A new type of extrusion and expansion grouting non-overflow anchor structure and anchoring method

Abstract

The present invention relates to a novel extrusion-expansion grouting non-overflowing anchor rod structure, comprising a drill hole, an anchor rod body, a grouting bag, a tray and a nut, wherein the internal cavity of the anchor rod body is a through hole; the upper end of the anchor rod body is an expansion section, an overflow notch is provided on the expansion section, and the internal cavity of the expansion section is a conical reducing hole; at least one spherical ball is slidably connected in the through hole; the spherical ball squeezes the reducing hole to force the overflow notch to bend and expand to connect the through hole, and the spherical ball squeezes the reducing hole to force the expansion section to bend and expand to both sides and tightly against the inner wall of the drill hole; a water-permeable but grout-proof grouting bag is tied outside the anchor rod body, the anchor rod body together with the grouting bag is placed in the drill hole, and the lower end of the anchor rod body extends out of the drill hole to connect the tray and the nut. The present invention also relates to an anchoring method for a novel extrusion-expansion grouting non-overflowing anchor rod structure. The present invention belongs to a full-length anchoring anchor rod that quickly applies preload, which solves the problem of difficult anchoring in water-rich fractured surrounding rock and has good promotion value.

Description

Technical Field

[0001] The invention relates to the technical field of anchor rod support, and in particular to a novel extrusion and expansion type grouting non-overflowing anchor rod structure and an anchoring method. Background Art

[0002] Conventional anchor rods use resin rolls as anchoring agents, and preload can be applied for a certain period of time after anchoring. However, if a water-rich fissure is developed in an area, the fissure water will flow out along the borehole after drilling, and the commonly used resin anchor will weaken its anchoring strength or even fail after coming into contact with water.

[0003] For broken surrounding rock, it is difficult for conventional resin-coated anchors to achieve an ideal anchoring effect. If traditional grouting anchors are used to grout the borehole, the slurry will overflow into the tunnel along the cracks or flow into the deep cracks. The grouting pressure cannot reach the preset pressure, and the ideal slurry-filled and pressurized state cannot be achieved in the borehole, which not only wastes the slurry, but also makes it difficult to clean up the slurry that flows into the tunnel.

[0004] Therefore, such problems always restrict the speed and effect of rapid installation and anchoring of anchor rods in water-rich surrounding rock sections, fracture-developed tunnels, soft rock tunnels, coal seam tunnels, etc. in coal mines, thus affecting the safety and normal use of the tunnel surrounding rock.

[0005] Authorization announcement No. CN205189918U discloses an expandable hollow grouting anchor rod. By adjusting the adjusting nut, the extrusion tube is moved along the anchor rod body toward the expansion section of the expansion tube, so that the expansion section of the expansion tube expands radially and presses against the surrounding rock wall of the anchor rod hole. After grouting, the slurry penetrates into the surrounding rock around the hole wall to achieve full-length anchoring of the anchor rod. It also describes placing an appropriate amount of explosives at the bottom of the anchor rod hole for bottom blasting to form an enlarged hole to enhance the grouting effect and enhance the anchoring force of the anchor rod end.

[0006] Although the above-mentioned patent documents can achieve good anchoring effects, their overall anchoring structure is complex. The anchor rod body adopts a multi-section assembly structure, and an extrusion tube, an adjustment nut, and an expansion tube are installed outside the anchor rod body to realize the expansion function, which makes it impossible to achieve rapid installation of the anchor rod. At the same time, the entire anchoring construction process is cumbersome to operate, and the slurry penetrates into the surrounding rock around the hole wall, and cannot be applied to anchoring in areas with developed fractured surrounding rocks and water-rich areas, and it is also impossible to achieve the expected effects of slurry pressure maintenance and slurry non-overflow. Summary of the invention

[0007] In order to solve the problem that existing anchor support structures and processes cannot achieve effective anchoring of water-rich fissured surrounding rocks, the present invention provides a new type of extrusion expansion grouting non-overflow anchor structure and anchoring method, which can not only effectively ensure the rapid installation of the anchor, but also achieve full-length anchoring effect, solving the difficult problems of difficult support of soft rock, difficult support of broken surrounding rock, difficult construction of water flowing tunnels in holes, and difficult anchoring in water-rich areas.

[0008] To achieve the above purpose, the technical solution adopted by the present invention is:

[0009] A novel extrusion-expansion grouting non-overflow anchor structure comprises a drill hole, an anchor body, a grouting bag, a tray and a nut, wherein the anchor body is a hollow cylinder, and the inner cavity of the anchor body is a through hole;

[0010] The upper end of the anchor body is an expansion section, which has the function of bending and expanding outwards. An overflow notch is provided on the expansion section. The internal cavity of the expansion section is a conical diameter-reducing hole to connect with the overflow notch. The small diameter end of the diameter-reducing hole is located on the upper end surface of the expansion section, and the diameter of the small diameter end is smaller than the diameter of the through hole.

[0011] At least one spherical ball is slidably connected in the through hole to control the connection and disconnection of the through hole and the variable diameter hole;

[0012] The spherical ball extrusion reducing hole forces the overflow notch to bend and expand into a "V" shape to connect with the through hole, and the spherical ball extrusion reducing hole forces the expansion section to bend and expand to both sides into an inverted cone shape to press against the inner wall of the drill hole, thereby achieving end anchoring;

[0013] The anchor rod body is tied with the water-permeable and slurry-proof cladding bag outside, the anchor rod body and the cladding bag are placed in the drilled hole, and the lower end of the anchor rod body extends out of the drilled hole to connect the tray and the nut.

[0014] Furthermore, the overflow notch has a rectangular cross section and radially penetrates the expansion section. The overflow notch cuts into the expansion section axially to separate the expansion section into two symmetrical sides. After the expansion section on each side and the reducing hole are connected and combined, the cross section is fan-shaped.

[0015] Furthermore, the diameter of the small diameter end of the reducing hole is d1, the diameter of the large diameter end of the reducing hole is d2, the diameter of the through hole is d3, and the diameter of the spherical ball is d4, wherein d1 is less than d4, d2 is equal to d3 and equal to d4.

[0016] Furthermore, the length of the variable diameter hole is H, the number of the spherical balls is 1, 2, 3 or N, and the superimposed length of the N spherical balls is less than H, otherwise the last spherical ball cannot squeeze through the overflow notch to achieve slurry overflow.

[0017] Furthermore, the cladding bag is made of a nylon woven bag, a polyethylene bag or a fiber bag, or can be made of other bags that are water-permeable but impermeable to slurry. The cladding bag is sleeved over the anchor body, with the opening end of the cladding bag close to the lower end of the anchor body. A bag tying rope is provided at the open end of the cladding bag to tie the cladding bag to the anchor body.

[0018] A novel anchoring method of an extrusion-expansion grouting non-overflowing anchor bolt structure, based on the novel extrusion-expansion grouting non-overflowing anchor bolt structure, comprises the following steps:

[0019] Step 1: Making the anchor body: Select an anchor body of appropriate length according to the length of the drilled hole, and then prepare a spherical ball that matches the diameter of the through hole;

[0020] Step 2: Put the anchor body into the drill hole: first, put the grout bag into the anchor body, tie the open end of the grout bag to the anchor body with the bag tying rope, and put them into the bottom of the drill hole, then put the spherical ball into the anchor body, and connect the lower end of the anchor body to the grouting pipeline;

[0021] Step 3, grouting: start the grouting equipment, inject slurry into the anchor body, the slurry pushes the spherical ball to move along the through hole to the variable diameter hole, and after reaching the variable diameter hole, the high-pressure slurry pushes the spherical ball to continue moving to initially rupture the variable diameter hole;

[0022] The slurry is continuously injected, and multiple spherical balls continuously enter the variable diameter hole, and the variable diameter hole is expanded and cracked again, until all the spherical balls enter the variable diameter hole to achieve complete expansion and cracking of the variable diameter hole. At this time, the expansion section expands into an inverted cone and presses against the inner wall of the drill hole;

[0023] At the same time, the through hole is connected with the overflow notch, and the slurry is quickly injected into the cladding bag through the overflow notch until the cladding bag is completely filled. The cladding bag expands and fills the drilled hole. The cladding bag is used to wrap the slurry, so that the slurry does not overflow, reducing the amount of injected slurry.

[0024] Step 4: Install the tray and nut, and apply pre-tightening force to the anchor body to complete the entire anchoring operation, which can play a good role in supporting water-rich fractured surrounding rocks.

[0025] Furthermore, in step 1, the manufacturing process of the anchor body includes the processing of the through hole, the reducing hole and the overflow notch.

[0026] Furthermore, in step 3, under the driving force of the high-pressure slurry, the spherical ball slowly enters until it is completely in the variable diameter hole. During this process, the expansion section gradually expands into an inverted cone, and the overflow notch gradually expands into a "V" shape.

[0027] Through the above technical solution, the beneficial effects of the present invention are:

[0028] The anchoring installation process of the present invention firstly puts the grouting bag on the hollow anchor body, and injects grout into the lower end of the anchor body. As the grouting slurry is sent into the through hole, the spherical ball will cause the expansion section to expand and crack, and after the expansion and cracking, it will lock the surrounding rock hole wall and apply a preload. The grouting slurry will enter the variable diameter hole along the through hole, and be poured into the grouting bag under high pressure. The excess water and air in the slurry will seep out through the water-permeable and non-grout-permeable grouting bag, which belongs to "active support + full-field anchoring". The whole anchoring process method is convenient, easy to construct, safe and reliable, and cost-effective. It can also provide a greater tunnel surrounding rock support strength, and well solves the problems of difficult support of soft rock, difficult support of broken surrounding rock, difficult construction of water-flowing tunnels in the hole, and difficult anchoring in water-rich areas. It can meet the multiple mining influences of advance support pressure and post-mining peak pressure and the requirements of controlling deformation of tunnel surrounding rocks.

[0029] The anchor body of the present invention is an integrated anchor, does not need to be installed in steps, has strong pre-tightening force, can solve the current situation that traditional anchoring agents have poor anchoring effect and cannot quickly provide initial supporting force, and can immediately provide initial supporting force through the expansion and cracking of the expansion section after installation, which is convenient and reliable; combined with full-length grouting anchoring, it is incomparable to traditional full-length anchoring and end-anchor anchoring, and is a full-length anchoring anchor that quickly applies pre-tightening force, which increases the anchoring performance of the anchor body as a whole, realizes the maximum contact between the anchor body and the surrounding rock, and can be used for rapid support of surrounding rock tunnels in complex geological conditions such as water-rich areas, broken areas, and mining affected areas, and has good promotion value and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of a new type of extrusion and expansion type grouting non-overflowing anchor rod structure of the present invention.

[0031] Figure 2 The present invention Figure 1 Schematic diagram of the upper end of the middle anchor rod body.

[0032] Figure 3 The present invention Figure 1 Schematic diagram of the lower end of the middle anchor rod body.

[0033] Figure 4 It is a schematic diagram of the un-expanded state of the expanded section of a novel extrusion-expanding grouting non-overflowing anchor rod structure of the present invention.

[0034] Figure 5 It is a schematic diagram of the expansion section of a novel extrusion expansion type grouting non-overflow anchor structure of the present invention after expansion and expansion, and the G arrow in the figure indicates the outflow direction of the slurry through the overflow port.

[0035] Figure 6It is a schematic diagram of the movement of a spherical ball in a through hole of an anchoring method of a novel extrusion and expansion grouting non-overflowing anchor rod structure of the present invention. In the figure, diagram A indicates that the slurry initially pushes the spherical ball upward, and diagram B indicates that the slurry continues to push the spherical ball upward to approach the variable diameter hole.

[0036] Figure 7 It is a schematic diagram of the movement of a spherical ball in a variable diameter hole in an anchoring method of a novel extrusion and expansion grouting non-overflowing anchor rod structure of the present invention. In the figure, diagram C shows the spherical ball initially squeezing the variable diameter hole, diagram D shows the spherical ball squeezing the variable diameter hole again, and diagram E shows the spherical ball completely squeezing the variable diameter hole.

[0037] The numbers in the attached figure are: 1 drill hole, 2 anchor body, 3 grout bag, 4 tray, 5 nut, 6 through hole, 7 expansion section, 8 overflow notch, 9 reducing hole, 10 spherical ball, 11 bag tying rope, 12 overflow port. DETAILED DESCRIPTION

[0038] The specific implementation of the present invention is described in detail below with reference to the accompanying drawings:

[0039] like Figure 1~Figure 5 As shown, a novel extrusion expansion type grouting non-overflow anchor structure includes a drill hole 1, an anchor body 2, a grout bag 3, a tray 4 and a nut 5. The anchor body 2 is a hollow cylinder, the inner cavity of the anchor body 2 is a through hole 6, the diameter of the through hole 6 is d3, and the through hole 6 is also a grouting hole, which can be used as a flow channel for the slurry.

[0040] The upper end of the anchor body 2 is an expansion section 7, which can achieve the outer diameter expansion of the upper end of the anchor body 2 under the push of a certain force. An overflow notch 8 is provided on the expansion section 7, and the cross section of the overflow notch 8 is rectangular. The overflow notch 8 radially penetrates the expansion section 7, and the overflow notch 8 cuts into the expansion section 7 axially, thereby dividing the expansion section 7 into two symmetrical sides.

[0041] The internal cavity of the expansion section 7 is a tapered diameter reducing hole 9. The cross section of each side expansion section 7 and the diameter reducing hole 9 is fan-shaped after being connected and combined. The diameter reducing hole 9 is connected to the overflow notch 8, and the overflow notch 8 divides the diameter reducing hole 9 into two semi-conical structures.

[0042] The length of the variable diameter hole 9 is H, and the two ends of the variable diameter hole 9 are respectively a large diameter end and a small diameter end, wherein the diameter of the small diameter end of the variable diameter hole 9 is d1, the small diameter end is located on the upper end surface of the expansion section 7, and the diameter d1 of the small diameter end is smaller than the diameter d3 of the through hole 6. The diameter of the large diameter end of the variable diameter hole 9 is d2, and d2 is equal to the diameter d3 of the through hole 6.

[0043] At least one spherical ball 10 is slidably connected in the through hole 6 . The diameter of the spherical ball 10 is d4 , which is equal to the diameter d3 of the through hole 6 . Thus, the spherical ball 10 can roll freely in the through hole 6 .

[0044] The number of spherical balls 10 can be 1, 2, 3 or N, and the superimposed length of N spherical balls 10 is less than the length H of the reducing hole 9. The purpose is to ensure that all spherical balls 10 are placed in the reducing hole 9 to achieve communication between the through hole 6 and the overflow notch 8.

[0045] In this embodiment, there are three spherical balls 10, which are in contact with each other without any gaps. The connection and disconnection of the through hole 6 and the variable diameter hole 9 can be controlled by the different rolling positions of the spherical balls 10, that is, when the spherical ball 10 is placed in the through hole 6, the through hole 6 and the variable diameter hole 9 are not connected. When the spherical ball 10 is placed in the variable diameter hole 9, the through hole 6 and the variable diameter hole 9 are connected.

[0046] Under the driving force of the slurry, the spherical ball 10 squeezes the reducing hole 9 and forces the overflow notch 8 to bend and expand into a "V" shape, thereby connecting the through hole 6; at the same time, the spherical ball 10 squeezes the reducing hole 9 and forces the expansion section 7 to bend and expand to both sides into an inverted cone shape and tightly against the inner wall of the drilled hole 1.

[0047] A water-permeable but grout-proof cladding bag 3 is tied outside the anchor body 2. The cladding bag 3 can be made of a nylon woven bag, a polyethylene bag or a fiber bag, but is not limited thereto. It can also be made of other bags with water-permeable but grout-proof functions.

[0048] When installing, the cladding bag 3 is sleeved outside the anchor body 2, the opening end of the cladding bag 3 is close to the lower end of the anchor body 2, and a bag tying rope 11 is provided at the opening end of the cladding bag 3 to tie the cladding bag 3 to the anchor body 2. The anchor body 2 together with the cladding bag 3 is placed in the drilled hole 1, and the lower end of the anchor body 2 extends out of the drilled hole 1 to connect the tray 4 and the nut 5.

[0049] like Figure 6~Figure 7 As shown, a novel method for anchoring a new type of extrusion-expansion grouting anchor structure without overflowing grouting comprises the following steps:

[0050] Step 1, production of the anchor body 2: Select an anchor body 2 of appropriate length according to the length requirement of the drill hole 1 for production and processing, wherein the production and processing of the anchor body 2 includes processing of the through hole 6, the reducing hole 9 and the overflow notch 8; and then prepare a spherical ball 10 that matches the diameter of the through hole 6.

[0051] Step 2, the anchor body 2 is sent into the drilled hole 1: first, the grout bag 3 is put into the anchor body 2, and the open end of the grout bag 3 is tied to the anchor body 2 with the bag tying rope 11, and sent to the bottom of the drilled hole 1; before grouting, the spherical ball 10 is placed in the anchor body 2, and the lower end of the anchor body 2 is connected to the grouting pipeline.

[0052] Step 3, grouting: start the grouting equipment, inject the slurry into the anchor body 2 through the grouting pipeline, and the high-pressure slurry pushes the spherical ball 10 to move along the through hole 6 to the variable diameter hole 9. After reaching the variable diameter hole 9, the high-pressure slurry pushes the spherical ball 10 to continue moving to initially rupture the variable diameter hole 9;

[0053] The high-pressure slurry is continuously injected, and multiple spherical balls 10 enter the variable hole 9 in turn, and the variable hole 9 is expanded again until all the spherical balls 10 enter the variable hole 9 to achieve complete expansion of the variable hole 9; at this time, the expansion section 7 expands into an inverted cone and presses against the inner wall of the drilled hole 1, generating prestress and playing an anchoring role.

[0054] Under the driving force of the high-pressure slurry, the spherical ball 10 slowly enters until it is completely in the variable diameter hole 9. During the entire expansion process of the variable diameter hole 9, the expansion section 7 gradually expands into an inverted cone, and the overflow notch 8 gradually expands into a "V" shape.

[0055] At the same time, the through hole 6 is connected with the lower end of the overflow notch 8, that is, the lower end of the overflow notch 8 is the overflow port 12, and the overflow port 12 only occupies a small part of the overflow notch 8. The slurry is quickly injected into the grouting bag 3 through the overflow port 12. Since the grouting bag 3 is bound by the bag tying rope 11 and has the function of water permeability but not grouting, the slurry will not overflow out of the borehole 1 along the surrounding rock cracks and cannot effectively apply sufficient grouting pressure. As the injected slurry completely fills the grouting bag 3, the grouting bag 3 expands and tightly fills the borehole 1. Since the expansion section 7 tightly squeezes the wall of the borehole 1, the dual effects of rapid end pre-tightening and full-length anchoring of the anchor rod are achieved at this time.

[0056] Step 4, install the tray 4 and the nut 5, and apply pre-tightening force to the anchor body 2 to complete the entire anchoring operation, which can solve the problem of overflow and failure to retain grout after conventional anchor grouting in water-rich fractured surrounding rock drilling holes, and inability to quickly install the nut 5 and tray 4.

[0057] The embodiments described above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, any equivalent changes or modifications made according to the structures, features and principles described in the patent scope of the present invention should be included in the scope of the patent application of the present invention.

Claims

1. An extrusion-expansion grouting non-overflow anchor structure, comprising a drill hole (1), an anchor body (2), a grout bag (3), a tray (4) and a nut (5), It is characterized in that The anchor rod body (2) is a hollow cylinder, and the internal cavity of the anchor rod body (2) is a through hole (6); The upper end of the anchor rod body (2) is an expansion section (7), an overflow notch (8) is provided on the expansion section (7), the internal cavity of the expansion section (7) is a tapered diameter reducing hole (9) connected to the overflow notch (8), the small diameter end of the tapered diameter reducing hole (9) is located on the upper end surface of the expansion section (7), and the diameter of the small diameter end is smaller than the diameter of the through hole (6); The overflow notch (8) has a rectangular cross section and radially penetrates the expansion section (7). The overflow notch (8) is cut into the expansion section (7) axially to separate the expansion section (7) into two symmetrical sides. The expansion section (7) on each side and the tapered diameter reducing hole (9) are connected and assembled to form a fan-shaped cross section. At least one spherical ball (10) is slidably connected in the through hole (6) to control the opening and closing of the through hole (6) and the tapered reducing hole (9); the diameter of the tapered reducing hole (9) at the small diameter end is d1, the diameter of the tapered reducing hole (9) at the large diameter end is d2, the diameter of the through hole (6) is d3, and the diameter of the spherical ball (10) is d4, wherein d1 is less than d4, d2 is equal to d3 and equal to d4; The spherical ball (10) squeezes the tapered reducing hole (9) to force the overflow notch (8) to bend and expand into a "V" shape to connect with the through hole (6); the spherical ball (10) squeezes the tapered reducing hole (9) to force the expansion section (7) to bend and expand to both sides into an inverted cone shape and tightly abut against the inner wall of the drill hole (1); The anchor rod body (2) is tied with a water-permeable but non-permeable grout bag (3) outside the anchor rod body (2). The anchor rod body (2) and the grout bag (3) are placed in the drilled hole (1). The lower end of the anchor rod body (2) extends out of the drilled hole (1) to connect with the tray (4) and the nut (5).

2. According to claim 1, a squeeze-expansion grouting non-overflow anchor structure, It is characterized in that The tapered reducing hole (9) has a length of H, the number of the spherical balls (10) is 1, 2, 3 or N, and the superimposed length of the N spherical balls (10) is less than H.

3. According to claim 1, a squeeze-fracture grouting non-overflow anchor structure, It is characterized in that The cladding bag (3) is made of a nylon woven bag, a polyethylene bag or a fiber bag. The cladding bag (3) is sleeved outside the anchor body (2). The opening end of the cladding bag (3) is close to the lower end of the anchor body (2). A bag tying rope (11) is provided at the opening end of the cladding bag (3) to tie the cladding bag (3) to the anchor body (2).

4. An anchoring method for an extrusion-fracture grouting anchor rod structure without overflowing grout, It is characterized in that An extrusion-expansion grouting non-overflow anchor structure according to any one of claims 1 to 3 comprises the following steps: Step 1, manufacturing the anchor body (2): selecting an anchor body (2) of suitable length according to the length requirement of the drill hole (1) for manufacturing and processing, and then preparing a spherical ball (10) that matches the diameter of the through hole (6); Step 2, inserting the anchor body (2) into the drilled hole (1): first, insert the grout bag (3) into the anchor body (2), use the bag tying rope (11) to tie the open end of the grout bag (3) to the anchor body (2), and then insert the grout bag (3) into the bottom of the drilled hole (1), and then put the spherical ball (10) into the anchor body (2), and connect the lower end of the anchor body (2) to the grouting pipeline; Step 3, grouting: starting the grouting equipment, injecting slurry into the anchor body (2), the slurry pushing the spherical ball (10) to move along the through hole (6) to the tapered reducing hole (9), after reaching the tapered reducing hole (9), the high-pressure slurry pushes the spherical ball (10) to continue moving to initially rupture the tapered reducing hole (9); The slurry is continuously injected, and a plurality of spherical balls (10) continuously enter the tapered reducing hole (9), causing the tapered reducing hole (9) to be expanded again, until all the spherical balls (10) enter the tapered reducing hole (9) to achieve complete expansion of the tapered reducing hole (9), at which time the expansion section (7) expands into an inverted cone and is tightly pressed against the inner wall of the drill hole (1); At the same time, the through hole (6) is connected to the overflow notch (8), and the slurry is quickly injected into the slurry bag (3) through the overflow notch (8) until the slurry bag (3) is completely filled, and the slurry bag (3) expands and fills the drilled hole (1); Step 4: Install the tray (4) and the nut (5), and apply a pre-tightening force to the anchor rod body (2) to complete the entire anchoring operation.

5. An anchoring method for an extrusion-expansion grouting non-overflowing anchor structure according to claim 4, It is characterized in that In step 1, the manufacturing process of the anchor rod body (2) includes the processing of the through hole (6), the tapered diameter reducing hole (9) and the overflow notch (8).

6. The anchoring method of the extrusion-expansion grouting non-overflow anchor structure according to claim 4, It is characterized in that In step 3, under the driving force of the high-pressure slurry, the spherical ball (10) slowly enters until it is completely located in the tapered reducing hole (9). During this process, the expansion section (7) gradually expands into an inverted cone, and the overflow notch (8) gradually expands into a "V" shape.

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