Method for forming foundation piles in the ground

Abstract

The present invention relates to a method for forming a foundation pile in the ground, in which a borehole is made in the ground, a pile pipe is gripped by a handling device and inserted into the borehole, a hardenable medium is introduced into the annular space between the wall of the borehole and the outer periphery of the pile pipe, and the medium hardens to form the foundation pile. According to the present invention, it is provided that the hardenable medium is introduced into the borehole via the handling device.

Description

[Technical Field]

[0001] The present invention relates to a method for forming foundation piles in the ground, in particular at the bottom of a body of water, in which, according to the preamble of claim 1, a borehole is made in the ground, a pile pipe is gripped by a handling device and inserted into the borehole, a hardenable medium is introduced into the annular space between the wall of the borehole and the outer periphery of the pile pipe, and the medium hardens to form the foundation pile. [Background technology]

[0002] A method and assembly for manufacturing foundation piles for underwater structures is known from Patent Document 1. In this method, a hole with a support tube is first created in the ground. The created borehole is then filled with a liquid, in particular water. A pile tube, typically a simple steel pipe with a tubular body, is inserted into the resulting borehole. The outer support tube is then withdrawn, and the annular space between the inserted pile tube standing at the bottom of the borehole and the surrounding borehole wall is filled with a hardening medium. Surrounding water may remain inside the pile tube. The load-bearing capacity of the resulting foundation pile is determined by the outer surface of the inserted pile tube relative to the surrounding ground, along with the hardened medium in the surrounding annular space. The water-filled interior can be used, if necessary, to install measuring or testing equipment, for example.

[0003] A device for handling and inserting pile pipes into boreholes is known from US Pat. No. 5,623,999. In this case, the device is configured to be attached to the support cable of a crane. The annular end of the pile pipe can be gripped in a pressure-engagement manner by gripping elements. Overall, the device is configured so that the pile pipe can be pivoted from a horizontal storage position to a vertical installation position.

[0004] Patent Document 3 discloses an assembly and method for producing an underwater foundation using an underwater drilling rig. The underwater drilling rig can be installed at the bottom of a body of water. A foundation borehole is made by using tubular elements. The tubular elements can simultaneously be used to fix the drilling equipment underwater.

[0005] In a known method, after inserting the pile pipe into the prepared borehole, the outer annular space between the side of the pile pipe and the surrounding borehole wall is filled. For this purpose, it is known to insert one or more feed hoses into the annular space, through which a hardening medium, such as a mortar or cement suspension, is introduced into the annular space. In this case, the introduction of the hardening medium should be carried out so that the annular space is filled from the bottom as much as possible, so that liquids, in particular water, located in the annular space are displaced from the bottom to the top by the hardening medium.

[0006] The hose is generally inserted into the annular space manually from outside the borehole. When the borehole depth is 10 meters or more, the feed hose can get stuck in the central area of ​​the borehole, resulting in it not reaching the bottom. This is usually not visible from the outside of the borehole. If the hardening suspension is delivered using such an improperly inserted feed hose, liquid may remain in the annular space below the feed hose and become trapped by the hardening suspension located above it. In such cases, after the suspension hardens, the pile pipe will not be bonded to the surrounding soil along its entire length. As a result, the load-bearing capacity of the associated foundation elements is reduced, and the foundation is no longer secure.

[0007] Foundation elements may need to be reconstructed, which can be extremely time-consuming and costly, and may need to be rebuilt.

[0008] It is further known to provide a feed line for the hardening suspension inside the pile pipe as well. The hardening medium can then be led inside the pile pipe via at least one feed line to the lower region of the pile pipe and introduced into the annular space outside the pile pipe via a corresponding passage. In this case, after the pile pipe is introduced, a corresponding feed for the hardening suspension must be arranged inside the pile pipe up to the passage to the pile pipe or up to the upper joint of the pile pipe. The production of the corresponding joint is time-consuming, labor-intensive and involves the risk of failure. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] European Patent Application Publication No. 2930275A1 [Patent Document 2] International Publication No. 2021 / 180515A1 [Patent Document 3] US Patent Application Publication No. 2010 / 0296875A1 Summary of the Invention [Problem to be solved by the invention]

[0010] The objective underlying the present invention is to identify a method that allows for efficient and reliable production of foundation piles in the ground. [Means for solving the problem]

[0011] This object is achieved by a method having the features of claim 1. Preferred embodiments of the invention are defined in the dependent claims.

[0012] The method according to the invention is characterized in that the hardenable medium is introduced into the borehole via a handling device.

[0013] The basic idea of ​​the invention is to use a handling device not only for gripping and inserting the pile pipe into the borehole, but also for introducing the hardenable medium into the borehole. The handling device is in particular not released from the pile pipe after the pile pipe has been inserted into the borehole, but can remain in a defined initial position on the pile pipe, which position is determined outside the borehole when the pile pipe is gripped by the handling device. This determined relative position between the pile pipe and the handling device allows a reliable delivery of the hardenable medium via the handling device.

[0014] A preferred embodiment of the present invention is that the hardenable medium is introduced into the borehole while the pile pipe is held by the handling device. In this case, the handling device may grip the pile pipe in a storage position, in particular a horizontal position, and therefore may be joined to it, preferably in a pressure-engagement manner. A fixed relative position between the handling device and the gripped pile pipe therefore exists from the start. In this case, a defined relative position between the pile pipe and the handling device can be specified. In this initial position, the hardenable medium can be fed into the pile pipe after the pile pipe has been inserted into the borehole.

[0015] According to a further development of the method according to the invention, the hardening medium is preferably guided by at least one conveying line through the handling device to at least one inlet on the pile pipe, where the hardening medium is preferably guided through the wall of the pile pipe via at least one line and flows out into the annular space via at least one outlet on the outer periphery of the pile pipe. One or more conveying lines for feeding the hardening medium, in particular mortar or cement suspension, from a storage location to the pile pipe, preferably by a pumping device, are arranged on the handling device. The at least one conveying line can be rigidly attached to the handling device or can be attached only after the pile pipe has been gripped. The hardening medium is transferred from the conveying line of the handling device to the pile pipe via at least one inlet, where the medium is guided in the lower region from the inlet to the outer periphery of the pile pipe via one or more lines, which may also be called pile lines. This ensures reliable delivery of the hardening medium to the lower region of the annular space.

[0016] In principle, it is sufficient to provide a single conveying line for the handling device and a single line for feeding the hardenable medium to the pile pipe. According to a further development of the invention, in order to maintain long-term functionality, it is preferable to provide at least two conveying lines and / or lines, which can be switched by at least one valve means to be connected in parallel to form a double feed or to be connected in series for cleaning operations. If at least two lines are provided, a rapid feed of the hardenable medium can be achieved. Furthermore, if two lines are provided, a valve means can be provided that can interconnect the two conveying lines of the handling device and / or the two lines of the pile pipe so that they are connected in series. Thus, feeding can be carried out via the first conveying line or lines, and the draining of the cleaning liquid can be carried out via the second conveying line or lines. As a result, the conveying line or lines can be cleaned and thereby protected from blockage by the hardened medium. Thereby, the handling device with the conveying line and / or the pile pipe with the line can be used not only for one delivery of the hardenable suspension, but also for multiple deliveries.

[0017] According to a preferred variant of the method of the invention, particularly reliable filling of the annular space is achieved by arranging at least one outlet in the lower region of the pile pipe and filling the annular space with the hardenable medium from bottom to top. Preferably, multiple outlets can also be arranged in the lower region of the pile pipe. Outlets can also be arranged in the upper region of the pile pipe as appropriate, and preferably these outlets can be opened by valve means at the start of filling, but only at defined times during the filling process.

[0018] According to a further development of the present invention, the undesired inflow of the hardening medium into the interior of the pile pipe can be prevented or significantly limited by generating an excess pressure at least in the lower part of the pile pipe, which opposes the ingress of the hardening medium from the annular space into the interior of the pile pipe. The excess pressure can, in principle, be generated in any suitable manner. According to an embodiment of the present invention, it is particularly preferred that a partition plate be arranged in the lower part of the pile pipe to create the excess pressure therein, which partition plate seals the lower part from the upper part located above it. The resulting separation of the lower part means that the liquid inside the lower part is sealed therein and can no longer move upward. Therefore, even a slight inflow of the hardening medium from below leads to a pressure increase in the lower part, which opposes further inflow of the hardening medium into the pile pipe.

[0019] In the case of using a pile pipe with a partition plate, a preferred variant of the method is to open at least one through-hole in the partition plate for inserting the pile pipe into a borehole filled with liquid. This allows air or liquid to flow freely upward through the partition plate during insertion without being trapped in the lower part. Only after reaching the end position, especially after the pile pipe is installed at the bottom of the borehole, is the at least one through-hole in the partition plate closed, thereby separating the lower part in a pressure-tight manner. In this state, the partition plate performs the advantageous function described above, i.e., the function of preventing the undesired inflow of hardening medium into the pile pipe.

[0020] Therefore, according to a further modification of the present invention, at least one opening is advantageously closed after the pile pipe is installed at the bottom of the borehole and before the hardening medium is introduced. This measure is particularly effective when the foundation pile is installed at the bottom of a body of water underwater. Therefore, the opening of the partition plate through the opening also allows the pile pipe to be quickly lowered into the water and into the borehole.

[0021] According to an embodiment of the present invention, a further improvement in the manufacture of foundation piles is achieved in that a handling device is connected to a lifting installation for inserting the pile pipe into the borehole, and that after the introduction of the hardening medium the lifting installation is released from the handling device, which remains on the pile pipe as an additional load at least until the medium has hardened.

[0022] In particular, the support cable or rod of a crane can be used as lifting equipment, in which case the handling device is connected to the support cable or rod via a releasable connection means, for example a crane hook.

[0023] After inserting the pile pipe into the borehole and introducing the hardenable medium into the annular space, the lifting equipment can be released from the handling device, but the handling device remains on the pile pipe, so that the handling device can be used as an additional load to fix the pile pipe in place, at least until the hardenable medium has sufficiently hardened and the pile pipe is fixed in place.

[0024] A preferred further development is that after the medium has hardened, the handling device is released from the pile pipe and retrieved. For this purpose, it is possible to use the lifting equipment again with a releasable connection to the support cable or rod to retrieve the handling device. In this case, the handling device can be equipped with an energy-driven or mechanical clamping device, in particular for the pressure-engagement connection to the pile pipe. This connection can be released again to retrieve the handling device.

[0025] The method according to the invention allows the foundation pile to be erected in any desired suitable position in the ground. In particular, the method can be carried out on land, with the pile pipe being inserted into a borehole filled with a liquid, in particular water. In accordance with an embodiment of the invention, it is particularly advantageous for the foundation pile to be erected underwater, at the bottom of a body of water as the ground. The body of water can in particular be a river, a lake, or the sea.

[0026] In particular, underwater boreholes at the bottom of a body of water are more difficult to access than boreholes on land, but the method according to the invention allows reliable construction of foundation piles even at greater water depths.

[0027] In particular, in the case of lakes or rivers, the method can be carried out from the shore using a corresponding device. According to a variant of the embodiment of the invention, it is particularly advantageous if the handling device is operated on the basis of a surface vessel, which may in particular be a boat or a pontoon.

[0028] According to a variant of the embodiment of the method according to the invention, it is further advantageous if the handling device is connected to at least one supply line via a releasable connection means. Via the supply line, also called an umbilical, the delivery of the hardenable medium and the energy supply, in particular electrical, hydraulic and / or pneumatic energy, as well as the data transfer via corresponding data lines, can take place. The supply line can therefore comprise a bundle of different lines and / or hoses.

[0029] The invention is explained in more detail below with reference to preferred exemplary embodiments which are illustrated diagrammatically in the drawings. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is a schematic cross-sectional view of a pile pipe equipped with a bulkhead plate. [Figure 2] FIG. 1 is a schematic view of the lower part of the pile pipe in the borehole. [Figure 3] FIG. 10 is a detailed cross-sectional schematic view of a feeding device on a bulkhead plate of a pile pipe. [Figure 4] FIG. 1 is a perspective view of a handling device for handling pile pipes. DETAILED DESCRIPTION OF THE INVENTION

[0031] According to Fig. 1, a pile pipe 10 is provided which comprises a tubular body 12. A partition plate 20 oriented transversely to the longitudinal axis of the tubular body 12 is arranged in the inner region 13 of the tubular body 12, dividing the inner region 13 into a lower portion 14 and an upper portion 15 which are separated from each other. An annular sealing element 19 may be arranged at the lower edge of the tubular body 12, by means of which the pile pipe 10 may be placed in the bottom of the borehole in a sealing manner as far as possible.

[0032] In the exemplary embodiment shown, the partition plate 20 comprises two through openings 22 (shown diagrammatically), which can be opened or closed as desired by a closing device 24 (also shown diagrammatically). A feeding device 30 comprising two feeding openings 32 (shown diagrammatically), each equipped with an inlet funnel 34, is arranged in the central region of the partition plate 20, as will be explained in more detail below in connection with FIG.

[0033] The feed openings 32 with the inlet funnels 34 are used to feed a hardening medium, in particular a mortar or cement suspension, which can be led via lines 26 below the partition plate 20 to the lower end region of the tubular body 12. In this case, the lines 26 extend through the pipe wall 16 of the body 12 and each lead into an outlet 28 on the outer periphery 17 of the body 12. The hardening medium can thus be led through the inner region 13 of the pile pipe 10 to the lower end region and can flow out of the pile pipe 10 via the outlet 28, as will be explained in more detail below in connection with FIG. 2.

[0034] Figure 2 shows, schematically and not to scale, the lower end region of a pile pipe 10 according to the invention, which is inserted into a borehole 4 in the ground 1. Only the lower region of the borehole 4 is shown, which may have a depth of several meters, typically between 5 m and 30 m. The borehole 4 is filled with a liquid, in particular water or another supporting liquid, for support, so that the borehole 4 does not collapse even in the case of greater borehole depths. Support pipes may also be provided, at least in part.

[0035] The pile pipe 10 with the partition plate 20 can be inserted into the borehole 4 filled with the liquid without any problems if the through-opening 22 on the partition plate 20 is opened by the closing device 24. After the pile pipe 10 reaches its end position, the through-opening 22 can be closed again by the closing device 24, especially when the pile pipe 10 is placed at the bottom 5 of the borehole 4. A hardenable medium can be introduced into the borehole 4 via the line 26, and the hardenable medium can be fed into the inside of the pile pipe 10 in the lower region using the line 26, pass through the pipe wall 16 in the lower end region, and flow out into the annular space 6 via the outlet 28. The annular space 6 is formed between the outer periphery 17 of the tubular body 12 and the substantially cylindrical wall 8 of the borehole 4. In this case, the hardenable medium has a higher density than the liquid in the borehole 4, so that the annular space 6 can be filled from the bottom to the top. In this case, the liquid is displaced upward from the annular space 6 by the hardenable medium.

[0036] The partition plate 20 provided seals the lower portion 14 of the inner region 13 of the pile pipe 10 upward when the through opening 22 is closed. Therefore, the liquid in the lower portion 14 of the pile pipe 10 cannot move upward, and the hardening medium cannot or hardly can penetrate into the inner region 13 of the pile pipe 10. As a result, the inner region 13 can be reliably kept empty, and the hardening medium or suspension can be saved.

[0037] 3 shows in more detail the feeding device 30 of the pile pipe 10 according to FIG. 1. The feeding device 30 may comprise a pot-shaped receptacle 31, which is attached to the central region of the bulkhead plate 20. A feed opening 32 for the line 26 extending downwards is designed in the pot-shaped receptacle 31. For introducing the hardenable medium, the feed opening 32 is provided with an introduction funnel 34 in its upper region. The feed opening 32 can furthermore be designed with a non-return valve 36 (shown only diagrammatically), which in the shown example prevents an unwanted backflow of the hardenable medium from the line 26.

[0038] For delivering the hardenable medium, a handling device 50 according to Fig. 4 can be used according to the invention. The handling device 50 comprises a body 52 with a cover plate 54, on which mounting elements 58 are arranged for placing or positioning the handling device 50 on a top or pile pipe.

[0039] In the exemplary embodiment shown, the handling device 50 can be releasably attached to the inside of the pile pipe 10 via a gripping device 56 using at least one clamp or gripping element 57, which can alternatively or additionally be configured as a pressure-engagement clamping device. Preferably, a plurality of gripping elements 57 are arranged around the circumference of the generally tubular or barrel-shaped body portion 52.

[0040] The pile pipe 10 can be picked up from the pile pipe storage by the handling device 50 already on the ground surface or on a surface vessel. The pile pipe can be in any position when picked up, for example, horizontally or vertically. The handling device can be connected to a lifting installation, in particular a crane, via a holding element 55 in the upper end region of the body 52. ​​The pile pipe 10 can thus be inserted from its storage position into the borehole 4 in the ground 1 using the handling device 50.

[0041] Furthermore, the handling device 50 is provided with a feeding device 60 (shown only diagrammatically) which, in the exemplary embodiment shown, comprises a conveying line 64 extending from an inlet device 62 at the upper end of the body part 52 to an outlet device 66 at the lower part. The outlet device 66 is configured to engage with the pile pipe 10 for feeding the hardenable medium via the inlet funnel 34 of the feeding device 30, according to Fig. 3. Furthermore, a corresponding coupling unit can be provided on the handling device 50 for interacting with the coupling element 23 on the feeding device 30 of the pile pipe 10 to ensure accurate positioning and positional stability.

[0042] Via supply line 80, which may also be referred to as an umbilical, hardenable medium, energy and / or data can be fed through releasable joint device 70, where the hardenable medium is transferred to inlet device 62 in the upper end region of body portion 52. Separate supply lines can be provided, or separate lines can be provided.

[0043] After the annular space 6 has been filled with the hardenable medium, the joining line 80 and / or the lifting equipment can be released from the holding element 55, whereupon the handling device 50 can remain on the pile pipe 10 as an additional load, at least until the hardenable medium for forming the foundation element of the soil 1 has hardened. Thereafter, the handling device 50 can be released again from the pile pipe 10 and retrieved.

Claims

1. A method for forming foundation piles in the ground, comprising: - a borehole is made in the ground; - the pile pipe is gripped by a handling device and inserted into the borehole; - a hardening medium is introduced into the annular space between the wall of the borehole and the outer periphery of the pile pipe, said medium hardening to form the foundation pile; - the hardenable medium is introduced into the borehole via the handling device.

2. A method as described in claim 1, wherein the hardening medium is introduced into the borehole while the pile pipe is held by the handling device.

3. 2. The method according to claim 1, wherein the hardening medium is guided by at least one conveying line through the handling device to at least one inlet of the pile pipe, the hardening medium is guided through the pipe wall of the pile pipe via at least one line, and is discharged into the annular space through at least one outlet on the outer periphery of the pile pipe.

4. 4. The method according to claim 3, wherein two conveying lines and / or lines are provided, said two conveying lines and / or lines being switched by at least one valve means to be joined in parallel to form a double feed line or to be joined in series for cleaning operations.

5. The method of claim 3 , wherein at least one outlet is located in a lower region of the pile pipe, and the hardenable medium fills the annular space from bottom to top.

6. 2. The method of claim 1, wherein an overpressure is generated at least in the lower part of the pile pipe, the overpressure opposing the ingress of the hardenable medium from the annular space into the interior of the pile pipe.

7. 7. The method of claim 6, wherein a bulkhead plate is disposed in the lower portion of the pile pipe to create an overpressure therein, the bulkhead plate sealing the lower portion from an upper portion located above it.

8. 8. The method of claim 7, wherein at least one through opening on the bulkhead plate is opened for inserting the pile pipe into a borehole filled with liquid.

9. 8. The method of claim 7, wherein the at least one through opening is closed after the pile pipe is installed at the bottom of the borehole and before the hardenable medium is introduced.

10. the handling device is connected to a lifting facility for inserting the pile pipe into the borehole; 2. The method of claim 1, wherein after the introduction of the hardenable medium, the lifting equipment is released from the handling device, which remains on the pile pipe as an additional load at least until the medium has hardened.

11. The method of claim 10 , wherein after the hardening of the media, the handling device is released from the pile pipe and retrieved.

12. The method of claim 1 , wherein the foundation piles are created underwater at the bottom of a body of water as a foundation.

13. The method of claim 1 , wherein the handling device is operated based on a surface vessel.

14. 10. The method of claim 1, wherein the handling device is connected to at least one supply line via a releasable connection device.

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