WO2003010391A1

WO2003010391A1 - Ground anchor with driving and opening device

Info

Publication number: WO2003010391A1
Application number: PCT/PL2002/000054
Authority: WO
Inventors: Józef KARDA
Original assignee: Karda Jozef
Priority date: 2001-07-23
Filing date: 2002-07-22
Publication date: 2003-02-06
Also published as: PL199940B1; PL348854A1

Abstract

A ground anchor with a tension member comprising two plates (l) linked jointly by a pin (2), the plates having an assembly linking them with a tension member (3) at the end of which, on the plates (l) side, a pin (8) provided with a head (9) is located . A device for injecting and opening of the ground anchor in the ground according to the invention comprises a mounting member (12) placed on the anchor tension member (3) that projects from the mounting member (12) through an opening in the cover (15) covering the mounting member (12) , and on which a drive sleeve (18) is screwed down, the drive sleeve being provided with a catch (17), a nut (19) fixing the position of the catch (17) and a spacer washer (l6), and the mounting member is connected through the cover (15) with the body (24) by means of two stretching bolts (21) provided with nuts (20,22)

Description

GROUND ANCHOR WITH DRIVING AND OPENING DEVICE

The present invention relates to a ground anchor and a device for injecting and opening the ground anchor in the ground. Ground anchors are utilized in building structures for anchoring loaded elements of these structures in the surrounding ground in order to maintain their stability.

An injection-type ground anchor is known and commonly used, the in-ground anchoring member (support) of which being an elongated club consisted of bound cement grout, made by filling a prepared deep (20 - 30 m) round hole using various techniques of injection. A tension member is embedded into the club during the injection process. Both rigid as well as rope tension members are utilized. Length of such a club ranges from 6 to 10 m and its diameter from 20 to 50 cm, depending on type of the ground, injection technique and diameter of the prepared hole.

Load capacity of such a ground anchor is a resultant of the friction of the club side surface against the surrounding ground. After usage, there is practically no possibility of removing it from the ground. It may cause significant problems while building other deeply embedded objects in the same area, happening more and more frequently in urban areas.

The ground anchor with a tension member according to the invention is characterized in that it comprises two plates linked with a joint, the plates having an assembly linking them with the tension member at the end of which a pin is located provided with a head.

The linking assembly consists of arms attached jointly by pins to the plates with the first end and to the nut of the tension member with the other end. Preferably, each of the plates is provided with two arms and the nut is cuboidal with length proportion of the sides 1:1:4.

Furthermore, the arms are attached to the plates asymmetrically relative to their centers of gravity, preferably at the distance equal to 2/5 of the span from the pin of the joint junction of the plates.

Preferably, the tension member is a bar tension member.

The parallel to the pin sides of the plates are beveled, preferably at an angle of 45° and each of the plates is provided with two catches placed at the beveled sides.

The plates are rectangular sheets with side length proportion of 5:6.

The head is mounted on the tension member ended with the pin by a perpendicularly placed thereto latch.

The tension member is placed in a mounting member having a form of a tube of rectangular cross-section area and sides length proportion 1:2.

Moreover, the mounting member has a tip member being beveled at both sides and defining parallel isosceles triangles with the apex angle of 35°.

The mounting member is closed at its second end with a cover through which the tension member projects.

The head width is equal to the inner width of the mounting member.

The angle of opening of the plates ranges from 35° to 330°.

According to the invention, the device for injecting and opening the ground anchor is characterized in that the mounting member is placed on the anchor tension member that projects from the mounting member through an opening in the cover covering the mounting member, and on which a drive sleeve is screwed down, the drive sleeve being provided with a catch, a nut fixing the position of the catch and a spacer washer, and the mounting member is connected through the cover with the body by means of two stretching bolts provided with nuts .

Furthermore, the tension member tip is rotatably locked by the back wall of the body the tip passes through.

The stretching bolts have various threads in locations of nuts .

The cover possesses sockets forming rotatable slidable bayonet joints for coupling the stretching bolts through the nuts, and the cover sockets have members locking rotation of the nuts, the nuts being of elongated shape.

The drive sleeve forms a hollow bolt with a female thread.

Both the cover and the catch have openings the diameters of which are equal to the external diameter of the external thread of the drive sleeve.

The catch has sockets forming rotatable slidable bayonet joints for coupling the stretching bolts through the nuts, and preferably the catch sockets have members locking rotation of the nuts.

The spacer washer is a slip washer.

Moreover, the mounting member forms a tube with rectangular cross sectional area the side length proportion of which is 1:2. The mounting member has two parallel sides ended with isosceles triangles with the apex angles of 35°.

A cylindrical guide is placed along the axis of the tension member on the anchor at the front end. The structure of the anchor allows for injecting it into the ground in collapsed state and opening it at the desired location by means of the device according to the invention, similarly to opening of an umbrella.

Embodiment of the present invention is presented in reference to the accompanying drawing wherein

Fig. 1 shows a horizontal section of the opened anchor;

Fig. 2 shows a vertical section of the opened anchor;

Fig. 3 shows a horizontal section of the device for injecting and opening of the anchor in the ground together with the collapsed anchor;

Figs. 4 and 5 illustrate successive phases of operation of this device.

In reference to fig. 1 the anchoring portion according to the invention is a rectangular steel plate located at the end of a rigid tension member in the plane perpendicular to its axis .

The anchor is formed by two rectangular plates 1 (length proportion 5:6) linked jointly along the longer side by the pin 2 (as a strap hinge) so as to allow opening angle to be in the range from 35° to 330°. During injecting into the ground in the collapsed state the angle is 35° whereas after opening for the final operational position the angle is 180°. In the case of utilizing the anchor as a temporary anchor the opening angle may reach the value of 330°, that allows for removing the whole anchor the same way it was injected. The sides of the plates 1 parallel to the pin 2 are beveled preferably at an angle of 45°. Each of the plates _1 is provided with two catches 10 placed adjacently to the beveled sides.

A steel bar threaded at both ends forms the tension member 3 of the anchor. Attachment of the tension member 3 with plates 1 is embodied by means of the nut _4 in a form of elongated cuboid (size proportion 1:1:4) being in turn linked jointly with the both plates 1 through pins 7_ by means of two arms 5 caught asymmetrically relative to centers of gravity of the plates 1 . The arms 5 are attached to plates 1 by means of pins 6. They are located at the distance equal to 2/5 of the span from the pin 2 of the joint junction of the plates 1_. Supporting of the sides of the plates 1 linked with the joint 2 upon the tip of the tension member 3 ended with the head 9 and screwed into the nut enables stabilizing of full opening (180°) of the plates 1_. They create a plane with dimensions 10:6 (2 x 5:6) located perpendicularly to the axis of the tension member 3. The tension member is ended with the pin _8 on which a specifically shaped head 9 is seated through the catch 1_1. Screwing of the tension member 3_ into the nut _4 causes that the head 9_^ approaches the plates 1 .

The tension member _3 is mounted in the mounting member 12_

(figs. 1, 3) formed by a tube of rectangular cross-sectional area and sides length proportion 1:2. The mounting member 1_2 has a tip member being beveled at both sides and defining parallel isosceles triangles with the apex angle of 35°.

The head 9_ has width equal to inner width of the mounting member 12.

The mounting member _12 may be a protective member for the tension member _3 when left in the ground together with the anchor but it serves primarily for injecting the anchor into the ground.

The plates 1 folded to an angle of 35° mounted on the mounting member _12 define a gable roof - the wedge compressed by the tension member 3_ placed inside the mounting member 12, by means of the nut 19 located at its second end and abutted against the cover 1_5 through the drive sleeve 1_8 and catch 1_7_ with the washer 16_. With such an engagement a picket-like collapsed element ended with a wedged arrowhead is obtained.

The so prepared "picket" can be injected into the ground quite easily, for example into a prepared round drilled hole of a proper diameter. For guaranteeing the axial injecting of the picket into the round hole the cylindrical guide _14 (fig. 3) is mounted onto the arrowhead. After injecting and opening of the anchor into the ground the mounting member 1_2 is pulled out and may serve for a subsequent use.

The anchoring plate surface area is about 3.5 times bigger than the cross-sectional area of the hole through which it has been injected into the ground thereby high enough resistance is obtained when loading the plate with a force applied along the axis of the caught thereto tension member 3_.

Opening of the anchor in the ground proceeds in two stages. In the first phase the tension member _3 being screwed into the nut 4_ causes expanding of the plates 1_ by action of the head 9 . In this stage the angle of opening of the plates reaches the value of about 72°. The locked tension member _3 stays in place whereas the plates _1 move onto its head _9 opening to both sides.

In the second phase upon the axial force applied to the tension member _3 the opening of the anchor continues in consequence of abutting of the side beveled edges of the plates 1 against the ground.

The full opening takes place when the angle of opening of the plates 1_ reaches 180°, as shown in fig. 1.

The edges of the plates 1 along the pin 2 will abut then against the head 9 preventing further deflecting of the plates 1 . Evident resistance felt when stretching the tension member 3 indicates that the opening of the plate is completed. This is the operating position. Figs 3 - 5 present a device for injecting and opening the ground anchor comprising two stretching bolts 2_1 with nuts 20, 22 caught against the cover 5 and the catch 17. The stretching bolts 2_1 have various threads in locations of the nuts 2_0 and 2_2. The screwed drive sleeve 1_8 is located on the tension member _3 projecting from the mounting member _12 through an opening in the cover 5, the catch _17 operating as a whippletree with the spacer washer 1_6 as well as the nut 1_9 for fixing a proper position of the catch jL7_ along the drive sleeve j^8 and coupling the entire anchor with the mounting member _12 being mounted slidingly on the drive sleeve 18.

The nuts 2_0 are elongated.

The drive sleeve V8 forms a hollow bolt with internal thread.

The cover _15_ and catch 1_7 have openings of diameters equal to external diameter of the external thread of the drive sleeve 1_8. Furthermore, the catch 1_7 possesses sockets forming rotatable slidable bayonet joints for coupling the stretching bolts 2_1 through the nuts 2_2. The sockets of the catch 17_ have members 2_5 locking rotation of the nuts 22.

The spacer washer 16 is a slip washer.

The tip of the tension member 3_ passes through the back wall of the device body 2_4 and is rotatably locked by it.

The opening of the anchor proceeds in the following subsequent operations. After the tension of the nut 1_9 is released and the nut is undone to the end of the drive sleeve 18 the stretching bolts 21 are activated. Their revolution (screwing in) causes initial pulling out of the mounting member 1_2 by means of travelling nuts 2_0 until abutting of the cover _15_, washer 1_6 and the catch _17 against the formerly unscrewed nut _19, as is shown in fig. 1 - phase 1, as denoted by arrows 1, 2. Then the executed revolutions (screwing in) of the tension member 3_ cause initial opening of the plates 1 moved onto the head 9 as well as travelling of the drive sleeve 1_8 towards the back wall of the body 2_4, as is shown in fig. 1 - phase 2, as denoted by arrows 3. Then the catch 17_ should be put onto the nuts 22_ on the stretching bolts 21 and locked by the screwed thereto nut 1_9, fig. 4 - phase 2, arrow 4 and fig. 5 - phase 3, arrow 5. Now, further revolution of the stretching bolts 21 causes pulling out of the tension member _3 by means of the drive sleeve ^8 and simultaneous pulling out of the mounting member _12 from the ground, fig. 5 -phase 4, arrow 6. Pulling out of the tension member in this phase causes final opening of the plates 1 to the final position of 180°. Occurrence of evident resistance indicates completing of opening of the anchor.

An additional driving mechanism 3 activated by an assembly of toothed gears is used to execute opening of the anchor plates, not being a subject of the present invention. .

All subsequent movements (revolutions of bolts, nuts, shifts) of the aforesaid components of the device have precisely determined values. It guarantees the proper process of opening the anchor in the ground. Yet complete pulling out of the mounting member 12_ and dismantling of all the elements from the tension member is to be done. The anchor is ready for stretching.

The present invention may be utilized for anchoring of sheet pile walls, cavity walls used as steenings, retaining walls, steenings and tunnels, anchoring of masts and poles. Embedding into the ground is possible at any angle: from vertical downward to vertical upward (for example, for supporting the ceiling of a tunnel) . It may be particularly useful in emergency situations because it may be loaded up to its nominal load capacity immediately after embedding. It may be entirely removed from the ground after usage as a temporary anchor and used again (provided not being permanently damaged or after replacing a damaged element only) .

Load capacity of an anchor of this type is practically unlimited. It depends on depth of embedding, ground conditions and strength parameters of materials used for making it.

Claims

1. A ground anchor having a tension member characterized in that it comprises two plates (1_) linked jointly by a pin (2_) , the plates having an assembly linking them with a tension member (3_) at the end of which, on the plates (_1) side, a pin

(8_) provided with a head (_9) is located.

2. The ground anchor according to claim 1 characterized in that said linking assembly comprises arms (_5) attached to the plates (1_) through pins (6_) with the first end and to the nut

(4_) of the tension member (3) through pins (_7) with the other end.

3. The ground anchor according to claim 2 characterized in that each of said plates (1) is provided with two arms (_5) .

4. The ground anchor according to claim 2 characterized in that said nut (_4) is cuboidal with side length proportion 1:1:4.

5. The ground anchor according to claim 2 or 3 characterized in that the arms (_5) are attached to said plates (1_) asymmetrically relative to their centers of gravity.

6. The ground anchor according to claim 5 characterized in that the arms (_5) are attached to said plates (1) at the distance equal to 2/5 of the span from the pin (2) .

7. The ground anchor according to claim 1 or 2 characterized in that said tension member (3_) is a bar tension member.

8. The ground anchor according to claim 1 characterized in that the sides of the plates (1_) parallel to the pin ( 2 ) are beveled preferably at an angle of 45°.

9. The ground anchor according to claim 1 or 8 characterized in that each of the plates (_1) is provided with two catches (10) placed at the beveled sides.

10. The ground anchor according to claim 1 characterized in that said plates (_!) are rectangular sheets with side length proportion of 5:6.

11. The ground anchor according to claim 1 characterized in that said head (9_) is mounted on the tension member (3_) ended with the pin (8_) by a perpendicularly placed thereto latch

(11) •

12. The ground anchor according to claim 1 characterized in that said tension member (3) is placed in a mounting member

(12) .

13. The ground anchor according to claim 12 characterized in that the mounting member (12_) has a form of a tube of rectangular cross-section area and sides length proportion 1:2.

14. The ground anchor according to claim 12 or 13 characterized in that said mounting member (12_) has a tip member being beveled at both sides and defining parallel isosceles triangles (13_) with the apex angle of 35°.

15. The ground anchor according to claim 12 characterized in that said mounting member (12_) is closed at its second end with a cover (1_5) through which the tension member (3) projects .

16. The ground anchor according to claim 1 or 11 characterized in that said head (_9) has width equal to the inner width of the mounting member (12_) .

17. The ground anchor according to claim 1 characterized in that the angle of opening of the plates (_1) ranges from 35° to 330°.

18. A device for injecting and opening of the ground anchor in the ground characterized in that the mounting member (12) is placed on the anchor tension member (3) that projects from the mounting member (12_) through an opening in the cover (JL5) covering the mounting member (12) , and on which a drive sleeve (18_) is screwed down, the drive sleeve being provided with a catch (17_) , a nut (19) fixing the position of the catch { 11 ) and a spacer washer (1_6) , and the mounting member is connected through the cover (1_5) with the body (24) by means of two stretching bolts (2_1) provided with nuts (20,22) .

19. The device according to claim 18 characterized in that the tip of the tension member (_3) is rotatably locked by the back wall of the body (2_4) the tip passes through.

20. The device according to claim 18 characterized in that said stretching bolts (21_) have various threads in locations of nuts (20, 22) .

21. The device according to claim 18 characterized in that said cover (1_5) has sockets forming rotatable slidable bayonet joints for coupling the stretching bolts (21) through the nuts (20) .

22. The device according to claim 21 characterized in that said sockets of the cover (1_5) have members (2_5) locking rotation of the nuts (2_0) .

23. The device according to claim 18 or 22 characterized in that the nuts (2_0) are elongated.

24. The device according to claim 18 characterized in that said drive sleeve (.18) forms a hollow bolt with an inner thread.

25. The device according to claim 18 characterized in that the cover (1_5) and the catch (_17) have openings with the diameter equal to the external diameter of the external thread of the drive sleeve (18) .

26. The device according to claim 18 characterized in that the catch (17) has sockets forming rotatable slidable bayonet joints for coupling stretching bolts (2_1) through the nuts (22) .

27. The device according to claim 26 characterized in that the sockets of the catch (_17) have members (25_) locking rotation of the nuts (22_) .

28. The device according to claim 18 characterized in that the spacer washer (_16i) is a slip washer.

29. The device according to claim 18 characterized in that said mounting member (12) forms a tube of rectangular cross- section area and sides length proportion 1:2.

30. The device according to claim 18 characterized in that said mounting member (12_) has two parallel sides ended with isosceles triangles ( 3) with the apex angles of 35°.

31. The device according to claim 18 characterized in that a cylindrical guide (1_4) is placed along the axis of the tension member (3) on the anchor at the front end.