Combined grouting anchor rod for tunnel

Abstract

The application provides a combined grouting anchor rod for a tunnel, which comprises an anchor rod head, the anchor rod head is a conical structure, an outer pipe is connected to a larger end of the anchor rod head, an anchor pipe extends along the axial direction of the outer pipe and is screw-connected to one end of the outer pipe corresponding to the anchor rod head through a connecting disc, two limiting rods are symmetrically distributed inside the anchor pipe and are rotationally connected to the connecting disc, two self-expanding mechanisms are respectively distributed corresponding to the two limiting rods, the self-expanding mechanism comprises a first self-expanding piece and a second self-expanding piece, two first slits corresponding to the self-expanding mechanisms are arranged on the anchor pipe, the self-expanding mechanism is used for clamping the inner wall of an anchor hole to keep the stability of the anchor pipe, so that the anchor rod can be prevented from falling before grouting, the grouting effect is ensured, and the problem of low construction efficiency caused by repeated installation of the anchor rod is avoided.

Description

Technical Field

[0001] This invention belongs to the field of tunnel anchor support technology, specifically relating to a combined grouting anchor for tunnels. Background Technology

[0002] Initial anchor bolt support is the core of the New Austrian Tunneling Method (NATM) tunnel lining in mountain tunnels. Hollow grouting anchor bolt technology can maximize the integrity and stability of the surrounding rock, effectively control rock deformation, displacement, and crack development, and fully utilize the supporting role of the surrounding rock itself. It is particularly effective in stabilizing fractured rock masses in karst topography. However, traditional hollow radial anchor bolts are difficult to install, especially during tunnel arch construction. Hollow anchor bolts inserted into the anchor holes often fall off or shift before or during grouting, severely affecting the effectiveness of hollow anchor bolt grouting in reinforcing the rock mass and significantly reducing construction efficiency.

[0003] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art described above. This invention provides a combined grouting anchor for tunnels.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A combined grouting anchor for tunnels, comprising: An anchor head, wherein the anchor head has a tapered structure and an outer tube is connected to the larger end of the anchor head; An anchor pipe, which extends axially into the outer pipe and is threadedly assembled to one end of the outer pipe corresponding to the anchor head via a connecting disc; Two limiting rods are symmetrically distributed inside the anchor pipe and rotatably connected to the connecting plate. The two self-expanding mechanisms are respectively distributed with the two limiting rods. The self-expanding mechanism includes a first self-expanding component and a second self-expanding component. One end of the first self-expanding component is hinged to the connecting plate, and the other end is hinged to one end of the second self-expanding component. The other end of the second self-expanding component is connected to the limiting rod through a threaded sleeve. The anchor pipe is provided with two first strip holes respectively corresponding to the self-expanding mechanism. Two second strip holes are provided on the side of the outer tube, respectively corresponding to the first strip hole. The screw sleeve is driven to move axially along the limiting rod, so that the end of the first self-expanding member and the second self-expanding member connected to each other extends outward or retracts into the second strip hole.

[0006] Preferably, the outer tube has multiple grouting holes.

[0007] Preferably, the side of the threaded sleeve is provided with an ear plate extending out of the first strip hole, and the second self-expanding member is correspondingly hinged to the ear plate.

[0008] Preferably, the first self-expanding member has a groove-shaped structure corresponding to the second self-expanding member, and the end of the second self-expanding member is provided with a hinge shaft that is hinged to the inside of the first self-expanding member.

[0009] Preferably, the inner wall of the first self-expanding member is provided with strip-shaped grooves on both sides corresponding to the hinge shaft and extending along its length direction; An extension sleeve is fitted into the groove between the second self-expanding member and the first self-expanding member. One end of the extension sleeve corresponding to the hinge shaft is provided with a hinge ear that is hinged to the hinge shaft, so that the extension sleeve can be pushed out of the first self-expanding member through the hinge shaft.

[0010] Preferably, the extension sleeve has protrusions on both sides corresponding to the strip groove.

[0011] Preferably, the inner wall of the outer tube corresponding to one end of the anchor head is provided with an internal thread corresponding to the connecting disc.

[0012] Preferably, the limiting rod passes through the connecting plate and has baffles on both sides of the connecting plate to form a rotatable connection with the connecting plate.

[0013] Preferably, the anchor head is provided with multiple grouting holes, and the middle part of the connecting plate is provided with a through hole for connecting the anchor head and the inner cavity of the anchor tube.

[0014] Beneficial effects: The self-expanding mechanism opens and tightens the inner wall of the anchor hole, thereby maintaining the stability of the anchor pipe and preventing the anchor rod from falling off before grouting. This ensures the grouting effect and avoids the problem of low construction efficiency caused by repeated installation of anchor rods.

[0015] The self-expanding components and anchor bolts can be removed for reuse, reducing construction costs. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein: Figure 1 This is a simplified structural diagram of the combined anchor bolt in a specific embodiment of the present invention; Figure 2 This is a schematic diagram showing the connection between the first self-expanding component and the second self-expanding component in a specific embodiment of the present invention.

[0017] Figure 3 This is a schematic diagram of the grouting hole distribution in a specific embodiment of the present invention.

[0018] In the figure: 1. Anchor head; 2. First self-expanding component; 3. Second self-expanding component; 4. Extension sleeve; 5. Limiting rod; 6. Anchor pipe; 7. Outer pipe; 8. Threaded sleeve; 9. Connecting disc; 10. Hinge shaft; 11. Grouting hole; 12. First strip hole; 13. Second strip hole. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0020] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0021] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0022] like Figure 1-3As shown, a combined grouting anchor bolt for tunnels includes an anchor head 1, an anchor pipe 6, limiting rods 5, and a self-expanding mechanism. The anchor head 1 is a conical structure with a bottomless hollow shell. An outer pipe 7 is connected to the larger end of the anchor head 1, and the outer pipe 7 is adapted to the larger end of the anchor head 1. It can be fixed by welding, threaded connection, etc. The diameter of the anchor bolt is smaller than the inner diameter of the outer pipe 7. The anchor pipe 6 extends axially along the outer pipe 7 and is connected to a connecting plate 9, which is adapted to the outer pipe 7 and threadedly assembled to one end of the outer pipe 7 corresponding to the anchor head 1. Limiting rods 5 are provided inside the anchor pipe 6, with two limiting rods 5 symmetrically distributed inside the anchor pipe 6 and rotatably connected to the connecting plate 9. The limiting rods 5 are rod-shaped, and at least the portion corresponding to the inside of the anchor pipe 6 has external threads. Two self-expanding mechanisms are distributed corresponding to the two limiting rods 5, i.e., each self-expanding mechanism is connected to one limiting rod 5, and each limiting rod 5 controls the expansion and retraction of one self-expanding mechanism. Specifically, the self-expanding mechanism includes a first self-expanding component 2 and a second self-expanding component 3. Both the first self-expanding component 2 and the second self-expanding component 3 are strip-shaped components. One end of the first self-expanding component 2 is hinged to the connecting plate 9, and the other end is hinged to one end of the second self-expanding component 3. The other end of the second self-expanding component 3 extends into the anchor pipe 6 and is connected to the limiting rod 5 through the threaded sleeve 8. The limiting rod 5 rotates to drive the threaded sleeve 8 through the thread. The threaded sleeve 8 drives the second self-expanding component 3. As the non-hinged ends of the two self-expanding components approach each other, the hinged ends of the self-expanding components expand outward. The anchor pipe 6 is provided with two first strip-shaped holes 12 corresponding to the self-expanding mechanism. In this embodiment, the hinge shaft 10 of the self-expanding mechanism is perpendicular to the axial direction of the anchor pipe 6, so that it can expand and contract in the plane passing through the two first strip-shaped holes 12 and the axial direction of the anchor pipe 6. Two second strip-shaped holes 13 corresponding to the first strip-shaped holes 12 are provided on the side of the outer tube 7, so that the second strip-shaped holes 13 can be extended or retracted as the threaded sleeve 8 moves back and forth, so as to meet the hole expansion requirements.

[0023] In this embodiment, the length of the outer tube 7 is adapted to the length of the anchor tube 6 and is greater than the depth of the anchor hole.

[0024] In this embodiment, after the device is installed, the self-expanding mechanism is restored to its initial state by manipulating the limiting rod 5 to move outward, and the connecting plate 9 is rotated as a whole to separate the connecting component from the anchor head 1, the anchor tube 6, and the self-expanding mechanism. At this time, only the anchor head 1 and the outer tube 7 remain in the anchor hole.

[0025] In this embodiment, multiple grouting holes are distributed on the outer pipe 7. After the hole is enlarged, a grouting machine can be used to press mortar into the outer pipe 7 through the grouting port. The mortar in the outer pipe 7 seeps into the soil layer through the grouting hole and continues to fill the anchor hole to seal the grouting port and grouting hole 11.

[0026] In an optional embodiment, the side of the threaded sleeve 8 is provided with an ear plate extending out of the first strip hole 12, so that the ear plate can slide and limit the movement along the first strip hole 12, ensuring that the movement can be made along the first strip hole 12 under the action of the thread. The second self-expanding member 3 is correspondingly hinged on the part of the ear plate extending out of the first strip hole 12, so that the reciprocating displacement will not interfere with the movement of the second self-expanding member 3.

[0027] In this embodiment, at least the first self-expanding member 2 is a groove-shaped structure. After the self-expanding mechanism is fully retracted, the second self-expanding member 3 is retracted into the first self-expanding member 2. The end of the second self-expanding member 3 is provided with a hinge shaft 10 that is correspondingly hinged inside the first self-expanding member 2. The screw sleeve 8 is located at the hinge point of the first self-expanding member 2 and the second self-expanding member 3 near the anchor head 1, so that the self-expanding mechanism opens when the screw sleeve 8 is away from the anchor head 1, and retracts when the screw sleeve 8 is close to the anchor head 1.

[0028] In this embodiment, the inner walls of the first self-expanding member 2 are provided with strip-shaped grooves on both sides corresponding to the hinge shaft 10 and extending along its length, so that the second self-expanding member 3 can be inserted into the first self-expanding member 2 after the self-expanding mechanism is fully retracted.

[0029] An extension sleeve 4 is fitted into the slot between the second self-expanding member 3 and the first self-expanding member 2. The extension sleeve 4 is a slotted structure adapted to the first self-expanding member 2 and the second self-expanding member 3. A hinge ear corresponding to the hinge shaft 10 is provided at one end of the extension sleeve 4. When the self-expanding member reaches a certain angle, the extension sleeve 4 is pushed out of the first self-expanding member 2 through the hinge shaft 10 as the first self-expanding member 2 moves continuously, thereby extending the length of the first self-expanding member 2, improving the fixing effect, and avoiding the problem of high recovery difficulty caused by the first self-expanding member 2 having an excessive expansion angle.

[0030] In this embodiment, there is a certain height difference between the upper end of the second strip hole 13 and the junction point of the first self-expanding member 2 and the connecting plate 9. The expansion angle of the first self-expanding member 2 is restricted by the upper end of the second strip hole 13. Specifically, the axial angle between the first self-expanding member 2 and the anchor pipe 6 can be limited to no more than 45 degrees. After the middle part of the first self-expanding member 2 abuts against the upper end of the second strip hole 13, the limiting rod 5 is rotated again, and the second self-expanding member 3 slides along the slide groove, thereby pushing out the extension sleeve 4.

[0031] In this embodiment, there is a damping element between the hinge pin 10 of the first self-expanding member 2 and the strip groove and / or between the extension sleeve 4 and the first self-expanding member 2, or damping is formed by interference fit, so that the extension sleeve 4 will overcome the damping and be pushed out after the first self-expanding member 2 reaches the limit angle.

[0032] In this embodiment, the extension sleeve 4 has protrusions on both sides corresponding to the strip groove, which can improve the fit stability between the extension sleeve 4 and the first self-expanding member 2. The end of the extension sleeve 4 near the hinge shaft 10 has an outwardly protruding flange, and the end of the first self-expanding member 2 has an inner protrusion that blocks the flange, so as to prevent the extension sleeve 4 from detaching from the first self-expanding member 2.

[0033] In this embodiment, the inner wall of the outer tube 7 corresponding to the anchor head 1 is provided with an internal thread corresponding to the connecting disc 9, which can separate the self-expanding mechanism from the anchor head 1, pull out the anchor tube 6 and the various components connected to it, and leave only the anchor head 1 and the outer tube 7 in the anchor hole.

[0034] In this embodiment, the limiting rod 5 passes through the connecting plate 9, and the limiting rod 5 is provided with baffles on both sides of the connecting plate 9 to form a rotatable connection with the connecting plate 9.

[0035] In this embodiment, the anchor head 1 is provided with multiple grouting holes, and the connecting plate 9 has a through hole in the middle for connecting the anchor head 1 and the inner cavity of the anchor pipe 6. A grouting machine is used to press mortar into the outer pipe 7. The mortar in the outer pipe 7 seeps into the soil layer through the grouting holes 11, filling the outer pipe 7 and sealing the grouting holes 11. It should be noted that if the anchor head 1 is horizontally higher than the bottom of the anchor pipe 6, a flexible hose should be inserted into the grouting hole 11 to the anchor head 1 during grouting to ensure that air inside the pipe can be discharged through the hose during grouting.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention shall be within the scope of protection of the pending claims of the present invention.

Claims

1. A combined grouting anchor bolt for tunnels, characterized in that, include: An anchor head, wherein the anchor head has a tapered structure and an outer tube is connected to the larger end of the anchor head; An anchor pipe, which extends axially into the outer pipe and is threadedly assembled to one end of the outer pipe corresponding to the anchor head via a connecting disc; Two limiting rods are symmetrically distributed inside the anchor pipe and rotatably connected to the connecting plate. The two self-expanding mechanisms are respectively distributed with the two limiting rods. The self-expanding mechanism includes a first self-expanding component and a second self-expanding component. One end of the first self-expanding component is hinged to the connecting plate, and the other end is hinged to one end of the second self-expanding component. The other end of the second self-expanding component is connected to the limiting rod through a threaded sleeve. The anchor pipe is provided with two first strip holes respectively corresponding to the self-expanding mechanism. The outer tube has two second slots corresponding to the first slot, which drive the screw sleeve to move axially along the limiting rod, so that the end of the first self-expanding member and the second self-expanding member connected to each other extends outward or retracts into the second slot; The first self-expanding component has a groove-shaped structure corresponding to the second self-expanding component, and the end of the second self-expanding component has a hinge shaft that is hinged to the inside of the first self-expanding component. The inner wall of the first self-expanding member is provided with strip-shaped grooves on both sides corresponding to the hinge shaft and extending along its length direction; An extension sleeve is fitted into the groove between the second self-expanding member and the first self-expanding member. The extension sleeve has a hinge ear at one end corresponding to the hinge shaft, and protrusions on both sides of the extension sleeve corresponding to the groove, so as to push the extension sleeve out of the first self-expanding member through the hinge shaft to extend the length of the first self-expanding member. There is a height difference between the upper end of the second strip hole and the hinge point between the first self-expanding member and the connecting plate, so as to limit the expansion angle of the first self-expanding member through the upper end of the second strip hole. After the middle part of the first self-expanding member abuts against the upper end of the second strip hole, the limiting rod is rotated and the second self-expanding member slides along the slide groove, thereby pushing out the extension sleeve. The inner wall of the outer tube corresponding to the anchor head is provided with an internal thread for the connecting disc. The self-expanding mechanism is separated from the anchor head, the anchor tube and its connected components are pulled out, and the anchor head and outer tube are left in the anchor hole. Multiple grouting holes are provided on the anchor head and the outer pipe. A grouting machine is used to press mortar into the outer pipe. The mortar inside the outer pipe seeps into the soil layer through the grouting holes and fills the outer pipe, sealing the grouting holes.

2. The combined grouting anchor bolt for tunnels according to claim 1, characterized in that, The side of the threaded sleeve is provided with an ear plate that extends out of the first strip hole, and the second self-expanding member is correspondingly hinged to the ear plate.

3. The combined grouting anchor bolt for tunnels according to claim 1, characterized in that, The inner wall of the outer tube corresponding to one end of the anchor head is provided with an internal thread corresponding to the connecting disc.

4. The combined grouting anchor bolt for tunnels according to claim 1, characterized in that, The limiting rod passes through the connecting plate and has baffles on both sides of the connecting plate to form a rotatable connection with the connecting plate.

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