CENTERING SLEEVE FOR A PILE SHOE

Description

BACKGROUND OF THE INVENTION

The present invention relates to a centering sleeve for a pile shoe to be disposed on a driven pile, a pile shoe on which such a centering sleeve is or can be disposed, and a driven pile on which such a pile shoe and such a centering sleeve are disposed.

Driven piles are used in the construction industry to create pile foundations. The individual driven piles, which are mostly made of ductile cast iron and have predetermined lengths of, for example, five meters, are inserted into one another to create a pile foundation, wherein a pile shoe is usually attached to the lower end (pile foot) of the first pile to be driven into the ground to facilitate the driving into the ground. To facilitate the insertion of the driven piles into one another and thus the extension of a pile foundation, the driven piles usually have a conically tapered first pile end and a second pile end formed into a socket. This means that piles can be driven into the ground one by one, allowing pile foundations of any length to be constructed quickly and cost-effectively. Driven piles of this type are usually manufactured using a centrifugal casting process with a rotating mold. This substantially creates cylindrical tubular piles that are hollow inside.

When it comes to pile foundations, a distinction is made between grouted and ungrouted pile foundations.

In grouted pile foundations, a pile shoe, the outer diameter of which is larger than the outer diameter of the driven pile, is placed on the first driven pile. This allows an annular space to be created around the driven pile during driving. During driving, a pumpable injection material (e.g. concrete mortar) is conveyed through the hollow core of the driven pile to the pile foot and pressed into the ground at the pile shoe. Thus, concrete grouting takes place at the same time as the pile is driven.

In the case of ungrouted pile foundations, which are used in particular for foundations in rock or very dense soils, a pile shoe, the outer diameter of which usually corresponds substantially to the outer diameter of the driven pile, is placed on the first driven pile. A centering sleeve is usually disposed on the pile shoe, which centering sleeve is located between the pile shoe and the driven pile when the pile shoe is attached to the driven pile and in particular ensures a good connection between the pile shoe and the driven pile. Known centering sleeves are designed to be longitudinally extended, starting from an upper end of the centering sleeve along a longitudinal axis to a lower end of the centering sleeve, and have an outer casing surface against which an inner wall of the driven pile rests when the pile shoe is attached to the driven pile.

Placing the driven pile often causes difficulties with conventional pile shoes with centering sleeves. It can happen that the driven pile cannot be placed centrally and/or vertically on the pile shoe, which can cause problems during the driving process.

SUMMARY OF THE INVENTION

It is the object of the invention to avoid the disadvantages described above and to provide a centering sleeve which is improved compared to the prior art. Furthermore, a pile shoe on which such an improved centering sleeve is or can be disposed, as well as a driven pile on which such a pile shoe and such a centering sleeve are disposed, are to be specified.

This object is achieved by a centering sleeve as described below, a pile shoe as described below, and a driven pile as described below.

In the centering sleeve according to the invention, a centering device projecting from the casing surface is disposed on the casing surface. The centering device projecting from the casing surface can facilitate the placement of the driven pile. In particular, this can facilitate a centric and substantially vertical placement of the driven pile.

The longitudinal axis of the centering sleeve represents a central axis of the centering sleeve, which is preferably aligned with a central axis of the driven pile in the mounting position of the centering sleeve on the pile shoe and the driven pile.

Preferably, the casing surface can be rotationally symmetrical with respect to the longitudinal axis. The longitudinal axis of the centering sleeve forms the axis of rotation. If the casing surface is not rotationally symmetrical, the longitudinal axis of the centering sleeve can represent a central axis which, in the mounting position on the pile shoe and driven pile, can be aligned with a central axis of the driven pile.

In a preferred embodiment, the casing surface along the longitudinal axis has an outer diameter that is substantially constant with respect to the longitudinal axis. However, the casing surface can also be variable along the longitudinal axis and, for example, have a conicity in relation to the longitudinal axis. For example, the outer diameter can increase towards the lower end of the centering sleeve.

According to a particularly preferred exemplary embodiment, the centering sleeve can consist of at least one plastic. The centering sleeve can be designed as an injection-molded part that is manufactured using known plastic injection molding processes. Preferably, a deformable plastic can be selected as the material for the centering sleeve, such that the centering sleeve can deform in a connection section of the centering sleeve when the driven pile is placed on the centering sleeve, thus resulting in a firm and substantially tight connection (e.g. with respect to solids such as soil or sand) with the driven pile.

Preferably, the centering device can comprise at least one fin running around the longitudinal axis. In other words, when looking at the centering sleeve from above, the fin runs along the circumference of the outer surface.

In this case, the at least one circumferential fin can preferably project substantially radially from the casing surface with respect to the longitudinal axis, wherein the at least one circumferential fin has a radial extension starting from the casing surface up to an outer end of the at least one circumferential fin.

According to a preferred embodiment, the at least one circumferential fin can consist of at least one plastic.

Preferably, an elastically deformable plastic can be selected as the material for the at least one circumferential fin. In other words, the plastic used preferably has a certain elasticity so that the fin is flexible enough to conform to the inner wall of the driven pile when the driven pile is placed on the centering sleeve. The centering sleeve together with the at least one circumferential fin can be designed as an integral injection-molded part. Since pile tube foundations can be constructed under a wide range of weather and temperature conditions, it is preferable to use a plastic whose properties are substantially constant in a temperature range from approximately −20° C. to approximately +40° C., in particular with regard to the flexibility of the fins.

In general, an elastomer, particularly preferably a thermoplastic polyester elastomer, can be used as the plastic for the centering sleeve and/or the at least one circumferential fin. For example, the plastic from DuPont called DuPont™ Hytrel® 6356 can be used. This plastic has a nominal hardness of 63D (“Shore D Hardness, max” according to ISO 7619-1) and can be processed using many conventional thermoplastic processing techniques, such as injection molding and extrusion.

Preferably, the at least one circumferential fin can be disposed in the region of the upper end of the centering sleeve. When the driven pile is placed on the centering sleeve, this is the end facing the driven pile. The at least one circumferential fin facilitates a centric and substantially vertical placement of the driven pile.

In a preferred exemplary embodiment, the at least one circumferential fin can comprise multiple fin segments, wherein two adjacent fin segments are disposed at a spacing from one another, wherein preferably the fin segments are disposed uniformly along a circumference of the casing surface. In other words, the circumferential fin consists of fin segments that are disposed at a spacing from one another along the circumference of the casing surface. Each fin segment has a radial extension from the casing surface up to an outer end of the respective fin segment, wherein preferably the radial extensions of all fin segments are substantially equal. By designing the circumferential fin as spaced-apart fin segments, the shaping of the outer ends of the fin segments to the inner wall of the driven pile can be facilitated when the driven pile is placed on the centering sleeve.

In this case, preferably at least one fin segment, preferably all fin segments, can have a recess or notch, wherein the recess or notch is preferably disposed substantially centrally. The recess or notch can extend to the casing surface, whereby the fin segment can be divided into multiple components. The recess or notch can, for example, be substantially U- or V-shaped. This in turn facilitates molding the outer ends of the fin segments onto the inner wall of the driven pile when the driven pile is placed on the centering sleeve. In particular, this can prevent unwanted wrinkling when molding to the inner wall of the pile.

According to a particularly preferred embodiment, the centering device can comprise a plurality, preferably two to ten, circumferential fins along the longitudinal axis. This means that, when the driven pile is placed on the centering sleeve, the driven pile can be centered and guided during and along the entire placement process.

In this case, the circumferential fins can preferably project substantially radially from the casing surface with respect to the longitudinal axis, wherein the at least one circumferential fin has a radial extension starting from the casing surface up to an outer end of the at least one circumferential fin. Preferably, the radial extensions of the circumferential fins can be different. This means that one centering sleeve can be used for multiple different pile tube inner diameters. Different pile tube inner diameters can arise, for example, due to manufacturing tolerances. However, driven piles with the same pile tube outer diameter can also have different wall thicknesses for different load-bearing capacities, which can also result in different pile tube inner diameters.

Each circumferential fin can in turn comprise multiple spaced-apart fin segments, wherein the fin segments of a circumferential fin are preferably disposed uniformly along a circumference of the casing surface. The fin segments of a circumferential fin can also have recesses or notches, which are preferably disposed substantially centrally and are preferably substantially U- or V-shaped.

In a preferred embodiment, at least one support structure for reinforcing the centering sleeve is disposed on an inner wall of the centering sleeve.

Preferably, the support structure can extend from an upper end of the centering sleeve along a section of the elongated centering sleeve.

Preferably, the support structure can comprise support struts, wherein the support struts extend substantially radially to the inner wall of the centering sleeve with respect to the longitudinal axis. The support struts can, for example, have a substantially U-shaped cross-section.

According to a preferred exemplary embodiment, the centering sleeve has a sleeve section and an adjoining connection section along the longitudinal axis, wherein the sleeve section has the casing surface, wherein the connection section comprises at least one connecting device for connecting the centering sleeve to the pile shoe.

Preferably, the at least one connecting device is designed as a recess in the connection section, wherein preferably the at least one recess is designed to correspond to at least one connection device of the pile shoe. The at least one recess can preferably be designed in the form of a through hole. For example, the recess can be designed as a substantially rectangular through hole into which a correspondingly shaped connection device of the pile shoe can engage when the centering sleeve is placed on a pile shoe to connect the centering sleeve to the pile shoe in a form-fitting manner.

In a preferred embodiment, the connection section can have at least one substantially conical outer surface, wherein an outer diameter of the at least one outer surface increases towards the longitudinal axis. This results in a ramp-shaped or frustoconical abutting surface in the form of the at least one substantially conical outer surface for a driven pile to be placed on the centering sleeve, whereby the driven pile is clamped or pressed against the connection section of the centering sleeve when the driven pile is placed on the centering sleeve, such that a firm and also substantially tight connection between the driven pile and the centering sleeve is achieved. A conical design of the outer surface also makes it possible to compensate for different wall thicknesses of the driven piles.

Preferably, the connection section can have a first outer surface and an adjoining second outer surface in the direction of the longitudinal axis, wherein the first outer surface and the second outer surface are substantially conical, wherein the conicity of the first outer surface is greater than the conicity of the second outer surface. In other words, the first outer surface slopes more gently in the direction of the longitudinal axis than the second outer surface, or the second outer surface slopes more steeply than the first outer surface. The first outer surface can be used to facilitate the centric placement of a driven pile. When a driven pile is placed, the pile first hits the first outer surface and when it is placed further in the direction of the longitudinal axis, the steeper second outer surface means that it can adapt well to the inner wall of the driven pile. In particular, when using a plastic centering sleeve, the pile shears off the outer surface when it is set into place. This placement and the associated shearing is facilitated by the steeper second outer surface. Overall, this can result in a firm and substantially tight connection between the driven pile and the centering sleeve, particularly in the area of the second outer surface, such that no unwanted contamination (e.g. soil, sand) can penetrate into the interior of the driven pile, although it is possible that fluids such as water or gas can still penetrate into the interior of the driven pile (it is therefore possible that the connection is not hermetically sealed).

Preferably, the at least one connecting device is formed in the second outer surface.

According to another exemplary embodiment, the connecting portion has at least one substantially conical inner surface, wherein an inner diameter of the at least one inner surface increases towards the longitudinal axis. This facilitates placing the centering sleeve centrically on a suitably designed pile shoe.

Preferably, the at least one inner surface can comprises multiple, preferably two to eight, inner segments along a circumferential direction with respect to the longitudinal axis.

Preferably, the at least one inner surface comprises four inner segments along the circumferential direction, wherein two opposing first inner segments in the region of the lower end of the centering sleeve have a first radius of curvature with respect to the longitudinal axis, wherein two opposing second inner segments in the region of the lower end of the centering sleeve have a second radius of curvature with respect to the longitudinal axis, wherein the second radius of curvature is greater than the first radius of curvature. By providing different radii of curvature, a preferred orientation of the centering sleeve in a direction of rotation about the longitudinal axis of the centering sleeve relative to the pile shoe can be determined when placing the centering sleeve on a correspondingly designed pile shoe. Preferably, a respective connecting device (e.g. a through hole with a shape corresponding to corresponding connection devices of the pile shoe) can be formed in each of the second inner segments.

Protection is also sought for a pile shoe for a substantially tubular, in particular hollow-cylindrical, driven pile, wherein a centering sleeve of the type described above is or can be disposed on the pile shoe.

The pile shoe can preferably be made of ductile cast iron and manufactured by means of a known casting process.

Preferably, the pile shoe comprises a ramming structure for facilitating ramming of the pile shoe in a ramming direction into a subsoil. In the position of use of the pile shoe on a driven pile, the driving direction substantially corresponds to the direction in which the driven pile with the pile shoe attached thereto is driven into the subsoil.

Preferably, the ramming structure comprises a plurality, preferably two to eight, particularly preferably four, ramming ribs and a pile shoe plate, wherein the ramming ribs project from the pile shoe plate in the ramming direction, starting from the pile shoe plate. When the centering sleeve is placed on the pile shoe, the longitudinal axis of the centering sleeve preferably runs substantially in the driving direction.

In a preferred embodiment, the ramming ribs are disposed in a cross-shaped or star-shaped manner on the pile shoe plate, wherein the ramming ribs are preferably designed to converge towards one another in the driving direction. In other words, the ramming ribs can have outer sides that run obliquely in relation to the pile shoe plate, with imaginary extensions of their outer sides converging to a point.

Preferably, the outer sides of the ramming ribs are at an angle of approximately 20° to 60° to the pile shoe plate. For example, “pointed” and “flat” pile shoes can be provided, wherein the pointed pile shoes have the outer sides of the ramming ribs at an angle of about 20° to 40° (preferably about) 30° to the pile shoe plate and the flat pile shoes have the outer sides of the ramming ribs at an angle of about 30° to 60° (preferably about) 45° to the pile shoe plate.

According to a preferred exemplary embodiment, the pile shoe can have a substantially flat support surface for setting up the pile shoe on a subsoil. The contact surface can be formed by correspondingly flat ends of the ram ribs.

In a particularly preferred embodiment, the pile shoe comprises a connection device disposed on the ramming structure, wherein the connection device extends from the ramming structure counter to the ramming direction, wherein the connection device comprises a connection section and an adjoining guide section against the ramming direction.

Preferably, the connection section comprises at least one connection device for connecting the pile shoe to the centering sleeve.

In this case, the at least one connection device can be designed as a, preferably substantially nose-shaped, projection, wherein the at least one projection is preferably designed to correspond to at least one connecting device of the centering sleeve. If the at least one connection device of the pile shoe is designed as a substantially nose-shaped projection and the at least one connecting device of the centering sleeve is designed as a through hole, for example a substantially rectangular one, the nose-shaped projection can engage in the through hole when the centering sleeve is placed on the pile shoe. The centering sleeve can be snapped onto the pile shoe or locked into place on the pile shoe, resulting in a firm, positive connection between the centering sleeve and the pile shoe.

According to a preferred embodiment, the connection section can have at least one substantially conical outer wall, wherein a diameter of the at least one outer wall increases in the ramming direction. If a connection section of the centering sleeve also has a correspondingly conical inner surface, centric placement of the centering sleeve on the pile shoe can be facilitated by guiding the inner surface of the connection section of the centering sleeve centrally along the outer wall of the connection section of the pile shoe when the centering sleeve is placed thereon.

Preferably, the at least one outer wall comprises multiple, preferably two to eight, connection segments along a circumferential direction with respect to the ramming direction.

According to another exemplary embodiment, the at least one outer wall can comprise four connection segments along the circumferential direction, wherein two opposing first connection segments have a first connection curvature radius with respect to the ramming direction, wherein two opposing second connection segments have a second connection curvature radius with respect to the ramming direction, wherein the second connection curvature radius is greater than the first connection curvature radius.

By providing different connecting radii of curvature, a preferred orientation of the centering sleeve in a direction of rotation about the longitudinal axis of the centering sleeve relative to the pile shoe can be determined when placing the centering sleeve on a correspondingly designed pile shoe. Preferably, a connection device (e.g. a nose-shaped projection) with a shape corresponding to corresponding connecting devices of the centering sleeve (e.g. a rectangular through hole) can be formed in each of the second connection segments.

Preferably, the guide section comprises a plurality, preferably four, guide webs disposed substantially in a cross shape, wherein preferably outer ends of the guide webs rest against an inner wall of the centering sleeve when the centering sleeve is disposed on the pile shoe. In other words, the centering sleeve can be guided and placed onto the pile shoe. In principle, the guide section could also be designed as a solid cylinder, but in order to save weight, it makes sense to design the guide section as a plurality of guide webs, the imaginary outer casing of which is substantially cylindrical.

In this case, the outer end of at least one guide web, preferably the outer ends of at least two opposite guide webs, can have a widening, wherein the widening has a curvature, wherein preferably in the case of a centering sleeve disposed on the pile shoe, the curvature is designed to correspond to the inner wall of the centering sleeve.

By producing the pile shoe from preferably ductile cast iron by means of a casting process, a ramming structure of the pile shoe and/or a connection device of the pile shoe can particularly be formed integrally with the pile shoe.

Furthermore, protection is sought for a driven pile having a pile shoe disposed on a driving end of the driven pile of the type described above, wherein a centering sleeve of the type described above is disposed on the pile shoe.

Preferably, the driven pile can be designed as a hollow cylinder, at least in the region of the driving end, wherein the centering sleeve is disposed within the driven pile, wherein the centering device rests against an inner wall of the driven pile. If the centering device of the centering sleeve has circumferential fins comprising spaced-apart fin segments, the outer ends of the fin segments can bend or mold onto the inner wall of the pile when the driven pile is placed on the centering sleeve, wherein a clamping adhesion of the fin segments to the inner wall of the pile results in an additional positive connection between the centering sleeve and the driven pile.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details and advantages of the present invention are explained in the following description with reference to the drawings, in which:

FIGS. 1a to 1h are different views of an exemplary embodiment of a proposed centering sleeve,

FIGS. 2a to 2h are different views of another exemplary embodiment of a proposed centering sleeve,

FIGS. 3a to 3f are different views of an exemplary embodiment of a proposed pile shoe,

FIGS. 4a to 4h are different views of another exemplary embodiment of a proposed centering sleeve,

FIGS. 5a to 5f are different views of a centering sleeve disposed on a pile shoe, and

FIG. 6 is a sectional view through a driven pile with pile shoe and centering sleeve disposed thereon.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1a to 1h show different views of an exemplary embodiment of a proposed centering sleeve 1. FIG. 1a shows a first side view of the centering sleeve 1. FIG. 1b shows a second side view of the centering sleeve 1 in a viewing direction that is orthogonal to the viewing direction of the first side view. FIG. 1c shows a top view of the centering sleeve 1. FIG. 1d shows a bottom view of the centering sleeve 1. FIG. 1e shows a sectional view along the section line A-A shown in FIG. 1a. FIG. 1f shows a sectional view along the section line B-B shown in FIG. 1b. FIG. 1g shows a perspective top view of the centering sleeve 1. FIG. 1h shows a perspective bottom view of the centering sleeve 1.

The centering sleeve 1 is designed to be elongated, starting from an upper end 4 of the centering sleeve 1 along a longitudinal axis L to a lower end 5 of the centering sleeve 1. The centering sleeve 1 has an outer casing surface 6 on which a centering device 7 projecting from the casing surface 6 is disposed to facilitate the placement of a driven pile 2 (not shown here).

The casing surface 6 of the centering sleeve 1 shown here is rotationally symmetrical with respect to the longitudinal axis L and has an outer diameter 8 along the longitudinal axis L that is substantially constant with respect to the longitudinal axis L.

The centering device 7 of the centering sleeve 1 shown here comprises a fin 9 which is circumferential with respect to the longitudinal axis L. In other words, the fin 9 runs along a circumference of the casing surface 6 in a top view of the centering sleeve 1 (see FIG. 1c). The circumferential fin 9 projects radially from the casing surface 6 with respect to the longitudinal axis L and has a radial extension 10 starting from the casing surface 6 to an outer end of the circumferential fin 9.

The circumferential fin 9 of the centering sleeve 1 shown here is disposed in the region of the upper end 4 of the centering sleeve 1 and comprises multiple fin segments 11. Two adjacent fin segments 11 are disposed at a spacing from one another. The fin segments 11 are disposed evenly along the circumference of the casing surface 6, that is, the spaces between the fin segments 11 are substantially equal.

Each fin segment 11 has a centrally disposed recess 12, which is substantially U- or V-shaped and extends to the casing surface 6, whereby the fin segment 11 is divided into two components.

The centering sleeve 1 together with the surrounding fin 9 or its fin segments 11 consists entirely of plastic and was manufactured using a plastic injection molding process.

The centering sleeve 1 of this example has a sleeve section 17 and an adjoining connection section 18 along the longitudinal axis L, wherein the sleeve section 17 has the casing surface 6 from which the centering device 7 projects.

The connection section 18 of the centering sleeve 1 shown here comprises two connecting devices 19 for connecting the centering sleeve 1 to a pile shoe 3 (see FIGS. 5a to 5f). The two connecting devices 19 are designed as recesses in the connection section 18. The shape of the recesses corresponds to connection devices 20 of the pile shoe 3, such that a reliable connection with the pile shoe 3 can be established (see, for example, FIGS. 5a and 5c).

The connecting portion 18 has a first outer surface 21 and an adjoining second outer surface 22 in the direction of the longitudinal axis L.

The first outer surface 21 and the second outer surface 22 are each substantially conical, wherein respective outer diameters of the first outer surface 21 and the second outer surface 22 increase towards the longitudinal axis L. In the example shown, the conicity of the first outer surface 21 is greater than the conicity of the second outer surface 22, that is, the first outer surface 21 slopes more gently in the direction of the longitudinal axis L compared to the second outer surface 22, or the second outer surface 22 slopes more steeply compared to the first outer surface 21.

The connecting devices 19 are formed in the second outer surface 22 in this case.

As can be seen in particular in FIGS. 1c and 1g, a support structure 15 for reinforcing the centering sleeve 1 is disposed on an inner wall 14 of the centering sleeve 1 of this example. The support structure 15 extends from an upper end 4 of the centering sleeve 1 along a section of the elongated centering sleeve 1 (see also the sectional views in FIGS. 1e and 1f) and comprises three support struts 16 which, with respect to the longitudinal axis L, run substantially radially to the inner wall 14 of the centering sleeve 1. In the example shown, adjacent support struts 16 are disposed at an angle of approximately 120° to one another, starting from a center point of the support structure 15 (through which the longitudinal axis L of the centering sleeve 1 runs). The support struts 16 have a substantially U-shaped cross-section and are open downwards (that is, in the direction of the longitudinal axis L).

As can be seen in particular in FIGS. 1d and 1h, the connecting portion 18 of the centering sleeve 1 of this example has a substantially conical inner surface 23, wherein an inner diameter of the inner surface 23 increases towards the longitudinal axis L.

Along a circumferential direction with respect to the longitudinal axis L, the inner surface 23 comprises multiple inner segments 24, 25. Specifically, the inner surface 23 shown here comprises four inner segments 24, 25 along the circumferential direction, wherein two opposing first inner segments 24 in the region of the lower end 5 of the centering sleeve 1 have a first radius of curvature 26 with respect to the longitudinal axis L, and two opposing second inner segments 25 in the region of the lower end 5 of the centering sleeve 1 have a second radius of curvature 27 with respect to the longitudinal axis L. In this example, the second radius of curvature 27 is larger than the first radius of curvature 26.

FIGS. 2a to 2h show different views of another exemplary embodiment of a proposed centering sleeve 1. FIG. 2a shows a first side view of the centering sleeve 1. FIG. 2b shows a second side view of the centering sleeve 1 in a viewing direction that is orthogonal to the viewing direction of the first side view. FIG. 2c shows a top view of the centering sleeve 1. FIG. 2d shows a bottom view of the centering sleeve 1. FIG. 2e shows a sectional view along the section line C-C shown in FIG. 2a. FIG. 2f shows a sectional view along the section line D-D shown in FIG. 2b. FIG. 2g shows a perspective top view of the centering sleeve 1. FIG. 2h shows a perspective bottom view of the centering sleeve 1.

The centering sleeve 1 shown here corresponds to the centering sleeve 1 of FIGS. 1a to 1h with the difference that the centering device 7 comprises not only one but multiple circumferential fins 9. For improved clarity, in FIGS. 2a to 2h, not all features but only the differences to FIGS. 1a to 1h are marked with reference symbols and reference symbol lines.

The centering device 7 of the centering sleeve 1 shown here comprises four circumferential fins 9 along the longitudinal axis L. The circumferential fins 9 project substantially radially from the casing surface 6 with respect to the longitudinal axis L, wherein each of the circumferential fins 9 has a radial extension 10 starting from the casing surface 6 up to an outer end of the respective circumferential fins 9. The radial extensions 10 of the circumferential fins 9 shown here are different, whereby the centering sleeve 1 can be used for multiple different pile tube inner diameters.

In this example, each circumferential fin 9 comprises multiple spaced-apart fin segments 11 which are evenly disposed along a circumference of the casing surface 6 (see, for example, FIGS. 2c and 2g). The fin segments 11 of the circumferential fins 9 each have a recess 12 or a notch 13, which is disposed substantially centrally and is substantially U- or V-shaped. The fin segments 11 of the uppermost circumferential fin 9 (in the region of the upper end 4 of the centering sleeve 1) each have a centrally disposed recess 12, which is substantially U- or V-shaped and extends to the casing surface 6, whereby the respective fin segment 11 is divided into two components. The fin segments 11 of the circumferential fins 9 each have a notch 13, which is disposed substantially centrally and is substantially U- or V-shaped.

FIGS. 3a to 3f show different views of an exemplary embodiment of a proposed pile shoe 3. FIG. 3a shows a first side view of the pile shoe 3. FIG. 3b shows a second side view of the pile shoe 3 in a viewing direction that is orthogonal to the viewing direction of the first side view. FIG. 3c shows a bottom view of the pile shoe 3. FIG. 3d shows a top view of the pile shoe 3. FIG. 3e shows a perspective bottom view of the pile shoe 3. FIG. 3f shows a perspective top view of the pile shoe 3.

A centering sleeve 1 according to FIGS. 1a to 1h or 2a to 2h can be disposed on the pile shoe 3, for example, and a driven pile 2 can subsequently be placed on the pile shoe 3 with the centering sleeve 1 disposed thereon.

The pile shoe 3 shown here comprises a ramming structure 28 for facilitating ramming of the pile shoe 3 in a ramming direction R into a subsoil not shown in detail. In this example, the ramming structure 28 comprises four ramming ribs 29 and a pile shoe plate 30, from which the ramming ribs 29 project in the ramming direction R. The ramming ribs 29 are disposed in a cross shape on the pile shoe plate 30 and are designed to taper towards each other in the ramming direction R. Outer sides 31 of the ramming ribs 29 are at an angle W of approximately 45° to the pile shoe plate 30.

To facilitate the installation of the pile shoe 3 on a subsoil, the pile shoe 3 has a substantially flat support surface 32, which is formed by correspondingly flat ends of the ramming ribs 29.

To facilitate the connection of the pile shoe 3 to a centering sleeve 1, the pile shoe 3 comprises a connection device 33 disposed on the ramming structure 28, which connection device extends from the ramming structure 28 against the ramming direction R. The connection device 33 comprises a connection section 34 and an adjoining guide section 35 opposite to the ramming direction R.

The connection section 34 of the pile shoe 3 shown here comprises two connection devices 20 for connecting the pile shoe 3 to a centering sleeve 1 (see FIGS. 5a to 5f). The two connection devices 20 are designed as substantially nose-shaped projections. The shape of the nose-shaped projections corresponds to connecting devices 19 of the centering sleeve 1, such that a reliable connection with the centering sleeve 1 can be established (see, for example, FIGS. 5a and 5c).

The connection section 34 of the pile shoe 3 of this example has a substantially conical outer wall 36, wherein a diameter of the at least one outer wall 36 increases in the driving direction R.

Along a circumferential direction with respect to the ramming direction R, the outer wall 36 comprises multiple connection segments 37, 38. Specifically, the outer wall 36 shown here comprises four connection segments 37, 38, wherein two opposing first connection segments 37 have a first connection curvature radius 39 with respect to the ramming direction R, and two opposing second connection segments 38 have a second connection curvature radius 40 with respect to the ramming direction R. In this example, the second connection curvature radius 40 is larger than the first connection curvature radius 39.

For an optimal connection of the pile shoe 3 with the centering sleeve 1, the conicity and first connection radius of curvature 39 of the first connection segments 37 of the pile shoe 3 correspond to the conicity and first radius of curvature 26 of the first inner segments 24 of the centering sleeve 1, and the conicity and second connection radius of curvature 40 of the second connection segments 38 of the pile shoe 3 correspond to the conicity and second radius of curvature 27 of the second inner segments 25 of the centering sleeve 1 (see, for example, FIGS. 5c and 5d).

The guide section 35 of the pile shoe 3 of this example comprises four guide webs 41 disposed substantially in a cross shape. When the centering sleeve 1 is disposed on the pile shoe 3, outer ends 42 of the guide webs 41 rest against an inner wall 14 of the centering sleeve 1 (see e.g. FIGS. 5b to 5d).

The outer ends 42 of two opposite guide webs 41 of the four guide webs 41 have a widening 43. These widenings 43 have a curvature 44 which is designed to correspond to the inner wall 14 of the centering sleeve 1 for optimum fit.

FIGS. 4a to 4h show different views of another exemplary embodiment of a proposed pile shoe 3. FIG. 4a shows a first side view of the pile shoe 3. FIG. 4b shows a second side view of the pile shoe 3 in a viewing direction that is orthogonal to the viewing direction of the first side view. FIG. 4c shows a bottom view of the pile shoe 3. FIG. 4d shows a top view of the pile shoe 3. FIG. 4e shows a sectional view along the section line E-E shown in FIG. 4a. FIG. 4f shows a sectional view along the section line F-F shown in FIG. 4b. FIG. 4g shows a perspective bottom view of the pile shoe 3. FIG. 4h shows a perspective top view of the pile shoe 3.

The pile shoe 3 shown here corresponds to the pile shoe 3 of FIGS. 3a to 3f with the difference that the ramming ribs 29 of the ramming structure 28 of the pile shoe 3 extend further in the driving direction R and their outer sides 31 are at a larger angle W of about 60° to the pile shoe plate 30. FIGS. 5a to 5f show different views of a pile shoe 3 according to FIGS. 4a to 4h with a centering sleeve 1 disposed thereon according to FIGS. 1a to 1h.

FIG. 5a shows a side view of the pile shoe 3 with centering sleeve 1. FIG. 5b shows a top view of the pile shoe 3 with centering sleeve 1. FIG. 5c shows a first sectional view along the section line G-G shown in FIG. 5a. FIG. 5d shows a second sectional view in a viewing direction that is orthogonal to the viewing direction of the first side view. FIG. 5e shows a perspective bottom view of the pile shoe 3 with centering sleeve 1. FIG. 5f shows a perspective top view of the pile shoe 3 with centering sleeve 1.

The shape of the connection devices 20 of the pile shoe 3 as nose-shaped projections corresponds to the connecting devices 19 of the centering sleeve 1, such that a reliable connection of the pile shoe 3 with the centering sleeve 1 can be established (see, for example, FIGS. 5a and 5c).

Furthermore, for an optimal connection of the pile shoe 3 with the centering sleeve 1, the conicity and first connection radius of curvature 39 of the first connection segments 37 of the pile shoe 3 correspond to the conicity and first radius of curvature 26 of the first inner segments 24 of the centering sleeve 1, and the conicity and second connection radius of curvature 40 of the second connection segments 38 of the pile shoe 3 correspond to the conicity and second radius of curvature 27 of the second inner segments 25 of the centering sleeve 1 (see, for example, FIGS. 5c and 5d).

To ensure a stable fit of the centering sleeve 1 on the pile shoe 3, the outer ends 42 of two opposite guide webs 41 of the guide section 35 of the pile shoe 3 have a widening 43. These widenings 43 have a curvature 44 which is designed to correspond to the inner wall 14 of the centering sleeve 1 (see, for example, FIG. 5b).

FIG. 6 shows a sectional view through a driven pile 2 with a pile shoe 3 with centering sleeve 1 disposed thereon according to FIGS. 5a to 5f.

The driven pile 2 was placed onto the centering sleeve 1 with a driving end 45 of the driven pile 2 facing forward, wherein this placement was facilitated by the centering device 7 of the centering sleeve 1 consisting of flexible plastic. Outer ends of the fin segments 11 of the circumferential fin 9 of the centering device 7 were bent when the driven pile 2 was placed and were thus able to mold to the inner wall 46 of the driven pile 2, wherein a clamping adhesion of the fin segments 11 to the inner wall 46 of the pile results in a positive connection between the centering sleeve 1 and the driven pile 2.

The connection section 18 of the centering sleeve 1 has a first outer surface 21 and an adjoining second outer surface 22 in the direction of the longitudinal axis L, wherein the first outer surface 21 and the second outer surface 22 are substantially conical, wherein the conicity of the first outer surface 21 is greater than the conicity of the second outer surface 22. In other words, the first outer surface 21 slopes more gently towards the longitudinal axis L compared to the second outer surface 22, or the second outer surface 22 slopes more steeply compared to the first outer surface 21 (see FIG. 1a). The first outer surface 21 can be used to facilitate centric placement of the driven pile 2. When a driven pile 2 is placed, the driven pile 2 first hits the first outer surface 21 and when it is placed further in the direction of the longitudinal axis L, the steeper second outer surface 22 results in its adapting well to the inner wall 46 of the driven pile 2. In particular, when using a plastic centering sleeve 1, the driven pile 2 shears off the outer surfaces 21, 22 during placement. This placement and the associated shearing is facilitated by the steeper second outer surface 22. Overall, this can result in a firm and substantially tight connection between the driven pile 2 and the centering sleeve 1, particularly in the area of the second outer surface 22, such that no unwanted contamination (e.g. soil, sand) can penetrate into the interior of the driven pile 2, although it is possible that fluids such as water or gas can still penetrate into the interior of the driven pile 2 (it is therefore possible that the connection is not hermetically sealed).

LIST OF REFERENCE NUMERALS

• • 1 centering sleeve
  • 2 driven pile
  • 3 pile shoe
  • 4 upper end of the centering sleeve
  • 5 lower end of the centering sleeve
  • 6 casing surface
  • 7 centering device
  • 8 outer diameter of the casing surface
  • 9 circumferential fin
  • 10 radial extension of the circumferential fin
  • 11 fin segment
  • 12 recess
  • 13 notch
  • 14 inner wall of the centering sleeve
  • 15 support structure
  • 16 support strut
  • 17 sleeve section
  • 18 connection section
  • 19 connecting device
  • 20 connection device
  • 21 first outer surface
  • 22 second outer surface
  • 23 inner surface
  • 24 first inner segment
  • 25 second inner segment
  • 26 first radius of curvature
  • 27 second radius of curvature
  • 28 ramming structure
  • 29 ramming rib
  • 30 pile shoe plate
  • 31 outer side of the ramming rib
  • 32 contact surface of the pile shoe
  • 33 connection device
  • 34 connection section
  • 35 guide section
  • 36 outer wall
  • 37 first connection segment
  • 38 second connection segment
  • 39 first connection curvature radius
  • 40 second connection curvature radius
  • 41 guide bar
  • 42 outer end of the guide bar
  • 43 widening of the outer end
  • 44 curvature
  • 45 end of the driven pile
  • 46 inner wall of the driven pile
  • L longitudinal axis
  • R driving direction
  • W angle of the outer side of the ramming rib