EP2597203A1

EP2597203A1 - Ground anchor

Info

Publication number: EP2597203A1
Application number: EP12194034.0A
Authority: EP
Inventors: Johannes Franciscus Karsten
Original assignee: J F KARSTEN BEHEER BV
Current assignee: J F KARSTEN BEHEER BV
Priority date: 2011-11-24
Filing date: 2012-11-23
Publication date: 2013-05-29
Also published as: NL2007849C2

Abstract

The invention relates to a method for applying a pivoting ground anchor on considerable depth, the anchor comprising;
- a first coupling member for temporary coupling the anchor with a driving rod to drive the anchor to the considerable depth; and,
- a tension member for coupling the anchor to the object to be anchored,
- a second coupling member which fixedly couples the anchor to the tension member,

wherein the tension member is of one piece and has a considerable length for applying the pivoting ground anchor on considerable depth, and wherein the method comprises the step; continuously supplying the tension member to the ground anchor without interruption during driving the ground anchor to the considerable depth.

Description

Background

The present invention relates to a method for applying a pivoting ground anchor on considerable depth.
US 2003/0121219 A1 relates to an apparatus and method for installing a plate or wing-type pivoting ground anchor. The anchor assembly includes an all thread setting rod which is extended to virtually any length by a series of threaded couplings which can be used to secure excessive lengths of setting rod together.
Using these couplings to obtain a setting rod of any length however is cumbersome and time consuming during installation of the ground anchor. In addition, the couplings disturbs the ground around the setting rod which is harmful for the functioning of the ground anchor later on. In addition, the coupling causes additional resistance during application of the ground anchor, which resistance is all the more harmful since it tends to pivot the ground anchor.
US 2008/0282625 A1 discloses in general a pivoting ground anchor, also referred to as earth anchor. In general these ground anchors provide an anchoring point which is able to accommodate considerable loads like typically up to hundreds of kgN.
GB 2 402 686 A relates to a ground drainage apparatus, suitable for draining soils e.g. to reduce pore water pressure behind retaining walls or within clay slopes. A tendon is used to tilt the ground anchor into a locked position. The tendon is then secured in position using a load plate. The tendon does not accommodate an anchoring force and is therefore not considered a tension member for accommodating a considerable anchoring force. Instead the object to be anchored, a length of conduit, is secured to the ground anchor itself. The present invention does not relate to a ground drainage apparatus like the apparatus of GB2402686 .The present invention further relates to a Assembly of a pivoting ground anchor and a tension member.
The present invention further relates to a system for applying a pivoting ground anchor.

Summary of the invention

The invention aims to provide a method for applying a pivoting ground anchor on considerable depth which method is less time consuming and cumbersome.
Another object of the invention is to improve an assembly of a pivoting anchor and a tension member.
Yet another object of the invention is to provide a method for applying a pivoting ground anchor on considerable depth wherein a problem in the prior art is at least partly solved.
Yet another object of the invention is to provide an alternative method for applying a pivoting ground anchor on considerable depth.
According to a first aspect of the invention this is realized with a method for applying a pivoting ground anchor on considerable depth, the anchor comprising;

a first coupling member for temporary coupling the anchor with a driving rod to drive the anchor to the considerable depth; and,
a tension member for coupling the anchor to the object to be anchored,
a second coupling member which fixedly couples the anchor to the tension member such that the anchor pivots when then the tension member is taken in,

The continuous supplying of the tension member results in a less time consuming and less cumbersome method for applying a pivoting ground anchor on considerable depth. In addition, couplings are no longer needed and do not disturb the ground around the tension member.
It will be clear that the tension member being of one piece essentially means a tension member of one length without any coupling member between tension member parts. It is however conceivable that the tension member has for instance a core and an outside cover.
The tension material may comprise any suitable material for anchoring purposes like e.g. steel, or fibre reinforce plastic.
It will be clear for the person skilled in the art that the tension member must be suitable to accommodate considerable loads in order to be able to provide an anchoring point.
In an embodiment of the method, the length of the tension member exceeds 3 meter, preferably exceeds 6 meter, more preferably exceeds 10 m.
In an embodiment, the method comprises the step supplying the tension member from a bobbin. This makes the method even more less time consuming and less cumbersome.
The invention further relates to an assembly of a pivoting ground anchor and a tension member of considerable length for use with the method according to the invention, the anchor comprising;

a first coupling member for temporary coupling the anchor with a driving rod to drive the anchor to the considerable depth; and,
a second coupling member which fixedly couples the anchor to the tension member such that the anchor pivots when the tension member is taken in,

The tension member is coupled with the anchor for setting the anchor in a known manner and for coupling the object to be anchored with the anchor.
In an embodiment of the assembly, the length of the tension member exceeds 3 meter, preferably exceeds 6 meter.
In an embodiment of the assembly, the tension member is of one piece.
In an embodiment of the assembly, the tension member is continuous.
In an embodiment of the assembly, the tension member extends without interruption.
In an embodiment of the assembly, the entire outside surface of the tension member extends without irregularity for reducing resistance during application of the assembly in the ground.
In an embodiment of the assembly the tension member extends from the second coupling member to an object to be anchored without any intermediate coupling members and/or connectors suitable for coupling tension member sections.
In an embodiment of the assembly, the entire tension member is provided with fastening thread for coupling the tension wire to the object to be anchored. This is beneficial since during installation of a pivoting anchor, the tension member is first taken in with the anchor, and subsequently taken out to set the anchor. Thus the all threaded tension member is able to be coupled with the object to be anchored under all circumstances with further means known per se like e.g. nut and washer.
In an embodiment of the assembly, the second coupling member is configured such that the second coupling member can withstand loads to the tension member during application of the assembly with vibratory movement. This is beneficial because the loads to the tension member of considerable length during installation of the anchor are much more severe because initially all the tension member is above ground and not dampened by the ground and thus free to vibrate. In addition, it will be clear the second coupling member is able to withstand tension loads and movement that occur in use of the assembly.
In an embodiment of the assembly, the second coupling member comprises a second coupling member body having a body recess wherein an end of the tension member is accommodated with an interference fit.
In an embodiment of the assembly, the second coupling member body overlaps with the tension member along its longitudinal axis at least with an overlap of at least 4 mm. This enables having sufficient contact surface between the tension member and the second coupling member.
In an embodiment of the assembly, the diameter of the body recess exceeds 2 mm. This even more enables having sufficient contact surface between the tension member and the second coupling member.
In an embodiment of the assembly, the ratio of the overlap and the diameter of the body recess exceeds 1, preferably 1,5.
The invention further relates to a system for applying a pivoting ground anchor, comprising an assembly according to the invention, and a bobbin with a plurality of tension members coiled up around the bobbin.
The invention further relates to a device comprising one or more of the characterising features described in the description and/or shown in the attached drawings.
The invention further relates to a method comprising one or more of the characterising features described in the description and/or shown in the attached drawings.
The various aspects discussed in this patent can be combined in order to provide additional advantageous advantages.

Description of the drawings

The invention will be further elucidated referring to an preferred embodiment shown in the drawing wherein shown in:

Fig. 1 in side view an assembly according to the invention;
Fig.2 a detail of fig. 1; and,
Fig. 3 an assembly of fig. 1 with a schematically depicted bobbin.

Detailed description of embodiments

The invention will be further described in detail referring to an preferred embodiment shown in the figures 1 - 3. In the figure 1 an assembly 15 of a tension member 3 and an anchor 1 is shown. A tension member 3 is known per se and may be a suitable cable or a rod. The anchor 1 is shown in its set position wherein the longitudinal axis 12 of the anchor 1 is substantially transverse with respect to the longitudinal axis 8 of the tension member 3. Anchoring force F is applied to the tension member 3 to anchor an object (not shown) above ground.
The anchor 1 comprises a first coupling member 2 for temporary coupling the anchor with an elongate driving member, like a rod, to drive the anchor to the considerable depth. The first coupling member 2 comprises a first coupling member cavity 11 for accommodating an end of the elongate driving member. The first coupling member cavity 11 is here defined by a cavity wall 16. The first coupling member cavity 11 extends along the longitudinal axis 12 of the anchor 1. The first coupling member cavity 11 and the end of the elongate driving member have a loose fit for temporarily coupling the driving device with the anchor 1 and release the end of the elongate driving member from the first coupling member cavity 11 once the desired depth for the anchor 1 has been reached.
The anchor 1 comprises a tension member 3 for coupling the anchor 1 to the object (not shown) to be anchored. The tension member 3 is of one piece and has a considerable length for applying the pivoting ground anchor 3 on considerable depth. Here, the length of the tension member is 6 meter. Other lengths are conceivable, however the length of the tension member is at least 3 meter.
The tension member 3 is continuous, that is extends continuous from the anchor 1 to the object to be anchored. In other words, the tension member 3 extends without interruption. Interruptions may disturb the ground around the tension member 3 which is undesirable.
Here, the entire outside surface 5 of the tension member 3 extends without irregularity for reducing resistance during application of the assembly 15 in the ground.
In this case, the entire tension member 3 is provided with fastening thread (not shown) for coupling the tension member 3 to the object to be anchored.
The anchor 1 comprises a second coupling member 4 which fixedly couples the anchor 1 to the tension member 3. Here, the second coupling member 4 has a second coupling member body 6 and a fork portion 9. The fork portion 9 forms in interaction with the anchor 1, an eye joint link in a known manner. The anchor 1 is able to hinge with respect to the tension member 3 around the eye joint link axis 10.
The second coupling member 4 is configured such that the second coupling member 4 can withstand loads to the tension member 3 during application of the assembly 1 into the ground with vibratory movement. The loads to the second coupling member 4 are significantly higher because of the undampened oscillations of the tension member 3 of one piece and having a considerable length for applying the pivoting ground anchor 3 on considerable depth.
The second coupling member 4 comprises a second coupling member body 6 for providing strength to the second coupling member 4. The second coupling member body 6 is provided with a body recess 7. The body recess 7accommodates an end of the tension member 3 with an interference fit for providing the required strength.
The second coupling member body 6 overlaps with the tension member along its longitudinal axis 8 at least with an overlap L_o of at least 4 mm. The diameter D of the body recess exceeds 2 mm. Depending on the load to be anchored, an increased diameter of the body recess 7 and the tension member is conceivable like 20 mm or even more. The ratio of overlap L_o and the diameter D of the body recess 7 L_o /D exceeds 1, preferably exceeds 1,5, even more preferably exceeds 2.
When in use the pivoting ground anchor 1 is applied on considerable depth, the following method step is taken: The tension member 3 is continuously supplied to the ground anchor 1 without interruption during driving of the ground anchor 1 to the considerable depth. The tension member 3 may be supplied from a bobbin 17 which is schematically shown in fig. 3. The tension member 3 is then subsequently cut of when the desired depth of the anchor 1 is reached. In that case, the assembly 15 is part of a system for applying a pivoting ground anchor 1 in the ground. The system comprises the bobbin with a plurality of tension members 3 coiled up around the bobbin.
Driving of the ground anchor 1 below the ground level 14 involves hammering and/or vibrating the anchor 1 downwards. A driving device (not shown) is therefore coupled with the anchor 1 by an elongate driving member like a driving rod (not shown). The driving device is coupled with the anchor 1 by means of the first coupling member 2. During driving of the anchor 1, the anchor is in its driving position wherein the longitudinal axis 12 of the anchor 1 is substantially parallel with respect to the longitudinal axis 8 of the tension member 3. In the driving position of the anchor 1, the leading edge 13 of the anchor 1 is substantially directed downwards.
It will also be obvious after the above description and drawings are included to illustrate some embodiments of the invention, and not to limit the scope of protection. Starting from this disclosure, many more embodiments will be evident to a skilled person which are within the scope of protection and the essence of this invention and which are obvious combinations of prior art techniques and the disclosure of this patent.

Claims

Method for applying a pivoting ground anchor (1) on considerable depth, the anchor comprising;
- a first coupling member (2) for temporary coupling the anchor with a driving rod to drive the anchor to the considerable depth; and,

- a tension member (3) for coupling the anchor to the object to be anchored,

- a second coupling member (4) which fixedly couples the anchor to the tension member such that the anchor pivots when then the tension member is taken in,
wherein the tension member is of one piece and has a considerable length (l) for applying the pivoting ground anchor on considerable depth, and wherein the method comprises the step; continuously supplying the tension member to the ground anchor without interruption during driving the ground anchor to the considerable depth.
Method according to claim 1, wherein the length (l) of the tension member exceeds 3 meter, preferably exceeds 6 meter.
Method according to claim 1, comprising the step supplying the tension member from a bobbin (17).
Assembly of a pivoting ground anchor and a tension member of considerable length for use with the method according to a preceding claim 1-3, the anchor comprising;
- a first coupling member (2) for temporary coupling the anchor with a driving rod to drive the anchor to the considerable depth; and,

- a second coupling member (4) which fixedly couples the anchor to the tension member such that the anchor pivots when the tension member is taken in,
wherein the tension member (3) is suitable for coupling the anchor to the object to be anchored, and is of one piece and has a considerable length (l) for applying the pivoting ground anchor on considerable depth.
Assembly according to claim 4, wherein the length of the tension member exceeds 3 meter, preferably exceeds 6 meter.
Assembly according to a preceding claim 4-5, wherein the tension member is of one piece, wherein preferably the tension member is continuous, wherein more preferably the tension member extends without interruption.
Assembly according to a preceding claim 4-6, wherein the entire outside surface (5) of the tension member extends without irregularity for reducing resistance during application of the assembly in the ground.
Assembly according to a preceding claim 4-7, wherein the tension member extends from the second coupling member to an object to be anchored without any intermediate coupling members and/or connectors suitable for coupling tension member sections.
Assembly according to a preceding claim 4-8, wherein the entire tension member is provided with fastening thread for coupling the tension wire to the object to be anchored.
Assembly according to a preceding claim 4-8, wherein the second coupling member is configured such that the second coupling member can withstand loads to the tension member during application of the assembly with vibratory movement, and can withstand tensioning loads and movement during use of the assembly.
Assembly according to claim 9, wherein the second coupling member comprises a second coupling member body (6) having a body recess (7) wherein an end of the tension member is accommodated with an interference fit.
Assembly according to claim 11, wherein the second coupling member body overlaps with the tension member along its longitudinal axis at least with an overlap (L_o) of at least 4 mm.
Assembly according to a preceding claim 11 or 12, wherein the diameter (D) of the body recess exceeds 2 mm.
Assembly according to a preceding claim 11-13 wherein the ratio of the overlap (L_o) and the diameter (D) of the body recess exceeds 1, preferably 1,5.
System for applying a pivoting ground anchor, comprising an assembly according to a preceding claim and a bobbin (17) with a plurality of tension members coiled up around the bobbin.