HOLLOW ROD SHEAR CONNECTOR HAVING STATIC MIXING SYSTEM AND METHOD FOR SETTING A HOLLOW ROD SHEAR CONNECTOR IN A ROCK LAYER

Abstract

The disclosure relates to a hollow rod shear connector for stabilizing rock layers in mining, tunnel construction, civil engineering and rock construction, at least having a connector base with one or more outlet channels and a hollow rod which can be fastened to the connector base and comprises a static mixing apparatus adjoining the connector base, a cartridge, divided by a partition into two compartments, for receiving chemical fastening means, and a two-part plunger corresponding to the compartment division, wherein the static mixing apparatus consists of a plurality of mixing elements one behind the other, wherein the flow direction of the chemical fastening means is changed by greater than or equal to 150° and less than or equal to 210° at least twice along the static mixing apparatus. The present disclosure also relates to a method for setting a hollow rod shear connector in a rock layer.

Claims

1. A hollow rod composite anchor for stabilizing rock strata in mining, tunnel construction, civil engineering and rock construction, at least comprising an anchor base comprising one or more outlet channels; and a hollow rod which can be fastened to the anchor base and comprises a static mixing device adjoining the anchor base, a cartridge which is divided into two compartments by a partition wall and is intended to receive chemical fastening agents, and a two-part squeezing plunger corresponding to the compartment division, wherein the static mixing device comprises a plurality of mixing elements arranged one behind the other, wherein the flow direction of the chemical fastening agent along the static mixing device is changed at least twice by greater than or equal to 150° and less than or equal to 210°.

2. The hollow rod composite anchor according to claim 1, wherein the cartridge comprises on the anchor base side an outlet opening to at least one of the outlet channels of the anchor base, wherein the outlet opening of the cartridge is arranged eccentrically to the axis of symmetry of the cartridge.

3. The hollow rod composite anchor according to claim 1, wherein the mixing elements of the static mixing device are present in at least three different mixing element rows, wherein the axes of symmetry of the individual mixing element rows are arranged offset from one another.

4. The hollow rod composite anchor according to claim 3, wherein the different mixing element rows are arranged offset relative to the anchor base along the longitudinal axis of the hollow rod composite anchor.

5. The hollow rod composite anchor according to claim 1, wherein the static mixing device consists of individual mixing elements, wherein the mixing elements have at least two different geometries.

6. The hollow rod composite anchor according to claim 1, wherein the squeezing plunger has an at least three-part symmetrical structure with spaced-apart upper and lower guide lips and central sealing lips, wherein the smallest distance between the outer guide lips and the central sealing lips with respect to the longest extension of the central sealing lips is greater than or equal to 0.25 and less than or equal to 0.75.

7. The hollow rod composite anchor according to claim 1, wherein the two parts of the two-part squeezing plunger are rigidly connected to one another at least via a partition wall cutting device.

8. The hollow rod composite anchor according to claim 7, wherein the two parts of the two-part squeezing plunger are of mirror-symmetrical design and the partition wall cutting device is arranged eccentrically from the common axis of symmetry of the two squeezing plungers.

9. The hollow rod composite anchor according to claim 1, wherein a burst valve is arranged in the at least one outlet channel of the anchor base.

10. The hollow rod composite anchor according to claim 1, wherein the squeezing plunger comprises one or more venting channels along the axis of symmetry of the squeezing plunger.

11. The hollow rod composite anchor according to claim 1, wherein a plastic sheathing with internal spacers is arranged at the outside of the hollow rod composite anchor.

12. The hollow rod composite anchor according to claim 1, wherein the hollow rod comprises fastening means at the point furthest away from the anchor base for mounting a further hollow rod.

13. The hollow rod composite anchor according to claim 1, wherein the hollow rod comprises means for uniquely identifying the hollow rod.

14. A method of setting a hollow rod composite anchor in a rock stratum, wherein the method comprises at least the steps of: a) drilling a hole in a rock stratum to be stabilized; b) setting a hollow rod composite anchor according to claim 1; and c) squeezing the chemical fastening agent from the two compartments through the static mixer and the anchor base by pressurization.

15. The method according to claim 14, wherein in method step c) the pressure load over time per squeezing process is recorded and stored digitally.

Description

DRAWINGS

[0039] The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0040] Further advantages and advantageous embodiments of the subject matter according to the disclosure are illustrated by the examples and drawings and explained in the following description. It should be noted that the drawings are descriptive only and are not intended to limit the disclosure.

[0041] In the figures:

[0042] FIG. 1 schematically shows the structure of a hollow rod composite anchor according to the disclosure;

[0043] FIG. 2 schematically shows the structure of an anchor base with one or more outlet channels that can be used in the hollow rod composite anchor according to the disclosure;

[0044] FIG. 3 schematically shows a static mixing device which can be used in the hollow rod composite anchor according to the disclosure and comprises a plurality of mixing elements disposed one behind the other in a three-mixing row combination;

[0045] FIG. 4 schematically shows a static mixing device which can be used in the hollow rod composite anchor according to the disclosure and comprises a plurality of mixing elements disposed one behind the other in a two-mixing row combination;

[0046] FIG. 5 shows a possible design of the mixing device which can be used in the hollow rod composite anchor according to the disclosure; and

[0047] FIG. 6 shows schematically the design of a squeezing plunger which can be used in the hollow rod composite anchor according to the disclosure;

[0048] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

[0049] Example embodiments will now be described more fully with reference to the accompanying drawings.

[0050] FIG. 1 shows a possible embodiment of a hollow rod composite anchor 1 according to the disclosure. Starting from the deepest point of the borehole, the hollow rod composite anchor 1 comprises an anchor base 3 which comprises one or more outlet channels (not shown) for the exit of a fastening agent from the hollow rod composite anchor 1. Via the outlet channels of the anchor base 3, fastening agent is pressed between the hollow rod composite anchor 2 and the borehole and the hollow rod composite anchor 1 is thus anchored in the borehole. At the anchor base 3 the hollow rod 2 is arranged, which extends over the other functional parts (4, 5, 6) of the hollow rod composite anchor 1 disposed in the interior. Inside the hollow rod 2, adjacent to the anchor base 2, the static mixing device 4 is disposed, in which the fastening agent, for example a two-component adhesive, is mixed before exiting through the anchor base 3. The adhesive is contained in a cartridge 5 divided into two compartments by a partition wall, which cartridge is squeezed by a squeezing plunger 6 by pressurization. In the application, the hollow rod composite anchor 1 is inserted into the borehole and the squeezing plunger 6 is moved, for example via water pressure, in the hollow rod 2 from the point farthest from the borehole in the direction of the anchor base 3. Due to the forces exerted the adhesive is pressed out of the cartridge 5 into the static mixing device 4. Within the mixing device 4, the adhesive is intimately mixed and enters the borehole via the outlet channels of the anchor base 3 and anchors the hollow rod composite anchor 1 in the borehole via the outer anchor walls.

[0051] FIG. 2 shows a possible embodiment of an anchor base 3. The anchor base 3 can comprise an anchor tip in which one or more outlet channels 8 for the fastening agent are arranged.

[0052] FIG. 3 shows a side view of an arrangement according to the disclosure of mixing elements 16 of the static mixing device 4 disposed one behind the other. In this embodiment, the individual mixing elements 16 are combined to form three mixing element rows 9, wherein the row centers form a triangle relative to the direction of the force flux. This means that the mixing element rows 9 with the respective mixing elements 16 connected in series are arranged offset to each other, wherein two different geometries for the individual mixing elements 16 are shown in this representation. The flow of the fastening agent around the mixing elements 16 and rows 9 causes the direction of flow of the fastening agent to be deflected twice by approximately 180° between entry into and exit from the static mixer. The individual mixing element rows 9 and thus also the mixing elements 16 can be arranged offset from each other from the point of view of the force effect, so that different starting points of the mixing element rows 9 are obtained in the direction of the force effect.

[0053] FIG. 4 shows a side view of an arrangement of mixing elements 16 of the static mixing device 4 according to the disclosure arranged one behind the other. In this configuration, the individual mixing elements 16 are combined to form two mixing element rows 9 and the rear row of mixing elements in FIG. 3 has been omitted for the sake of clarity. The individual mixing element rows 9 are each composed of two different mixing elements 10, 11. These two configurations 10, 11 of the mixing elements 16 can contribute to an optimized mixing result without large increase in flow resistance. Relatively large quantities of high-viscosity fastening agent can also be processed with good mixing performance and a squeezing pressure that is not too high.

[0054] FIG. 5 shows a possible enclosure of the mixing device 4 within the hollow rod 2 (not shown). The mixing elements, which may be arranged to form mixing rows, can be easily and securely inserted into the hollow rod and anchored therein by means of this enclosure. The opening 12 of the mixing device points in the direction of the anchor base 3 and the rear 13 of the mixing device 4 points in the direction of the cartridge divided into two compartments (not shown).

[0055] FIG. 6 shows a possible embodiment according to the disclosure of one half of a two-part squeezing plunger 6 according to the disclosure. The second half, not shown, is mirror-symmetrical to the first half 6 and is fixed to the first half by means of a cutting device which is arranged between the two halves 6. In this figure, the upper and lower guide lips 15 and the central sealing lips 14 of the two-part squeezing plunger are shown. By means of this embodiment, even highly viscous fastening agents can be safely squeezed out by the static mixing device. In particular, the risk is reduced that fastening agent is pressed past the squeezing plunger in the direction of the borehole mouth and thus can no longer contribute to the fixing of the anchor in the borehole. In particular, the guide lips can contribute to a smoother movement of the squeezing plunger, wherein tilting is prevented even at high squeezing pressures or during rapid setting processes.

[0056] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are inter-changeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.