Method and set of piling tools for creating a pile in the ground

Abstract

 Method and a set of piling tools to create a pile into the ground. In the method a hollow foundation casing (30) is introduced into the ground by a pile driving device (50). In a later step the hollow foundation casing (30) is withdrawn from the ground to obtain a hole. The remaining hole in the ground is filled with setting substance to obtain a pile. The withdrawal of the foundation casing (30) is done by a dedicated hoisting device (40) which is positioned at ground level adjacent the foundation casing.

Description

[0001] A first aspect of the present invention relates to a method and a set of piling tools to create a pile into the ground. In the method a hollow foundation casing is introduced into the ground by a pile driving device. In a later step the hollow foundation casing is withdrawn from the ground to obtain a hole. The remaining hole in the ground is filled with setting substance to obtain a pile.

[0002] Hollow foundation casings are used in several methods for pile driving. From EP1857597 in the name of the same applicant, a method is known for inserting foundation casings into the ground. In a first step at least two telescopically connected pipe segments which form the hollow foundation casing are positioned above a base plate. Subsequently the pipe segments are driven into the ground by ramming at least one of the pipe segments and the base plate by a pile-driving ram. Owing to the fact that the pile-driving ram passes through the hollow foundation casings, the vibrations and noise nuisance above the ground remain limited. Herewith, the application of hollow foundation casings is in particular advantageous for pile driving in the close neighbourhood of buildings. The reduction of vibrations reduces the risk on cracks in a wall of the building. Another advantage brings the application of the telescopically connected pipe segments. No labour-intensive actions, such as welding or screwing down, are necessary on the site of the pile driving operations. In addition the set of telescopic pipe segments is compact, such that it advantageously can be used in small working spaces.

[0003] EP1857597 discloses a particular embodiment of the method, wherein a withdrawal element is used to withdraw the foundation casing. The withdrawal element is fed into the hollow foundation casing and comprises a connecting element to provide a connection of the withdrawal element to an inner side of a pipe segment. After establishing the connection, the pipe segments are withdrawn from the ground. The withdrawal element is withdrawn by a hoisting cable which is guided by a derrick to a derrick winch. A drawback of this method step is that during the withdrawal of the foundation casing large forces may act on the derrick which require a heavy and strong design of the derrick. The heavy derrick may cause problems in handling at limited working areas.

[0004] The object of the present invention is to at least partially overcome at least one of the abovementioned disadvantages, or to provide a useful alternative. In particular, the object of the invention is to provide an improved pile driving method for limited working spaces and an improved set of piling tools for use in the pile driving method.

[0005] This object is achieved by a method for creating a pile in the ground according to claim 1.

[0006] The method for creating a pile in the ground comprises several steps.

[0007] In a first step a set of piling tools is provided. The set of piling tools comprises a hollow foundation casing, a pile driving device and a dedicated hoisting device.

[0008] The foundation casing comprises at least one pipe segment. The foundation casing is provided with a ramming surface to lower the foundation casing into the ground. Preferably the ramming surface is provided inside the hollow foundation casing.

[0009] The pile driving device is arranged for introducing the foundation casing into the ground. The pile driving device comprises a derrick and a derrick winch. The derrick is a longitudinally mast which is shaped to reach above a proximal end of the foundation casing. Preferably, the pile driving device further comprises a pile-driving ram which is insertable into the hollow foundation casing to ram onto the ramming surface of the foundation casing.

[0010] The hoisting device is arranged for withdrawing the hollow foundation casing out of the ground. The hoisting device comprises at least one hoisting winch to wind at least one hoisting cable. The hoisting winch is arranged on a framework. A free end of the hoisting cable is connectable to the at least one pipe segment.

[0011] In a step of the method the hollow foundation casing is positioned in an up right position at a working space. The derrick of the pile driving device may be used to lift the foundation casing in up right position.

[0012] In a step of the method, the framework of the hoisting device is positioned adjacent the foundation casing. The hoisting device is preferably positioned at a lower region of the pile driving device.

[0013] In a step of the method the at least one free end of the at least one hoisting cable is connected to an outer surface of the pipe segment at the distal end of the foundation casing. Instead of introducing the hoisting cable through the hollow foundation casing and fasten the hoisting cable at an inner surface, the hoisting cable is fastened to the outside of the pipe segment.

[0014] In a step of the method, the pile driving ram is introduced into the foundation casing. The pile driving operation starts when ramming the pile-driving ram against the ramming surface of the foundation casing to lower the foundation casing into the ground. The derrick is used to operate the pile driving ram.

[0015] In a step of the method according to the invention the at least one pipe segment is withdrawn out of the ground by using the dedicated hoisting device. The at least one hoisting winch on the framework is driven to rewind the hoisting cable to pull back the pipe segment. The framework is preferably positioned at a lower region of the derrick of the pile driving device at ground level. The framework is preferably ground supported. Advantageously, during withdrawing of the foundation casing, forces acting on the framework are supported to the ground.

[0016] The method according to the invention uses a dedicated hoisting device which is dedicated for withdrawing the foundation casing. The pile driving device is dedicated to be used for introducing the foundation casing into the ground. In the method according to the invention, the derrick of the pile driving device is not used to withdraw the foundation casing when high pulling forces are required to withdraw the foundation casing. In stead of the derrick, the dedicated hoisting device is used to withdraw the foundation casing when high pulling forces are required. This provides the advantage that the derrick of the pile driving device may have a relatively light construction. The derrick of the pile driving device may especially be constructed to withstand acting forces during positioning and ramming of the foundation casing. In other words, the derrick of the pile driving device may be designed to meet the requirements to position a foundation casing and to lift and lower the pile driving ram. The separate hoisting device is especially designed to withstand occurring forces which are in comparison with the ramming and positioning forces relatively high during the step of withdrawing the foundation casing. Withdrawing the foundation casing may require in some cases forces of e.g. about 50tons, while forces during ramming may be about 5tons.

[0017] The used hoisting device has preferably a compact configuration. In particular, the hoisting device has maximum outer dimensions of at most 1 meter in height and at most 2 meters, in particular at most 1 meter in width and length. According to the invention no extending heavy derrick to the proximal end of the foundation casing to introduce the hoisting cable in an interior of the foundation casing is necessary for withdrawing activities, because the at least one hoisting cable is connected to the outside of the pipe segment. The arrangement of an extending longitudinal derrick for withdrawing purposes would be disadvantageous, because such a derrick would require a lot of steelwork to strengthen the derrick against bending stresses originating from high withdrawal forces.

[0018] The advantage of the use of a compact hoisting device which is dedicated to the withdrawing step is that the components of the set of piling tools may get more practical and manageable. The hoisting device can easily be positioned at a base of the piling device. The pile driving device may have a light construction and the hoisting device may have a compact configuration, which makes the set of piling tools easy manageable.

[0019] In particular, the method according to the invention is suitable to be applied in a limited working space. The working space may for example be limited by adjacent buildings, fences or other objects. The method according to the invention is for that reason in particular favourable in combination with the use of at least two telescopically connected pipe segments. Telescopically connected pipe segments are in particular used in limited working spaces. The foundation casing may comprise an assembly of individual pipe segments which individual pipe segments are slidably insertable into each other. The set of piling tools can be transported as separate components to the limited working space and build up on site. The relatively light components of the piling tools can be easily transported by common available transporting means.

[0020] In an embodiment of the method according to the invention a vehicle may be used, wherein the set of piling tools is arranged on the vehicle. The set of piling tools may at least partially be operatable from an operating unit of the vehicle.

[0021] In an embodiment of the method according to the invention, the used hoisting device comprises at least two hoisting winches including respectively at least two hoisting cables. The hoisting winches may be positioned opposite each other adjacent the foundation casing. In other words, the foundation casing may be arranged in between the at least two hoisting winches. Free ends of the at least two hoisting cables may be connected to the outer circumference of the pipe segment. When the foundation casing is withdrawn, the at least two hoisting cables are tensioned and rewinded by the hoisting winches. The advantage of using at least two hoisting cables is that a resulting total pull back force can be generated which extends about an axial axis of the foundation casing. Slanting of the foundation casing during the step of withdrawal may be prevented.

[0022] Preferably the foundation casing further comprises a releasable base plate, which base plate provides a ramming surface and forms a closed distal end of the hollow foundation casing. Herewith, the ramming forces act on the base plate which allows a light weighted design of the pipe segment.

[0023] In a further embodiment of the method according to the invention, the pile-driving ram is moved down and in the first instance rams the base plate, in such a way that the base plate drops a certain distance, after which in the second instance the pile-driving ram rams the pipe segment, in such a way that the pipe segment drops. The initially connected hoisting cables may be sufficient flexible to withstand the ramming of the pile driving ram. Advantageously, the pipe segment may have a further light weighted design which makes the use of the set of piling tools more suitable to be applied in a limited working space.

[0024] In an embodiment of the method according to the invention, the method comprises the following steps: positioning a base plate and a hollow foundation casing in particular formed by at least two telescopically connected pipe segments; moving a pile-driving ram up with a pile-driving device; moving the pile-driving ram down through the foundation casing; letting the pile-driving ram the base plate and the foundation casing; withdrawing the foundation casing from the ground using a hoisting device, so that a hole is left in the ground; leaving the base plate behind in the hole that is left; and introducing a setting substance on top of the base plate in the hole that is left. Preferably, in a step of the method a reinforcement member is provided in the hole that is left.

[0025] In a particular embodiment of the method according to the invention a vehicle is used which comprises at least partially or preferably all components of the set of piling tools for carrying out the method, wherein the set of piling tools is at least partially operatable from an operating unit. The vehicle may have an operator seat provided with the operating unit. The vehicle may be provided with a pile driving device. The vehicle may comprise at a front region a derrick for positioning and introducing a foundation casing. The derrick may be rotatable mounted to the vehicle about a horizontal axis to bring the derrick from a transport in a standing working position. The derrick may have a derrick cable which may be winded by a derrick winch. The derrick winch may be installed on board of the vehicle, in which the derrick cable extends from the derrick winch over the derrick. The derrick may comprise a guidance for linearly guiding a foundation casing which includes at least one pipe segment. The foundation casing may comprise at least two telescopically connected pipe segments to obtain relatively long piles. The vehicle may have a hoisting device at a lower front region. The hoisting device may comprise a framework, in particular a platform, wherein at least one hoisting which is mounted to the framework.

[0026] Further the invention relates to a set of pile driving tools as defined in claim 7.

[0027] The set of piling tools is in particular suitable to carry out the method to create a pile in the ground according to the invention. The set of piling tools can be used as a set of separate components to build on site a piling installation. Alternatively, the set of piling tools can be assembled as a piling installation, e.g. assembled to a vehicle. The set of piling tools comprises a hollow foundation casing, a pile driving device and a dedicated hoisting device.

[0028] The hollow foundation casing comprises at least one pipe segment and preferably a releasable base plate. The foundation casing preferably has a ramming surface to lower the foundation casing into the ground by ramming. The ramming surface is preferably arranged inside the hollow foundation casing. The base plate may form a closed distal end of the foundation casing during the introduction of the foundation casing into the ground.

[0029] The pile driving device for introducing the foundation casing into the ground comprises a derrick, a derrick winch, a derrick cable and a pile-driving ram. The derrick is arranged to reach above a foundation casing and the derrick winch is arranged to lift and lower the pile-driving ram. The derrick may have a derrick guidance to guide the foundation casting. The pile-driving ram is preferably movable inside the hollow foundation casing to ram onto a ramming surface of the foundation casing. Preferably, the ramming surface is provided at the distal end of the foundation casing to reduce vibrations and disturbances to the environment. Preferably, the ramming surface is provided at the base plate to prevent damages to the pipe segment.

[0030] According to the invention, the pile driving device is separately provided from the hoisting device. The hoisting device for withdrawing the hollow foundation casing out of the ground comprises at least one hoisting cable which is at one end connectable to an outer surface of the at least one pipe segment and at the other end winded round a drivable hoisting winch. Preferably, the hoisting winch is drivable by a hydraulic motor to exert large forces. The hoisting winch is arranged on a framework. The framework is ground based. The framework may have ground supporting means like stamps or a flat underside to install the framework on the ground. In a piling method, the framework can be placed on the ground close to the foundation casing. Preferably, the framework is box shaped with outer dimensions of at most 1 meter in height and at most 2 meters, in particular at most 1 meter in width and length. The framework has a compact configuration to provide a short path for the hoisting cable from the hoisting winch to the distal end of the foundation casing. Occurring forces during a withdrawal of a foundation casing are leaded directly over the short path to the ground by the hoisting device. The framework may have a height of e.g. at most one meter to limit the short path. The framework is free from a longitudinal withdrawal derrick as guidance for a hoisting cable which derrick is susceptible for bending and failure. A hoisting cable may extend directly from the hoisting winch into the ground towards a distal end of a foundation casing. Advantageously, the compact ground based configuration of the framework enables a strong and light construction of the hoisting device. Large occurring forces during hoisting of the hoisting cables to withdraw the foundation casing from the ground can be overcome by the strong framework and direct support from the ground, while at the other side the framework remains light weighted for handling purposes.

[0031] In an embodiment the set of piling tools according to the invention, the framework of the hoisting device is a platform. The platform may be arranged by welded steel profiles. The platform can be positioned adjacent an up right positioned foundation casing. The platform may define a mounting surface which is in parallel with a ground surface. The hoisting winch may be mounted on the mounting surface of the platform, wherein a free end of a winded hoisting cable may be guided along the platform to extend towards a distal end of a foundation casing.

[0032] In an embodiment of the set of piling tools according to the invention, the framework of the hoisting device may include a passageway to allow the foundation casing to pass through the framework into the ground. At least one hoisting winch is positioned adjacent the passageway. Preferably at least two hoisting winches are positioned opposite each other adjacent the passageway. Advantageously, the at least two hoisting winches at opposite sides of the passageway may prevent the framework from asymmetrical loads and from moving aside during withdrawing of the foundation casing.

[0033] In an embodiment of the set of piling tools according to the invention, the framework of the hoisting device has a window frame shape. The open area of the window frame may serve as a passageway. Advantageously, the framework may be positioned directly and stable onto the ground. The window frame shape is strong to withstand occurring forces during withdrawal activities. The occurring forces are efficiently distributed over the window frame shaped framework. Additionally, the window frame shape provides a relative light weight construction which is practical in limited working spaces.

[0034] Further, the invention relates to a vehicle provided with the set of piling tools according to the invention. In an embodiment of the set of piling tools according to the invention, the set of piling tools are arranged on a vehicle. The vehicle may be provided with a pile driving device. The vehicle may comprise at a front region a derrick for positioning and introducing a foundation casing. The derrick may be rotatable mounted to the vehicle about a horizontal axis to bring the derrick from a transport in a standing working position. The derrick may have a derrick cable which may be winded by a derrick winch. The derrick winch may be installed on board of the vehicle, in which the derrick cable extends from the derrick winch over the derrick. The derrick may comprise a guidance for linearly guiding a foundation casing which includes at least one pipe segment. The foundation casing may comprise at least two telescopically connected pipe segments to obtain relatively long piles. The vehicle may have a hoisting device at a lower front region. The hoisting device may comprise a framework, in particular a platform, wherein at least one hoisting which is mounted to the framework.

[0035] Further preferred embodiments are described in the remaining claims.

[0036] The invention will be explained in more detail with reference to the appended drawings. The drawings show a practical embodiment according to the invention, which may not be interpreted as limiting the scope of the invention. Specific features may also be considered apart from the shown embodiment and may be taken into account in a broader context as a delimiting feature, not only for the shown embodiment but as a common feature for all embodiments falling within the scope of the appended claims, in which:

Fig. 1a shows in a schematic view a pile driving vehicle provided with a set of piling tools according to the invention;

Fig. 1 b shows in a schematic front view a hoisting device according to the invention;

Fig. 2 shows in a schematic view a pile driving vehicle with a set of piling tools according to the invention; and

Fig. 3 shows in a cross sectional view at a distal end of a hollow foundation casing several embodiments of a base plate and a sealing element according to the invention.

[0037] In the appended drawings equal reference numbers are used for corresponding components.

[0038] Fig. 1a shows in a schematic view a vehicle 2 which is provided with a set of piling tools. The vehicle is shown in a starting position to carry out a piling method. The vehicle 2 is provided with a pile driving device 50. The vehicle has at a front region a derrick 51 for positioning and introducing a foundation casing. The derrick 51 is rotatable mounted to the vehicle 2 about a horizontal axis 55 to bring the derrick 51 from a transport in a standing working position. A derrick cable 52 extends about the derrick 51 to a pile drive ram and is windable by a derrick winch (53 not shown) on board of the vehicle. The derrick 51 further comprises a guidance 54 for linearly guiding a foundation casing 30. The foundation casing 30 comprises an outer pipe segment 3.3 and an inner pipe segment 3.1.

[0039] The vehicle 2 has further a hoisting device 40 which is provided at a lower front region of the vehicle 2. The hoisting device 40 is connected to the pile driving device 50. The hoisting device 40 is in the working position arranged at ground level at the base of the pile driving device 50. The hoisting device 40 is rotatable together with the pile driving device 50 and can be lowered to the ground. During use, the hoisting device 40 normally rests on the ground during a piling method such that withdrawal forces are transferred to the ground.

[0040] The hoisting device 40 comprises a framework 41, or a so called platform, wherein at least one hoisting winch 42 is mounted at the framework 41. In this case two hoisting winches 42 are provided at two opposite sides of the foundation casing 30. One of the winches 42 is shown. The foundation casing 30 extends from above through the framework 41 through a passageway. A hoisting cable 43 is winded round the hoisting winch 42 and connected at its free end to a distal end of the foundation casing 30.

[0041] Fig. 1 b shows in a schematic front view a hoisting device according to the invention. The hoisting device has a framework 41. The framework is window frame shaped. The framework has a simple and compact configuration. The framework is made by assembling steel profiles which are arranged in a common plane. Herewith, the framework forms a platform. The platform has a top surface for mounting at least one hoisting winch and a bottom surface to rest on the ground.

[0042] A passageway 44 is provided in the centre of the framework. The passageway is indicated by a center line. A foundation casing may pass through the passageway 44 during a piling operation. A hoisting winch is provided at both sides of the passageway. A first hoisting winch 421 and a second hoisting winch 422 is mounted on top of the framework.

[0043] Fig. 2 shows in a schematic view a vehicle 2 comprising a set of piling tools according to the invention in a working position. The vehicle, in particular a hoisting crane, is used to bring the set of piling tools 1 into position. The set of piling tools is used to create a pile in the ground. The set of piling tools comprises a hollow foundation casing 30. The foundation casing 30 comprises at least one pipe segment. In this case three pipe segments are telescopically connected to each other. The pipe segments have a decreasing diameter and are slidably connected. Fig. 1 shows the foundation casing in a collapsed configuration. Fig. 2 shows the foundation casing in an extended configuration. The inner pipe segment 3.1 is moved away from the pipe segment 3.3. The outer pipe segment 3.3 is moved partially into the ground.

[0044] A hoisting cable 43 is connected to a distal end of the foundation casing. The hoisting cable 43 is connected by a connecting element to the most inner positioned pipe segment. The hoisting cable 43 is at the proximal end connected to at least one hoisting winch 42. The hoisting winch 42 is arranged on a table shaped frame work 41 having a platform and stamps to the ground. A passageway is provided in the framework to transfer and guide the foundation casing 30 through the framework.

[0045] The set of piling tools further comprise a base plate 10. The base plate is positioned at the distal end of the foundation casing 30. The foundation casing can be driven into the ground by using a pile-driving ram. The pile driving ram moves through the hollow foundation casing 30 and rams on the base plate 10 and subsequently or simultaneously on the at least one of the pipe segments of the foundation casing 30.

[0046] Fig. 3 shows in a cross sectional view a distal end 31 of a hollow foundation casing 30. The distal end 31 is axially aligned with a base plate 10. The base plate 10 has a plate shaped bottom part 11 with a substantially flat underside. The base plate 10 is provided with an external collar wall at an upper side of the bottom part. The external collar wall is welded to the bottom part. The external collar wall 12 has an inner collar surface and an outer collar surface, wherein a sealing element 20 is positioned adjacent the inner collar surface. The sealing element is made of a flexible material like silicon or rubber. The elastic properties of the sealing element provide a sufficient watertight connection between the base plate 10 and the distal end of the foundation casing 31.

[0047] Fig. 3 further shows a connection of a hoisting cable 43 to the foundation casing 30. The hoisting cables 43 are positioned at an outer surface of the foundation casing 30. The hoisting cables 43 are easily connected by an eye-connection to an outer wall part on the distal end 31 of the foundation casing 30. The foundation casing 30 has at the distal end 31 a thickened portion which provides a re-inforced part which is suitable for the connection of the hoisting cable. During the use of the pile-driving ram, the hoisting cable 43 is untensioned. During the step of withdrawal of the foundation casing, the hoisting cables 43 are tensioned by hoisting winches which are arranged at ground level.

[0048] Besides the embodiments shown in the figures, many variants are possible, but remaining within the scope of protection of the invention as defined in the appended claims.

[0049] For instance, as an alternative variant for a hoisting device, a U-shaped framework may be arranged to position two winches at two sides of a foundation casing. Alternatively, four winches may be arranged around a passageway in a framework of a hoisting device.

[0050] Thus, according to the first aspect of the invention a set of piling tools is provided which may improve a pile driving method. The set of piling tools is improved in that it comprises relatively light weighted components. The set of piling tools is for that reason more practical in use. In particular when carrying out piling methods which have to be performed in limited working spaces.

[0051] A second aspect of the present invention relates to a method and set of piling tools for carrying out the method according to the preamble of clause 1.The set of piling tools comprises a telescopic foundation casing.

[0052] Such a telescopic foundation casing is known from the prior art. The telescopic foundation casing comprises at least two pipe segments which are telescopically connectable. The at least two pipe segments have different outer dimensions to slide the pipe segments into each other. The at least two pipe segments are hollow and have an open proximal end for introducing a pile driving ram into the foundation casing. A distal end of the foundation casing may be open to let the pile driving ram pass through the foundation casing to hit onto a base plate.

[0053] In a known piling method, the telescopic foundation casing is used to create a pile in the ground. In a first step the foundation casing is positioned in upright position at a working space. The at least two pipe segments of the foundation casing are then in a collapsed configuration. In the collapsed configuration, the at least two pipe segments are slided over each other. During a ramming step, the pipe segments of the foundation casing slide out of each other to an extended configuration. The foundation casing has a maximum extension and a corresponding maximum length, in which the pipe segments are maximally slided out of each other.

[0054] Due to geographic soil differences, the telescopic foundation casing is used with different lengths. Generally, explorer activities with a probe are performed to determine a necessary depth for the pile and corresponding length of the foundation pile. Subsequently, a corresponding telescopic foundation casing is selected. However, the maximum length of the foundation casing is not always necessary to reach a predefined depth.

[0055] A first drawback of the known telescopic foundation casing is that it is often unclear during piling how far the telescopic foundation casing has been lowered into the ground before reaching the maximum length. Sometimes pipe segments get jammed before reaching the predefined depth. A most outer positioned pipe segment which still stands at ground level may not provide a satisfying indication of how far the foundation casing has been lowered.

[0056] When it appears that the maximum length appears is not necessary during piling, it may be a further drawback that the remaining outer pipe segment extends far above ground level. That may be a problem to perform subsequent steps of the piling method. It may e.g. be difficult to fill the foundation casing with a setting substance, when the proximal end of the foundation casing extends two meters above ground level.

[0057] It is an object of the present invention to at least partially eliminate the above mentioned drawbacks and/or to provide a useable alternative. In particular, it is an object of the invention to provide a set of pilling tools for carrying out a piling method, in which a telescopic foundation casing is lowered into the ground.

[0058] According to the invention, this object is achieved by a method according to clause 1.

[0059] According to the invention a method is provided for creating a pile in the ground. The method comprises a step of providing a set of piling tools. The set of piling tools comprises a hollow foundation casing including at least an inner and an outer pipe segment which are telescopically connected to each other. The foundation casing is extendable from a collapsed configuration to an extended configuration by moving the inner pipe segment at least partially out of the outer pipe segment.

[0060] The method further comprises a step of positioning the foundation casing in upright position. The foundation casing has a length direction which defines an axial direction. The foundation casing is normally positioned substantially vertical to obtain a pile which is suitable to carry vertical loads.

[0061] The method further comprises a step of introducing a pile driving ram into the hollow foundation casing. The foundation casing has an interior. The foundation casing is open at a proximal end to receive the pile driving ram.

[0062] The method further comprises a step of ramming onto the inner pipe segment to lower the foundation casing into the ground. The inner pipe segment may comprise a base plate, wherein the pile driving rams onto the base plate.

[0063] The method according to the invention is improved in that the provided set of piling tools further comprises a longitudinal extension determination member. Preferably, the extension determination member is bendable. The extension determination member comprises e.g. a cable or a chain. The method further comprises the step of connecting one end of the extension determination member to a pipe segment, in particular to a distal end of the inner pipe segment. The method further comprises a step of introducing the extension determination member together with the foundation casing into the ground, wherein an opposite end of the extension determination member is kept above ground level. The extension determination member extends preferably at an outer surface along the foundation casing. Further, the method comprises a step of determining an extension of the foundation casing by determining a corresponding length of the extension determination member.

[0064] The use of the extension determination member enables an operator of the method to determine a reached depth of a lowered foundation casing. The corresponding length of the extension determination member may be an in the ground introduced length of the extension determination member. An introduced length of the extension determination member may be measured to determine an amount of extension of the foundation casing. The extension determination member may have at least one marking to determine an introduced length. Taking into account a total length of the extension determination member, the operator may determine a length of the extension determination member measured from the opposite end to an intermediate position of the extension determination member at ground level to determine an achieved extension of the foundation casing. The operator herewith has obtained valuable information about the extension of the foundation casing already during the lowering of the foundation casing. Problems during the lowering e.g. a jammed foundation casing may quickly be detected during ramming. The operator can take measures to warrant that a predefined depth for creating a pile will be reached.

[0065] In an embodiment of the method according to the invention the opposite end of the extension determination member is connected to the foundation casing. By connecting the opposite end of the extension determination member a predefined length of the extension determination member is obtained. The predefined length corresponds with a predefined extension of the foundation casing. An operator may have obtained a predefined extension by taking ground measurements. A desired depth for a pile may be used to determine the extension of the foundation casing.

[0066] A first advantage may be that an available foundation casing with a maximum extension creating long piles is now also available to be used for shorter piles. The extension determination member may be used to block the extension of the foundation casing before the maximum extension is reached. Herewith, the available foundation casing can be used for a plurality of desired depths.

[0067] Preferably, the opposite end of the extension determination member is connected to the proximal end of the foundation casing. Herewith, a further advantage may be achieved in that the extension of the foundation casing can be such to obtain a lowering of the foundation casing wherein the proximal end of the foundation casing is sufficient lowered into the ground to obtain a proper working position to carry out subsequent steps of the method. It may e.g. be possible to lower the proximal end of the foundation casing until about 30cm above ground level which provides a good working height to fill the foundation casing with setting substance during withdrawal of the foundation casing.

[0068] In an embodiment of the method according to the invention, the opposite end of the extension determination member is winded round an extension winch, such that the extension determination member extends along the foundation casing. During lowering of the foundation casing the extension determination member may be unwinded from the extension winch. Advantageously, the extension determination member is properly introduced along the foundation casing into the ground. Loops may be prevented which may cause blockages. During withdrawing of the foundation casing the extension winch may prevent damages to an obtained hole in the ground. The extension winch may keep the extension determination member substantially straight along the foundation casing and may prevent loops in the extension determination member. Loops in the extension determination member during the step of withdrawing may cause blockages in the hole or damages of a hole wall. The hole may cave in during withdrawing of the foundation casing. For that reason it is advantageous, to prevent loops in the extension determination member by using the extension winch.

[0069] In a further embodiment of the method according to the invention, the extension determination member is connected at an intermediate position to the foundation casing. The opposite end of the extension determination member may be connected to the foundation casing via the extension winch and branched at the intermediate position of the extension determination member to connect the extension determination member directly to the foundation casing. The extension determination member may have a branched portion to connect the extension determination member to the foundation casing. Preferably, the branched portion is at one end connected to the foundation casing at the proximal end of the foundation casing. The branched portion may have a length which corresponds to a maximum extension of the inner pipe segment from a collapsed configuration of the foundation casing.

[0070] The extension determination member may comprise a first cable including an end which is connected to the distal end of the foundation casing and a opposite end which is winded round an extension winch. The extension determination member may comprise a second cable which forms the branched portion. The second cable may at one end be connected to the first cable by a cable connector, e.g a swivel, and at the other end connected to the foundation casing.

[0071] Advantageously, the branched portion of the extension determination member transfers a ramming load at the end of an extension stroke directly to the foundation casing in stead of to the extension winch. The branched portion carries possible high loads which may prevent the extension winch from damages. Herewith, a robust blockage of the extension of the foundation casing may be achieved.

[0072] In an embodiment of the method according to the invention, the method further comprises a steps of withdrawing the foundation casing from the ground so that a hole is left in the ground and introducing a setting substance into the hole. Preferably, the extension determination member is kept under a predefined tension during a withdrawal of the foundation casing. Preferably, the tension is generated by an extension winch which is connected to the opposite end of the extension determination member. Due to the tension, the extension determination member is kept substantially straight during withdrawal of the foundation casing. The extension determination member may remain free from loops or bends which could result in damages to the obtained hole.

[0073] In an embodiment of the method according to the invention, the foundation casing is withdrawn by a hoisting device including at least one hoisting cable, wherein the hoisting cable is connected to the distal end of the foundation casing and extends outside along the foundation casing.

[0074] The invention further relates to a set of piling tools for carrying out a method according to the invention.

[0075] The set of piling tools according to the invention is suitable to carry out a piling method to create a pile in the ground. The set of piling tools comprises a hollow foundation casing including at least an inner and an outer pipe segment which are telescopically connected to each other. The foundation casing is extendable from a collapsed configuration to an extended configuration by moving the inner pipe segment at least partially out of the outer pipe segment.

[0076] The set op piling tools is improved in that a longitudinal extension determination member is provided which is at one end connected to a distal end of the inner pipe segment. In particular, the extension determination member comprises a cable. Preferably, the extension determination member is bendable. The extension determination member may comprise at least one marking to indicate at least one part of a length of the extension determination member.

[0077] In an embodiment of the set of piling tools according to the invention an opposite end of the extension determination member is connected to an extension winch. Preferably, the extension winch has a rotor which is drivable in rotation by a motor for winding the extension determination member. The extension winch may be connected to the foundation casing. In particular, the extension winch is connected to a proximal end of the foundation casing in particular to the proximal end of the outer pipe segment.

[0078] In an alternative embodiment according to the invention the extension winch is connected to a pile driving device, in particular to a derrick or guidance of a pile driving device.

[0079] In an embodiment of the set of piling tools according to the invention at least two extension determination members are connected to the distal end of the inner pipe segment. The at least two extension determination members may carry loads during ramming when the foundation pile is in the extended configuration. Advantageously, a resulting force will act about a central axis of the foundation casing.

[0080] In an embodiment of the set of piling tools according to the invention at least one hoisting cable and at least one extension determination member is connected to the distal end of the foundation casing.

[0081] In an embodiment of the set of piling tools according to the invention the set op piling tools is arranged at a vehicle

[0082] Further preferred embodiments are defined in the subclauses.

[0083] The invention will be explained in more detail with reference to the appended drawings. The drawings show a practical embodiment according to the invention, which may not be interpreted as limiting the scope of the invention. Specific features may also be considered apart from the shown embodiment and may be taken into account in a broader context as a delimiting feature, not only for the shown embodiment but as a common feature for all embodiments falling within the scope of the appended clauses, in which:

Fig. 4 shows in a schematic view a set of piling tools which are arranged on a vehicle.

Fig. 4 shows in a schematic view a set of piling tools which are arranged on a vehicle. The set of piling tools comprises a pile driving device 50, a hoisting device 40 and a foundation casing 30.

[0084] The pile driving device comprises a derrick 51. The derrick is an elongated element, a mast, to reach several meters, in particular at least 5 meters, above ground level. The derrick is arranged at a front region of the vehicle. The derrick is shown in a working position, in which the derrick is positioned in upright position. The derrick may be rotated to a transport position, in which the derrick is positioned substantially horizontal. The pile driving device further comprises a derrick winch 53 including a derrick cable 52 which extends from the derrick winch over the derrick into the foundation casing 30. In a piling method, the pile driving device with derrick may be used to bring the foundation casing 30 in upright position and to lift and lower a pile driving ram inside the hollow foundation casing. The pile driving device further comprises a guidance 54 to guide the foundation casing 30 when lowered into the ground.

[0085] The foundation casing 30 is in a collapsed configuration before starting a ramming operation. The foundation casing 30 is hollow. The foundation casing has an open proximal end for introducing the pile driving ram into an interior. The foundation casing 30 comprises at least two telescopically connected pipe segments. A length direction of the foundation casing 30 defines an axial direction. The foundation casing 30 has an outer pipe segment 3.9 and an inner pipe segment 3.1. The foundation casing 30 may further comprise at least one intermediate pipe segment to achieve a desired maximum length of the foundation casing in an extended configuration. The telescopically connected pipe segments are axially movable with respect to each other.

[0086] The inner pipe segment 3.1 of the foundation casing has a thickened portion 31 at its distal end. At the distal end, the inner pipe segment 3.1 is connected to an extension determination member 61, in particular an extension cable or chain. The extension cable 61 has a fixed distal end which is connected to the inner pipe segment 3.1. The extension cable 61 extends from the distal end of the inner pipe segment 3.1 towards the proximal end of the outer pipe segment 3.9 above ground level. The extension cable extends outside along the foundation casing 30. Advantageously, the extension determination member 61 provides an indication of a reached extension of the foundation casing and is indicative for a reached depth in the ground.

[0087] An opposite end of the extension cable 61 is winded by an extension winch 62. The extension winch 62 is connected a few meters above ground level to the set of piling tools. The extension winch is connected to the foundation casing 30. Alternatively, the extension winch 62 may be connected to the derrick 51 or guidance 54. The extension winch 62 is pretensioned or driven by a motor to keep the extension determination member 61 at a predefined tension during piling operations.

[0088] A second cable 63 is provided which serves as a blocking member for blocking the first extension cable 61 when a predefined depth extension of the foundation casing is reached. The blocking member connects the opposite end of the extension cable 61 to the foundation casing. The blocking member 63 defines a maximum length of the foundation casing 30 in the extended configuration. The second cable is connected at a first end to the foundation casing and at a second end to the first cable 61 at an intermediate position of the first cable 61. In the collapsed configuration of the foundation casing 30, the second cable is untensioned. In the extended positon of the foundation casing 30, the second cable is tensioned. If a ramming operation is further proceeded with a foundation casing 30 in the extended configuration, the outer pipe segment 3.9 will also lower into the ground. Herewith, an operator has an opportunity to bring the proximal end of the foundation casing close to ground level when finishing the piling operation. This may be advantageous when filling the foundation casing with setting substance.

[0089] Further, the set of piling tools comprises a hoisting device 40. The hoisting device 40 is provided at a lower front region of the vehicle. During piling operations the hoisting device 40 may be installed on the ground. The hoisting device 40 is provided for withdrawing the foundation casing 30 out of the ground. The hoisting device 40 comprises at least one hoisting winch 42 including a hoisting winch 43 which is mounted on a framework 41. An end of the hoisting cable 43 is winded round the hoisting winch 42. A distal end of the hoisting cable 43 is connected to the distal end of the foundation casing.

[0090] Numerous variants are possible in addition to the embodiment shown. Alternatively, an extension determination member including links may be used. Alternatively, the extension determination member may be blocked by a bracket to prevent further extension which bracket may be fixed to an outer wall portion of the outer pipe segment. The bracket may be fixed at a distal end of the outer pipe segment.

[0091] Although the invention has been disclosed with reference to particular embodiments, from reading this description those of skilled in the art may appreciate changes and modification that may be possible from a technical point of view but which do not depart from the scope of the invention as described above and defined in clauses hereafter. It will be understood by those of skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. Modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention is not to be limited to the particular embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of the appended clauses.

[0092] Thus, the second aspect of the invention provides a piling method and a set of piling tools to carry out the piling method including an improvement to warrant a desired extension of a used foundation casing.

[0093] The invention is further described by the following clauses:

1. Method for creating a pile in the ground, comprising the steps of:

• providing a set of piling tools, wherein the set of piling tools comprises a hollow foundation casing (30) including at least an inner (3.1) and an outer (3.9) pipe segment which are telescopically connected to each other, in which the foundation casing is extendable from a collapsed configuration to an extended configuration by moving the inner pipe segment at least partially out of the outer pipe segment;
• positioning the foundation casing in the collapsed configuration in upright position, in which a distal end of the foundation casing is positioned at ground level;
• introducing a pile driving ram at the proximal end into the hollow foundation casing;
• ramming onto a pipe segment to lower the foundation casing into the ground; characterised in that the provided set of piling tools further comprises a longitudinal extension determination member (61), wherein the method further comprises the step of:
• connecting one end of the extension determination member (61) to a pipe segment;
• introducing the extension determination member together with the foundation casing into the ground, wherein an opposite end of the extension determination member is kept above ground level;
• determining an extension of the foundation casing by determining a corresponding length of the extension determination member.

2. Method according to clause 1 comprising the step of connecting the opposite end of the extension determination member (61) to the set op piling tools, in particular to the foundation casing (30).

3. Method according to clause 2, wherein the opposite end of the extension determination member (61) is connected to the proximal end of the foundation casing (30).

4. Method according to any of the preceding clauses, wherein the opposite end of the extension determination member is winded round an extension winch (62), such that the extension determination member (61) extends along the foundation casing.

5. Method according to any of the preceding clauses, wherein an axial movement of the extension determination member (61) is blocked by a blocking member (63), in particular a branched portion, which has an end which is connected at an intermediate position to the extension determination member (61) and at an opposite end to the foundation casing.

6. Method according to any of the preceding clauses, wherein the method further comprises the steps of withdrawing the foundation casing (30) from the ground so that a hole is left in the ground and introducing a setting substance into the hole, wherein the extension determination member (61) is kept under a tension during a withdrawal of the foundation casing.

7. Set of piling tools for carrying out a piling method to create a pile in the ground comprising a hollow foundation casing (30) including at least an inner (3.1) and an outer (3.9) pipe segment which are telescopically connected to each other, in which the foundation casing (30) is extendable from a collapsed configuration to an extended configuration by moving the inner pipe segment at least partially out of the outer pipe segment, characterised in that a longitudinal extension determination member (61) is provided which has an opposite end and a fixed end which connected to a distal end of the inner pipe segment (3.1).

8. Set of piling tools according to clause 7, wherein the opposite end of the extension determination member is connected to an extension winch (62).

9. Set of piling tools according to clause 7 or 8, wherein the opposite end of the extension determination member (62) is connected to the foundation casing (30) or pile driving device (50).

10. Set of piling tools according to any of the clause 9, wherein the extension winch (62) is connected to a proximal end of the foundation casing.

11. Set of piling tools according to clause 9, wherein the extension winch (62) is connected to a derrick (51) or guidance (54) of the pile driving device.

12. Set of piling tools according to any of the clauses 8-11, wherein the extension winch is drivable by a motor.

13. Set of piling tools according to any of the clauses 7-12, wherein at least two extension determination members are connected to the distal end of the inner pipe segment (3.1).

14. Set of piling tools according to any of the clauses 7-13, wherein at least one hoisting cable (43) and at least one extension determination member (61) is connected to the distal end of the foundation casing (30).

15. Set of piling tools according to any of the clauses 7-14, wherein the set op piling tools is arranged at a vehicle.

Claims

1. Method for creating a pile in the ground, comprising the steps of:

- providing a set of piling tools comprising:

- a hollow foundation casing which comprises at least one pipe segment in which the foundation casing is provided with a ramming surface to lower the foundation casing into the ground;

- a pile driving device (50) for introducing the foundation casing (30) into the ground, in which the pile driving device comprises a derrick, a derrick winch and a pile-driving ram; and

- positioning the hollow foundation casing in up right position at a working space, such that a distal end of the foundation casing is positioned at ground level and a proximal end of the foundation casing is positioned above ground level;

- introducing the pile driving ram into the foundation casing at the proximal end of the foundation casing;

- ramming the pile-driving ram against the ramming surface of the foundation casing to lower the foundation casing into the ground;
characterised in that the provided set of piling tools further comprises a hoisting device (40) for withdrawing the hollow foundation casing (30) out of the ground
, wherein the hoisting device comprises at least one hoisting winch (42) which is connected to a framework (41) to wind at least one hoisting cable (43) in which a free end of the hoisting cable is connectable to the at least one pipe segment (3.1), wherein the method further comprises the steps of:

- positioning the framework of the hoisting device at ground level adjacent the foundation casing;

- connecting the at least one free end of the at least one hoisting cable to an outer surface of the pipe segment at the distal end of the foundation casing;

- withdrawing the at least one pipe segment (3.1) out of the ground by driving the at least one hoisting winch (42) of the hoisting device,

2. Method according to claim 1, wherein the used hoisting device (40) has a compact configuration, in particular maximum outer dimensions of at most 1 meter in height and at most 2 meters, more in particular at most 1 meter in width and length..

3. Method according to claim 1 or 2, wherein the used hoisting device (40) comprises at least two hoisting winches (421,422) including respectively at least two hoisting cables.

4. Method according to claim 3, wherein the hoisting winches (421,422) are positioned opposite each other adjacent the foundation casing.

5. Method according to any of the preceding claims, wherein a vehicle is used, wherein the set of piling tools is arranged on the vehicle (2), wherein the vehicle comprises an operating unit to at least partially operate the set of piling tools.

6. Method according to any of the preceding claims, wherein the method comprises at least one of the following features:

- wherein the foundation casing (30) comprises at least two telescopically connected pipe segments;

- wherein the used foundation casing further comprises a releasable base plate (10), which base plate provides a ramming surface and forms a closed distal end of the hollow foundation casing;

- wherein the pile-driving ram is moved down and in the first instance rams the base plate, in such a way that the base plate drops a certain distance, after which in the second instance the pile-driving ram rams the pipe segment, in such a way that the pipe segment drops;

- wherein the method comprises further the following steps: positioning a hollow foundation case (30) including a base plate (10); moving a pile-driving ram up with the pile-driving device; moving the pile-driving ram down through the foundation casing; letting the pile-driving ram the base plate and the foundation casing; withdrawing the foundation casing from the ground using the hoisting device (40), so that a hole is left in the ground; leaving the base plate behind in the hole that is left; and introducing a setting substance on top of the base plate in the hole that is left;

- wherein in a step of the method a reinforcement member is provided in the hole that is left.

7. Set of piling tools in particular for carrying out the method according to any of the preceding claims to create a pile in the ground, in which the set comprises:

- a hollow foundation casing (30) which comprises at least one pipe segment, in which the foundation casing has a ramming surface to lower the foundation casing into the ground by ramming;

- a pile driving device (50) for introducing the foundation casing (30) into the ground, in which the pile driving device comprises a derrick, a derrick winch, a derrick cable and a pile-driving ram to ram onto a ramming surface of the foundation casing; and

- a hoisting device (40) for withdrawing the hollow foundation casing (30) out of the ground , wherein the hoisting device comprises at least one hoisting cable which is at one end connectable to an outer surface of the at least one pipe segment and at the other end winded round a drivable hoisting winch, wherein the hoisting winch (42) is arranged on a ground based framework, such that a hoisting cable extends directly from the hoisting winch to the ground.

8. Set of piling tools according to claim 7, wherein the hoisting device comprises a first and second hoisting winch (421,422), wherein the first hoisting winch is arranged on a platform opposite the second hoisting winch, wherein the passageway for the foundation casing (30) is positioned in between the first and second hoisting winch.

9. Set of piling tools according to claim 7 or 8, wherein the framework of the hoisting device includes a passageway (44) to allow the foundation casing to pass through the framework into the ground, wherein the at least one hoisting winch is positioned adjacent the passageway.

10. Set of piling tools according to any of the claims 7-9 comprising at least one of the following features:

- wherein the framework (41) of the hoisting device is a platform;

- wherein the framework (41) has a compact configuration, wherein the framework has outer dimensions of at most 1 meter in height and at most 2 meters in width and length;

- wherein the framework (41) of the hoisting device has a window frame shape, wherein the open area of the window frame serves as a passageway;

- wherein the framework (41) has ground supporting means to position the framework on the ground.

11. Set of piling tools according to any of the claims 7-10, wherein the set of piling tools are arranged on a vehicle (2).

12. Set of piling tools according to claim 11, wherein the vehicle (2) comprises at a front region a derrick (50) for positioning and introducing a foundation casing, wherein the derrick is rotatable mounted to the vehicle about a horizontal axis to bring the derrick from a transport in a standing working position, wherein the vehicle (2) further comprises a hoisting device (40) at a lower front region.

13. Set of piling tools according to claim 12, wherein the hoisting device (40) is connected to the derrick (50) in a lower region of the derrick.

14. Set of piling tools according to any of the claims 7-13, comprising at least one of the following features:

- wherein at least one pipe segment of the foundation casing (30) is provided with a thickened portion at the distal end, wherein the at least one hoisting cable (43) is connectable to the thickened portion of said pipe segment and wherein the thickened portion includes both a ramming surface for lowering the pipe segment and a through hole for passing the pile-driving ram, wherein the pile-driving ram is designed to ram the foundation casing into the ground by hitting in a first instance against the base plate (10) and in a second instance against the ramming surface of one of the pipe segments;

- wherein the foundation casing comprises a baseplate (10), wherein the baseplate comprises an external collar wall for surrounding a distal end of a pipe segment of the hollow foundation casing (30);

- wherein the foundation casing (30) comprises at least two telescopically connectable pipe segments;

- wherein the foundation casing comprises an assembly of individual pipe segments which individual pipe segments are slidably insertable into each other.

15. Vehicle (2) comprising the set of piling tools according to any of the claims 7 - 14.

Drawing