NL1021143C2 - Method for installing at least one foundation pile in the Method for installing at least one foundation pile in the ground. ground. - Google Patents

Abstract

Method for forming at least one foundation pile or deep wall in the ground, comprising the step of sinking one or more hollow foundation elements (1) into the ground with a substantially vertical orientation. The sinking of the foundation element (1) into the ground takes place during driving of a removable drilling head (3), which drilling head (3), during the sinking of the foundation element (1), extends at least partially below a bottom part of the foundation element (1), by means of excavating members, which can rotate with respect to the foundation element (1) and have radial dimensions which in particular are greater than or equal to external dimensions of the foundation element (1), in which the excavation members, at the same time as the foundation element (1) is being sunk, drills out earth beneath the said bottom part of the foundation element (1), and in which at least the drilling head (3), after the foundation element (1) has been sunk, is removed again from the ground.

Description

Short indication: Method for installing at least one foundation pile in the ground.

The invention relates to a method for forming at least one foundation pile or a deep wall in the soil according to the preamble of claim 1.

Various variants are known from the state of the art to provide such a foundation pile or deep wall. For example, it is known to pile foundation piles or deep-walled elements into the ground with a pile-driving machine, or to vibrate into the soil with a vibrating machine. The deep walls to be fitted will generally be below groundwater level, and must then be substantially groundwater-tight.

A disadvantage here is that the pile-driving or vibrating machines take up a lot of • space and cause noise nuisance during operation. In addition, large forces occur that are transmitted via the soil to at least the nearby environment and can thereby cause damage to, for example, buildings or other existing structures.

One of the newer developments involves turning hollow pipe segments into the ground by means of a rotational movement.

A pipe segment is herein rotated into the ground, after which a following segment is welded to it, and then both segments are further screwed into the ground, etc. Grout bodies must be sprayed between the pipe segments in order to obtain a substantially watertight deep wall.

A disadvantage here is that large forces have to be overcome in order to be able to turn the pipe segments into the ground. In particular, insurmountable problems may arise if large depths have to be overcome. The machine required for this is expensive to manufacture and expensive to use. The provision of the grout bodies between the pipe segments is complex and, depending on the soil composition, relatively unpredictable and unreliable, with the result that groundwater tightness is difficult to guarantee.

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The present invention has for its object to at least partially obviate the above-mentioned disadvantages, or to provide a usable alternative. In particular, the invention has for its object to provide an inexpensive and reliable method for installing a foundation pile or deep wall that requires little space for the machines and can be used at any desired location without thereby causing damage to the nearby environment.

This object is achieved by a method according to claim 1. According to the method, a hollow tube is introduced into the ground substantially vertically. Simultaneously with the introduction into the ground, a removable drill head operates just below the lower part of the hollow tube. The drill bit drills the soil loose which would otherwise have come into contact with the pipe when it was brought to the ground. To this end, the drill head is provided with digging members revolving around a center line of the drill head 15 with radial dimensions which are in particular greater than or equal to the outer dimensions of the tube. The soil can then be conveniently discharged outside the tube. It has been found that the tube can thus be introduced into the ground relatively easily, and that large penetration depths of more than 66 meters can be achieved without the need for a heavy pressing installation, lifting device, vibrating unit or the like. The method can advantageously be applied to work locations where only a small working height is available. The minimum working space height required here is essentially determined by the length of the tubes to be inserted. Advantageously, several pipe segments which can be connected to each other can be used, which together should form one pipe, and which, for example, are welded to each other.

In particular, during bringing to depth, a downward force is exerted on the tube with the aid of a pressing installation. The tube can hereby be pressed evenly into the ground with a relatively light pressing installation without damaging the nearby environment.

The drill bit can advantageously be provided with a flushing section 35 along which a water stream is passed. The soil released can thus be easily removed. Hereby it is possible to drain the water flow with loosely drilled soil up to 3 far outside the direct working location via a suitable pipe system, for example to a sludge depot.

More in particular, the drill bit is arranged such that the digging members can be retracted into a rest position, the largest dimension of the entire drill bit being smaller than the inner dimensions of the tube. After bringing the pipe to depth, the drill bit can then be pulled up through the interior of the hollow pipe. The drill bit is thus not lost and can be reused each time.

At the same time as the drill bit is raised, a curable mass can be injected into the tube. A sturdy, robust foundation pile is thus formed which is surrounded by the tube. It is also possible to remove the drill head and the tubed tube substantially together upwards, while at the same time a curable mass is injected into the tubular cavity left behind. Even then, a reliable, robust foundation pile is advantageously formed. After curing, this only consists of cured injected mass. Not only the drill bit can then be reused, but also the pipe itself.

In another variant, the tube is left in the ground and after removal of the drill bit is at least partially filled with foundation mass. If necessary, the tube can be filled with liquid in an intermediate step, for example a bentonite-containing liquid. This prevents an undesirable filling of the pipe with soil or contaminated groundwater. As the foundation mass, a curable mass can then again be used, but also, for example, a loosely cast foundation mass, such as soil or stones. In the case of partial full casting with bricks, it has been found to be advantageous to provide the pipe wall at least in its lower part with a profiling, such as ridges.

With the above-mentioned method, both loose foundation piles can be formed, as well as deep walls which comprise several piles formed according to the invention.

When the deep walls are used, the tubes can be arranged contiguous to each other, but also while leaving a gap, between which for instance sealing bodies are arranged. The sealing bodies can then be pressed into the ground with the same pressing installation. Drilling has proved to be unnecessary.

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In particular, the tubes are provided on the outside with longitudinally extending connecting pieces. The sealing bodies, such as sheet pile boards, can then be arranged between the connecting pieces. A combination deep wall of hollow pipes and sheet pile boards with reliable properties such as watertightness and strength is thus created. Providing a connecting piece on the outside of the tube is advantageously possible in that the tube is pressed into the ground substantially vertically without having to be rotated about its longitudinal axis. In the case of turning, such a connecting piece would after all provide a large additional resistance. The sheet pile boards can be coupled to the hollow tubes in segments that can be connected to each other.

More in particular, the tubes are herein provided with a profile connecting piece which is adapted to engage by means of a sliding movement in the said longitudinal direction on a profiled edge part of the sealing body.

Further preferred embodiments of the invention are defined in the subclaims.

The invention also relates to a system for applying the method according to one of the claims 19, and to a foundation pile according to claim 20, as well as to a deep wall according to claim 21.

The invention will be further elucidated with reference to the accompanying drawing, in which: Figs. 1-4 schematically show subsequent process steps according to the invention; Fig. 5 is a sectional view along the line V-V in Fig. 4; Fig. 6 is an enlarged view of the details X, Y and Z of Fig. 5; Fig. 7 is a sectional view of an embodiment of a drill bit disposed in a pipe segment; Fig. 8 is a bottom view of Fig. 7 with digging members placed in a drill position; Fig. 9 is a view similar to Fig. 8 with digging members placed in a rest position; Fig. 10 is a schematic sectional view of a system with deployed installation; Fig. 11 is a cross-sectional view of Fig. 10; Fig. 12 is a view similar to Fig. 10 during pipe fitting; Fig. 13 is a view similar to Fig. 10 during the retrieval of the drill bit; Fig. 14 is a view corresponding to Fig. 10 with a plurality of foundation piles formed next to each other; 15a-f show six steps of forming a deep wall with overlapping shaped piles; and Fig. 16 shows a cross-section of a variant of a formed deep wall.

Fig. 1 shows how a hollow tube 1 is positioned in a hydraulic pressing device 2 and is ready to be pressed into the ground. A drill bit 3 is arranged in a lower part of the tube 1. The drill bit has an outer diameter that is smaller than or equal to the inner diameter of the tube 1. During operation, the hydraulic pressing device 2 and the drill bit 3 are driven simultaneously. That is, simultaneously with the advancing tube 1, the drill chuck 3 drills the soil loose which encounters the front part of the tube 1 (FIG. 2). The drill bit 3 is equipped with a flushing part. During drilling, the loosely drilled soil is drained off by means of a water stream that is passed through the flushing section. The water flow is checked in such a way that too much soil is never drained. The water flow with released soil is deposited at a distance from the working location in a sludge depot.

The drill chuck 3 is advantageously provided with a control system whereby any deviations in the penetration direction during the drilling can be corrected.

After the tube 1 (fig. 3) has reached the depth, the drill bit 3 is retrieved upwards by the tube 1. Before the drill bit 3 is retrieved, the tube 1 can be filled with water, so that no inflow of soil can take place from the bottom. After retrieving the drill bit 3, the tubes 1 can be filled with soil, concrete or the like.

Injection tubes are advantageously entrained during pressing into the ground. The injection tubes can serve for the application of lubricant around the tube 1 in order to further reduce the friction. The lubricant may, for example, consist of 6 a bentonite lubrication. The lubrication can also be used to make corrections in the penetration direction of the tube 1.

After a number of tubes 1 have been placed, a sheet pile board 4 is pressed between the tubes 1 (Fig. 4). The same pressing device 2 can be used for this. For the sheet pile boards 4, profiled connecting pieces 6 are welded in advance to the tubes 1 (Fig. 6), into which complementary profiled longitudinal edges 7 of the sheet pile boards 4 can be slid.

After the sheet pile boards 4 have reached depth, the above-mentioned injection tubes can be used to deliver a curable mass, for example a grout mixture. By squeezing such a mass from the underside of the tubes 1, on the one hand, gluing of the tubes 1 to the ground is achieved, and on the other hand the connecting pieces 6 and the longitudinal edges 7 of the sheet pile boards 4 are also provided with an envelope. This enclosure enhances the water-inhibiting function.

In order to be able to further absorb pressure forces on the deep wall, tension anchors can be applied. The tension anchors are advantageously formed by screw injection anchors. The tension anchors can be arranged, for example, from the space inside the hollow tubes 1.

If the tubes 1 have to extend over large depths, and / or if work has to be carried out from a work space with a limited available working height, then it is advantageous to use tube segments that can be connected to each other. Each time a pipe segment is pressed to depth in the ground using the internal bore, a subsequent pipe segment is superimposed on it, for example by welding. The combined press-drilling process can then be continued until this pipe segment has also been brought back to depth. It is advantageous to work alternately on two tubes. At the time of connecting a new pipe segment for one pipe, unused installation parts, such as a drill head drive unit, can be transferred to another pipe and thereby drive the drill head located there. As a result, various components can be used efficiently, and in particular the time required for connecting the pipe segments to each other is optimally utilized.

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The method is particularly suitable for introducing pipes with a relatively large cross-section, in particular larger than one and a half meters. The tube is, for example, constructed from tube segments of approximately two meters.

Prior to pressing the pipe or a first pipe segment thereof into the ground, a housing of approximately one meter is preferably first pressed into the ground. This housing must prevent leaching during the initial part of the drilling-pressing process.

In Fig. 7, a drill head 9 comprises a rotatable digging wheel with adjustable digging teeth 10. Above the digging wheel, a flushing chamber 11 with rubble crusher is provided. The flushing chamber 11 is connected to flushing lines 13. Furthermore, the drill bit 9 comprises a hydraulic drive 12 for rotating the digging wheel during insertion of a pipe segment 14. Along the peripheral wall of the drill bit 9 a coupling system with seal 16 is provided which seals in a sealing manner on the inner peripheral wall of the pipe segment 14. With the aid of control cylinders 17, the drill bit 9 can be accurately aligned with respect to the pipe segment 14 during insertion.

The digging teeth 10 are adjustable between a drill position (Figs. 7 and 8) and a rest position (Fig. 9). In the drilling position, the digging teeth 10 extend beyond the outer peripheral wall of the pipe segment 14. In the rest position, the entire drill head 9 has a cross-sectional dimension that is smaller than the inner peripheral wall 25 of the pipe segment 14.

In Figs. 10 and 11 the drill head 9 with the first pipe segment 14 from Fig. 7 is placed under a pressing installation 20. The pressing installation 20 is anchored to the ground with anchors 21. The installation 20 comprises a hydraulic pressing section 24 which is arranged to to engage the pipe segment 14 and press it down into the ground 22 while driving the digging wheel of the drill bit 9.

FIG. 12 shows a number of further steps in the bored insertion of the tube, wherein a plurality of mutually connected pipe segments 14 have already been pressed into the ground while simultaneously drilling off the ground located below the front part of the first inserted pipe segment 14. It can thus be continued until a desired depth is reached. The pressing section 24 is hereby 8 in an elevated position, so that a new pipe segment can be placed underneath.

FIG. 13 shows a tube which has been brought into depth and into which the drill bit 9 is taken upwards through the interior of the tube. The tube thus inserted can already form a foundation pile. The tube is preferably at least partially filled with foundation mass, in particular curable mass.

FIG. 14 shows the situation in which a plurality of such fully poured foundation piles 26 are formed side by side under the pressing installation 20. It can clearly be seen that the pressing section 24 can be pushed aside along the pressing installation, so that the multiple piles 26 can be formed one after the other without the installation 20.

A deep wall can advantageously be formed by connecting the posts to each other. The connection to each other can take place with the interposition of individual sealing elements as in Figs. 1-6, but can also be achieved by forming the posts next to each other with a small overcutting. Figs. 15a-f show a preferred method for thus forming a deep wall.

First, tubes 30 are placed in the ground at positions 1, 2 and 3 (Fig. 15a). These are then, while simultaneously injecting the released tubular cavity with curable mass 31, again pulled out of the ground together with the used drill bit (Fig. 15b).

Reinforcing bars 32 are provided in the not yet cured mass 31 (Fig. 15c). Subsequently, tubes 34 are placed in the ground at the intermediate positions 4, 5 and 6. During the insertion, the drill bit drills out a small part of the previously formed posts 35 (Fig. 15d). The tubes 34 are then also, while simultaneously injecting the released tubular cavity, with curable mass 36, again pulled out of the ground together with the used drill bit (Fig. 15e). Reinforcing bars 37 are provided in the not yet cured mass 36 (Fig. 15f). A very strong deep wall is thus formed whose piles formed according to the invention connect well and reliably in a watertight manner. The mass 36 can adhere very well to the previously injected mass 31 during the injection, while the reinforcing bars 32, 37 contribute to the rigidity and strength of the deep wall.

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Fig. 16 shows a deep wall, the tubes 40 of which are arranged in a zigzag shape. This shape contributes to a further strengthening of the deep wall and can advantageously be manufactured with the method according to the invention.

In addition to the above-mentioned embodiments, many variants are possible. For example, instead of sheet pile boards, entire bodies of a curable mass, for example a grout mass, can be arranged between the pipes by means of injection. Instead of welding to each other, the pipe segments 10 can also be coupled to each other in other ways. The tubes themselves can also be provided with suitably profiled shaped connecting pieces which are adapted to be slidably accommodated in complementary connecting pieces on already fitted pipes. The drill bit is preferably located at least partially within the lower part of the tube during insertion of a tube. As a result, the drill bit is largely protected against damage from the outside.

Thus, according to the invention, an efficient and reliable method as well as a system for carrying out such a method is provided, which can be applied with great advantage to difficult projects, such as in the vicinity of vulnerable structures, such as a building of historical value, or from limited workspaces, such as from an existing tunnel under the ground, whereby the possibility of working against the prevailing water pressure counts as an advantage.

Claims (18)

Method for forming at least one foundation pile or deep wall in the ground, comprising the step of bringing one or more hollow tubes (1) into the ground, oriented vertically, into the ground, characterized in that bringing the tube (1) to the ground to a depth takes place under the drive of a removable drill head (3), which drill head (3) is at least partially below a lower part of the tube during the bringing of the tube (1) (1) extends with digging members rotatable with respect to the tube (1) which have radial dimensions that are in particular greater than or equal to outside dimensions of the tube (1), wherein the digging members simultaneously with the deepening of the tube ( 1) drill soil below said lower part of the pipe (1), and wherein at least the drill head (3) is removed from the soil after the pipe (1) has been brought to the depth. 20 Method according to claim 1, wherein during bringing the tube (1) into the ground to depth, a downward force is exerted on the tube (1) with the aid of a pressing installation (2). Method according to claim 1 or 2, wherein the drill bit (3) is partially inside the lower part of the tube (1) during the deepening of the pipe (1) in the ground. 4. Method as claimed in any of the foregoing claims, wherein soil released during drilling is discharged by means of a water stream which is passed along a rinsing part (11) of the drill bit (3). Method according to one of claims 1 to 4, wherein the digging members (10), after a depth of the tube (14), are placed from a drilling position into a rest position in which the excavating members (10) have radial dimensions that are smaller than inner dimensions of the tube (14) to be inserted, after which the drill bit (9) is retrieved upwards through the interior of the tube (14). Method according to claim 5, wherein before the drill bit (3) 5 is retrieved upwards, the tube (1) is filled with liquid. 7. Method according to claim 5 or 6, wherein after retrieving the drill bit (9) the tube (14) is at least partially filled with a foundation mass (26). 8. Method as claimed in any of the claims 1-4, wherein after the tube (30) comes to depth, the drill bit and / or the tube (30) are pulled back up again while simultaneously injecting a, in particular curable, , foundation mass (31). 9. Method as claimed in any of the foregoing claims, wherein during introduction into the soil one or more injection pipes are carried along for supplying foundation mass after the pipes have reached depth. 10. Method as claimed in any of the foregoing claims, wherein successively a plurality of tubes (30, 34) are introduced into the ground in a substantially vertical direction next to each other to form the deep wall in the ground. The method of claim 10, wherein the tubes (30, 34) are arranged contiguous. The method of claim 11, wherein the tubes (30, 34) are arranged with a slight overcut. 13. Method as claimed in claim 11, wherein the tubes are pushed into each other substantially in the vertical direction by means of complementary profile connecting pieces extending in longitudinal direction along the outer wall. Method according to claim 10, wherein sealing bodies are arranged between the tubes (1). 15. Method according to claim 14, wherein sheet pile boards (4) are arranged as sealing bodies between the tubes (1). 16. Method as claimed in claim 14 or 15, wherein the sealing bodies and the tubes (1) are pushed into each other by means of longitudinally extending complementary profile connecting pieces (6, 7} substantially in the vertical direction. 17. Method as claimed in any of the foregoing claims, wherein during introduction into the soil one or more injection lines are entrained for supplying lubricant around the tube 15 during pressing into the soil. 18. Method as claimed in any of the foregoing claims, wherein each tube (1) is composed of segments which are connected to each other during pressing into the ground, in particular by means of welding. System for applying the method according to one of claims 1 to 18, comprising: - one or more tubes (1); 25. an installation (2) adapted to forcefully bring the pipes (1) to depth into the ground in the vertical direction in the ground; - a drill head (3) with digging members which have radial dimensions at least during the deepening of the tube into the ground that are in particular greater than or equal to the outside dimensions of the tubes (1) to be inserted; and - a drive unit connectable to the drill bit (3). 12 Foundation pile formed according to the method according to one of claims 1-18. 2 Deep wall comprising a plurality of piles formed next to each other in the ground according to the method according to one of claims 1-18.