about 75 percent of a length of the leg 26. In one case, each recess 32 has a diameter (thickness) and/or cross sectional area between about 50% and about 95% of a diameter (thickness) and/or cross sectional area of the body segments 34 (and/or of a diameter (thickness) of a portion of the leg 26 at a location other than the location of the recesses 32).

With reference to, for example, FIG. 2, the recesses 32 enable the legs 26/anchor 20 to move closer to the (vertical) center of the concrete structure 12/web 16, and thus further away from the associated outer surface 40. In particular, it can be desired for all portions of the anchor 20 to be sufficiently spaced from the outer surface 40 to provide for maximum “concrete coverage”—e.g. sufficient spacing from the outer surface 40. With reference to FIG. 2 the concrete coverage/spacing for the anchor 20 is defined by dimension A, which is the shortest distance from the anchor 20 to the outer surface 40 of the concrete structure 12. In certain cases, relevant standards require a concrete coverage of at least 0.75 inches. Thus in some cases the anchor 20 is entirely spaced away from the outer surface 40 of the concrete structure 12 by at least 0.75 inches.

The recesses 32, and their interaction with the tensioning members 18, help to ensure sufficient concrete coverage is provided. In particular, the tensioning members 18 can fit into associated recesses 32 (see e.g. FIG. 10A), which enables the legs 26 of the anchor 20 to move inwardly, in the direction of the reduced thickness of the recesses 32, thereby moving the legs 26 inwardly away from the outer surface 40, by a distance equal to the depth of the recesses 32. For example, with reference to FIG. 2, the anchor 20 can be slightly pivoted about vertical axis B in the direction of arrow C until each tensioning member 18 is received in an associated recess 32. Thus the recesses 32 can have a spacing, or a multiple thereof, that corresponds to the vertical distance/spacing between adjacent tensioning member 18. In some cases during installation/assembly (e.g. in the step of FIG. 15, described in greater detail below) the installer may need to slightly move/jiggle the anchor 20 in the vertical direction, up and down, to ensure the tensioning members 18 are received in the recesses 32.

When the anchor 20 is pivoted about the vertical axis B, the legs 26 move inwardly, and concrete coverage is increased (or, alternatively, the thickness of the web 16 can be correspondingly reduced, providing material saving and weight reduction). In addition, when the tensioning member(s) 18 are received in the recesses 32, the tensioning members 18 and anchor 20 overlap in a direction perpendicular to the central axis of the legs 26 and/or overlap in the radial direction (relative to the central axis of the legs 26; that is, they overlap in the right-to-left direction of FIG. 2 (see also FIG. 10A)) which helps secure the anchor 20 to the tensioning members 18, and more securely retains the anchor 20 in place in the concrete structure 12.

Thus in one case each recess 32 has an axial length that is equal to or greater than a thickness (or diameter) of the associated tensioning member 18, so that the associated tensioning member 18 can be received therein. In one case each recess 32 has an axial length that is less than 125% greater than the thickness (or diameter) of the associated tensioning member(s) 18 to avoid unduly compromising the strength of the anchors 20. A common diameter for tensioning members is 0.5 inches, and thus in one case each recess 32 can have a length of between 0.25 and 0.75 inches, and a length of about 0.5 inches in one case. The depth of each recess 32 can vary as desired, but should be sufficiently deep to provide the benefits described above, but not so deep as to compromise the strength of the anchor 20. In certain cases the legs 26 are spaced apart a distance between 2.5 inches and 3 inches, and more particularly are spaced apart a distance of 2.75 inches, which provides sufficient spacing for the legs 26 to be able to span the typical spacing of the tensioning members 18.

In one case the recesses 32 are arranged and configured such that the depth of the recesses 32 varies gradually, progressively and/or in a step-wise manner along the length of the legs 26. In one case the depth of the recesses 32 is varied such that the recesses 32 have a shallower depth at areas at or adjacent to the base 24, and the depth generally increases, moving toward the distal end of the leg 26 opposite the base 24. Thus the recesses 32 can be configured such that a depth of the recesses 32 generally increases with a distance nearer a distal end of the leg 26.

In the embodiment of FIG. 5, the recesses 32a have a relatively shallow depth, the recesses 32b have a deeper depth, and the recesses 32c have an even deeper depth. In one case the legs 26/segments 34 has a thickness/diameter of 0.75 inches, the recesses 32a have a thickness/diameter of 0.68 inches, the recesses 32b have a thickness/diameter of 0.64 inches, and the recesses 32c have a thickness/diameter of 0.59 inches. Thus in this case at least one recess (e.g. recesses 32c) located nearer a distal end of the leg 26 has a greater depth than at least one recess (e.g. recesses 32a and/or 32b) located further from the distal end of the leg 26. Stated differently, the depth of a given recess 32 (e.g. recess 32a) is equal to or less than a depth of a recess 32 of the leg 26 (e.g. recess 32b and/or 32c) located between the given recess (e.g. recess 32a) and a distal end of the leg 26. The relatively deeper recesses 32b, 32c help to promote concrete anchorage and reduce concrete coverage at the distal end of the legs 26, where the web 16 of the concrete structure 12 tapers to a narrower depth, while the relatively shallower recesses 32a, 32b help to ensure sufficient strength of the anchor 20.

In one case the anchor 20 can have a length between 12 inches and 28 inches. In the embodiment of FIG. 5, the anchor 20 can have a length of 23 inches, the legs 26 can be spaced apart a distance of 4.25 inches. The anchor of FIG. 5 can be rated for use with relatively heavy concrete structures, such as up to 10 tons in one case. In the embodiment of FIG. 6, the anchor 20 can have a length of 18 inches, the legs 26 can be spaced apart a distance of 2.75 inches. The anchor of FIG. 6 can be rated for use with relatively lighter concrete structures, such as up to 8 tons in one case. In the embodiment of FIG. 6, the anchor 20 has recess 32a, 32b having only two different depths, instead of the recesses 32a, 32b, 32c having three different depths as shown in the embodiment of FIG. 5. However it should be understood that the anchors 20 can have recesses 32 with any number of differing depths, including in one case where each recess 32 has a different depth from every other recess 32. In one case each leg 26 has at least two recesses 32, or at least five recesses 32 in another case, or at least ten recesses 32 in another case, and less than one hundred recesses 32 in one case, and less than fifty recesses 32 in yet another case.

In the embodiment of FIGS. 2-4, the concrete structure 12 includes two columns and three rows of tensioning members 18, and the anchor 20 is positioned about the tensioning members 18 such that the tensioning members 18 are positioned between the legs 26. In addition, in this embodiment the anchor 20/legs 26 are in contact with the outer surfaces of the tensioning members 18, and the tensioning member 18 are received in associated recesses 32. Thus in this embodiment the concrete structure 12 can include at least two parallel, spaced apart tensioning members 18, and both tensioning members 18 are positioned between the legs 26 of the anchor 20.

In the embodiment of FIGS. 7-9, the concrete structure 12 again includes two columns and three rows of tensioning members 18, and the anchor 20 is positioned within the tensioning members 18 such that the anchor 20/legs 26 are positioned between the tensioning members 18. Thus in this embodiment the anchor 20 is rotated (90°) about axis B from the position shown in FIG. 2. In this embodiment the concrete structure 12 can include at least two parallel, spaced apart tensioning members 18, and both legs 26 of the anchor 20 are positioned between the two tensioning members 18. In the illustrated embodiment the anchor 20/legs 26 are in not contact with the outer surfaces of the tensioning members 18, but if desired the anchor 20 could be rotated about axis B in the direction of arrow C such that the anchor 20/legs 26 are in contact with the inner surfaces of the tensioning members 18.

In the embodiment of FIGS. 7-9 the recesses 32 do not engage the tensioning members 18 and/or the anchor 20 is positioned inside the tensioning members 18. The configuration of FIGS. 7-9 can be used when the anchor 20 and/or tensioning members 18 are configured such that that anchor 20 cannot span/be positioned outside the tensioning members 18, or where it is otherwise desired not to have the anchor 20 span/be positioned outside the tensioning members 18. For example, in some cases it may be desired for the anchor 20 to not span/be positioned outside the tensioning member 18 if insufficient concrete coverage would be provided. The configuration shown in FIGS. 7-9 illustrates the flexibility of use and positioning of the anchor 20 in which the anchor 20 can be positioned within the tensioning members 18 and still operate as a functional anchor 20.

In the embodiment of FIGS. 10-12, the concrete structure 12 includes one column and three rows of tensioning members 18 in a single strand pattern. In this embodiment the anchor 20 is positioned about the tensioning members 18 such that the tensioning members 18 are positioned between the legs 26, and the anchor 20/legs 26 are in contact with the opposed outer surfaces of the tensioning members 18. Thus in this embodiment both legs 26 of the anchor 20 are in contact with each tensioning member 18 on opposite sides of that tensioning member 18.

In order to form the concrete structure 12 with reference to FIG. 15, a form 41 can be provided, defining a void 42 in the shape of the concrete structure 12 to be formed. The tensioning members 18 and the anchor 20 are then positioned in the form 41, and can be positioned/suspended in the desired position by various wires and/or other positioning structures (not shown). In the embodiment of FIG. 15, the anchor 20 is positioned in the configuration shown in FIGS. 2-4, and the anchor 20 can be rotated about the axis B in the direction of arrow C as described above, to provide sufficient concrete coverage in the direction of dimension A. Of course, the anchor 20 and/or tensioning members 18 can vary from that shown in FIG. 15 to provide the configurations shown in FIGS. 7-9 and 10-12 respectively, or other configurations.

In order to form the void 28, a liquid/fluid tight void former 44 is positioned about a distal end of the anchor 20, and in particular about at least part of the base 24, and optionally around at least part of the legs 26. With reference to FIG. 13, the void former 44 can be generally semicircular in side view, having a flat upper surface 46 and a curved/arcuate lower surface 48 that forms the void 28. In the illustrated embodiment the void former 44 includes a pair of adapters 50 that fit into a central opening 52 of the void former 44, and are positioned on either side of the anchor 20/base 24, to secure the void former 44 to the anchor 20/base 24 in a secure and, if desired, fluid/liquid tight manner.

The adapters 50 can be used to adapt a standard void former for use with the anchor 20, but the adapters 50 are optional and instead a customized void former for use with the anchor 20 can be implemented, in which case the adapters 50 may not be needed. With reference to FIG. 14, the void former 44 can be oriented perpendicular (with regard to its longest dimension) to a plane in which the anchor 20 is aligned. When the void former 44 is coupled to the anchor 20, the void former 44 can be sufficiently rigidly coupled that the void former 44 rotates along with rotation of the anchor 20, as can be seen in comparing FIGS. 4, 9 and 12.

Returning to FIG. 15, once the form 41 is provided, and the tensioning members 18, anchor 20 and void former 44 positioned therein the desired manner, concrete 54 in its liquid/uncured form can then be poured in the void 42/form 41. The tensioning members 18 and anchor 20 remain in place and are immersed in the poured concrete 54, remaining in the finished poured concrete structure 12 when cured. The portions of the anchor 20/base 24 received in the void former 44 are fluidly isolated from, and thus not immersed in, concrete 54. After pouring and curing, the form 41 can be removed and the concrete structure 12 is released from the form 41. The void former 44 can then be removed, resulting in the structure 12 shown in FIGS. 1 and 2. The resultant structure 12 thus has the anchor 20 embedded therein. The anchor 20 can be used for lifting, moving and positioning the concrete structure 12, and provides improved anchoring and/or concrete clearance characteristics as outlined above.

Having described the invention in detail and by reference to the various embodiments, it should be understood that modifications and variations thereof are possible without departing from the scope of the claims of the present application.