Solid anchor cable double-section step-by-step pumping prestress full-length anchoring device and method

Abstract

The invention belongs to the technical field of coal mine tunnel supporting, and discloses a solid anchor cable double-section step-by-step pumping prestress full-length anchoring device and method.The solid anchor cable double-section step-by-step pumping prestress full-length anchoring device comprises an anchoring rod mechanism, an anchoring head is arranged at the bottom of the anchoring rod mechanism, end tensioning thorns are evenly distributed on the outer wall of the anchoring head, and a connecting mechanism is arranged at the top of the anchoring rod mechanism; an inner buckling cavity is formed in the connecting mechanism, the problems that in the prior art, construction is complex, cost is high, and the anchoring effect is unstable are solved, the solid anchor cable is combined with the simplified grouting device, and the effect that the anchor cable exerts prestress is achieved. Compared with the prior art, the scheme has the technical advantages of being easy to operate, high in anchoring quality, low in cost and high in construction efficiency, the safety and reliability of coal mine roadway supporting are effectively improved, the problem that anchoring holes are generated due to uneven grouting during grouting is solved, and the method is suitable for roadway supporting engineering under various complex geological conditions.

Description

Technical Field

[0001] The present application relates to the technical field of coal mine tunnel support, and more specifically, to a solid anchor cable double-section step-by-step pumping prestressed full-length anchoring device and method. Background Art

[0002] In the field of coal mine tunnel support, anchor cables, as an important supporting component, are widely used to control the deformation of tunnel surrounding rocks and improve their stability. In order to improve the supporting effect of anchor cables, prestressed full-length anchoring technology has gradually been applied to the installation of anchor cables, aiming to achieve full-length bonding of anchor cables and apply prestress, further improve the supporting performance of anchor cables, and extend the service life of tunnels. At present, there are two main technical paths for prestressed full-length anchoring of anchor cables:

[0003] (1) Prestressed full-length anchoring is achieved by increasing the number of resin anchor rolls. This technical approach is to achieve full-length anchoring of the anchor cable by increasing the number of anchor rolls in the borehole. Specifically, by placing fast-, medium- and slow-curing resin anchor rolls in the borehole in sequence, segmented anchoring of the anchor cable is achieved at different curing speeds, followed by tensioning and pre-tightening. However, this method has some shortcomings, such as a large number of rolls, difficulty in mixing, and complex operation. In actual construction, it is easily affected by the construction quality of workers, resulting in unstable anchoring effect.

[0004] (2) Use hollow grouting anchors in combination with resin anchors to achieve prestressed full-length anchoring of anchors. First, place a resin roll at the end of the borehole, and stir the anchor to anchor the end of the anchor. Then, tension the anchor and pre-tighten it. Use the hollow grouting anchor to inject grouting material so that the anchor forms a full-length bond with the surrounding coal and rock mass, thereby achieving the effect of prestressed full-length anchoring. This method improves the shortcomings of using traditional resin rolls to achieve full-length anchoring to a certain extent, but its implementation process is relatively complicated and requires a dedicated hollow grouting anchor. It also does not completely get rid of the problem of poor mixing of resin anchors, which leads to anchoring voids. At the same time, the construction cost is relatively high. In addition, due to the hollow structure design of the anchor, the strength of the hollow anchor is lower than that of the solid anchor under the same material and the same outer diameter, which may lead to limitations in the anchoring effect.

[0005] In summary, although the existing technology can achieve full-length prestressed anchoring of anchor cables to a certain extent, there are still problems such as complex construction, high cost and unstable anchoring effect. Therefore, there is an urgent need for a simpler, more effective and more stable full-length prestressed anchoring method for solid anchor cables to improve the safety and reliability of coal mine tunnel support. In order to solve the above problems, the present application provides a solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device and method. Summary of the invention

[0006] The present application provides a solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device and method using the following technical solutions:

[0007] A solid anchor cable two-stage step-by-step pumping prestressed full-length anchoring device and method, including an anchor rod mechanism, an anchor head is provided at the bottom of the anchor rod mechanism, and evenly distributed end tensioning spikes are provided on the outer wall of the anchor head. A connecting mechanism is provided at the top of the anchor rod mechanism, and an inner buckle cavity is opened in the connecting mechanism. Evenly distributed steel strands are arranged around the outer wall of the anchor rod mechanism, and the upper and lower outer walls of the steel strands are fixed to the outer wall of the anchor rod mechanism by steel hoops, and a pressure relief valve is provided at the end of the anchor mechanism.

[0008] Furthermore, the anchor head is conical in shape, the end tensioning barbs are of the same shape and decrease in volume in a descending order, and the anchor rod mechanism and the anchor head are integrally cast.

[0009] Furthermore, the anchor rod mechanism includes an anchor rod, a surrounding pipe groove is provided on the outer wall of the anchor rod, the outer wall of the anchor rod is provided with rod tensioning thorns spirally distributed between the pipe grooves, the rod tensioning thorns are each provided with a tensioning groove, the pipe groove is provided with evenly distributed mounting buckles, the mounting buckles are provided with a grouting pipe, the grouting pipe is penetrated by evenly distributed injection holes on the side away from the mounting buckle, and the injection holes are each provided with a cross coating.

[0010] Furthermore, the grouting pipe is clamped on the installation buckle, and the grouting pipe is fixed in the pipe groove along the pipe groove path through the installation buckle.

[0011] Furthermore, the injection holes are evenly distributed on the outer wall of the grouting pipe in a row of three, the number of cross coatings in each injection hole is four, and the gaps between the cross coatings are cross-shaped, and the cross coatings are connected to each other by rubber coatings.

[0012] Furthermore, the connecting mechanism includes an installation groove, an annular locking block is opened in the installation groove, locking blocks are penetrated on both sides of the inner wall of the installation groove, blocks are provided on one side of the locking blocks, reset rods are provided at the four corners of the side of the block away from the rotating groove, an installation block is provided in the installation groove, rotating rings are provided in the middle parts of the arcuate edges on both sides of the installation block, an anchor cable fixing platform is provided on the top of the installation block, and evenly distributed anchor cable hooks are provided on the top of the anchor cable fixing platform.

[0013] Furthermore, the installation plug block is located in the installation groove, the rotating ring slides in the rotating groove, and the stop block and the locking stop block are embedded in the outer wall of the installation groove.

[0014] Furthermore, the anchoring method includes: firstly drilling a hole in the coal rock mass, assembling an anchor rod mechanism according to the drilling depth, then placing the anchor device in the borehole, achieving extrusion friction with the end hole wall of the borehole through the tensioning bar on the anchor head, injecting anchoring agent into the grouting pipe after connecting the grouting pipe through the grouting pump, releasing the pressure through the pressure relief valve, releasing the air in the grouting pipe in advance, and calculating the flow rate and injection time. After the anchoring agent enters the end of the grouting pipe, increasing the pressure injected by the grouting pump to increase the internal pressure of the grouting pipe. Since the released pressure is less than the injected pressure, the cross coating is broken from the inside of the borehole to the outside and the anchoring agent flows out, so that the internal injection is uniform, then disconnecting the grouting pump and the grouting pipe, and then installing the connecting mechanism to complete the first stage of end anchor anchoring, then installing the anchor cable supporting tray lock, applying prestress tension and pre-tightening, and finally connecting the grouting pump to the grouting pipe again, and performing secondary grouting according to the amount of slurry required for bonding the remaining anchor cable segment until the full length of the anchor cable is anchored. .

[0015] In summary, this application includes the following beneficial technical effects:

[0016] The problems of complex construction, high cost and unstable anchoring effect in the prior art are solved by using solid anchor cables combined with simplified grouting devices to achieve the effect of prestressing the anchor cables. Compared with the prior art, the solution of the present invention has the advantages of simple operation, high anchoring quality, low cost and high construction efficiency, effectively improving the safety and reliability of coal mine tunnel support, reducing the effect of anchoring voids caused by uneven grouting during grouting, and being suitable for tunnel support projects under various complex geological conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of this application;

[0018] Figure 2 This is a schematic diagram of the connection mechanism structure of this application;

[0019] Figure 3 This is a schematic diagram of the structure of the anchor rod mechanism of the present application;

[0020] Figure 4 For this application Figure 2 The enlarged structural diagram at A in the middle;

[0021] Figure 5 For this application Figure 2 The enlarged structural diagram at B in the middle;

[0022] Figure 6 For this application Figure 3 The enlarged structural diagram at C in the middle;

[0023] Figure 7 This is a schematic diagram of the block structure of this application;

[0024] Figure 8 This is a schematic diagram of the anchor cable fixing platform structure of this application;

[0025] Fig. 9 This is a schematic diagram of the cross-laminated structure of the present application.

[0026] Description of the numbers in the figure:

[0027] 1. Anchor rod mechanism; 101. Anchor rod; 102. Pipe groove; 103. Grouting pipe; 104. Injection hole; 105. Rod tensioning thorn; 106. Tensioning groove; 107. Mounting buckle; 108. Cross coating; 2. Anchor head; 3. End tensioning thorn; 4. Connecting mechanism; 401. Mounting groove; 402. Locking block; 403. Rotating groove; 404. Block; 405. Reset rod; 406. Anchor cable fixing platform; 407. Mounting plug; 408. Rotating ring; 409. Anchor cable hook; 5. Inner buckle cavity; 6. Steel strand; 7. Pressure relief valve. DETAILED DESCRIPTION

[0028] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0029] Example:

[0030] The present application discloses a solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device and method, please refer to Figure 1-Figure 9, including an anchor rod mechanism 1, an anchor head 2 is provided at the bottom of the anchor rod mechanism 1, and evenly distributed end tensioning thorns 3 are provided on the outer wall of the anchor head 2. A connecting mechanism 4 is provided at the top of the anchor rod mechanism 1, and an inner buckle cavity 5 is opened in the connecting mechanism 4. Evenly distributed steel strands 6 are arranged around the outer wall of the anchor rod mechanism 1, and the upper and lower outer walls of the steel strands 6 are fixed to the outer wall of the anchor rod mechanism 1 through steel hoops. A pressure relief valve 7 is provided at the end of the anchor mechanism 1. The anchor head 2 is conical in shape, and the end tensioning thorns 3 have the same shape and decrease in volume successively. The anchor rod mechanism 1 and the anchor head 2 are made of integral casting. The anchor rod mechanism 1 serves as the main structure of the entire anchoring device. The anchor rod mechanism not only bears the key task of transmitting prestress, but also ensures the structural integrity and stability during the anchoring process. Its design takes into account the dual needs of material mechanics and mine pressure, ensuring its applicability under different geological conditions. The anchor head 2 is located at the bottom of the anchor rod mechanism and adopts a conical design. This shape is not only conducive to the smooth insertion of the anchor cable in the coal rock mass, but also provides greater friction when applying prestress, thereby enhancing the anchoring effect. More uniquely, the end tensioning thorns 3 are evenly distributed on the outer wall of the anchor head. These thorn-like structures have the same shape but the volume decreases successively. They can gradually penetrate the medium during the insertion process to form a tighter connection body, and effectively prevent the loosening and falling of the anchor cable in the vertical drilling due to gravity. The anchor rod mechanism 1 and the anchor head 2 are made of one-piece casting. This manufacturing process not only simplifies the production process and improves production efficiency, but more importantly, it ensures seamless connection between the two, avoiding stress concentration or failure caused by poor connection, thereby further improving the overall strength and durability of the anchoring device. The connection mechanism 4: The connection mechanism located at the top of the anchor rod mechanism is the key node for prestress application and transmission. It is designed with an inner buckle cavity 5, which provides a convenient channel for applying prestress to the anchor cable and also facilitates reliable connection with the upper structure.

[0031] The anchor rod mechanism 1 includes an anchor rod 101, a surrounding pipe groove 102 is provided on the outer wall of the anchor rod 101, a rod tensioning thorn 105 is spirally distributed between the pipe grooves 102, and a tensioning groove 106 is provided in the rod tensioning thorn 105. The pipe groove 102 is provided with evenly distributed mounting buckles 107, and a grouting pipe 103 is provided on the mounting buckle 107. The side of the grouting pipe 103 away from the mounting buckle 107 is penetrated with evenly distributed injection holes 104, and the injection holes 104 are provided with a cross coating 108. The grouting pipe 103 is clamped on the mounting buckle 107, and the grouting pipe 103 is fixed in the pipe groove 102 along the path of the pipe groove 102 through the mounting buckle 107. The injection holes 104 are evenly distributed in the grouting pipe 103 in a row of three. 03's outer wall, there are four cross coatings 108 in each injection hole 104, and the gaps between the cross coatings 108 are cross-shaped, and the cross coatings 108 are connected to each other by rubber coatings. The anchor rod 101 is the main body for bearing prestress and transmitting anchoring force. The anchor rod 101 is made of high-strength material to ensure stability and durability in extreme environments. The pipe groove 102 opened along the outer wall of the anchor rod 101 not only provides a channel for subsequent medium injection, but also enhances the surface area of ​​the anchor rod 101, which is conducive to forming a closer contact and anchoring with the surrounding medium. The rod tensioning thorns 105 are spirally distributed between the rod tensioning thorns 105 between the pipe grooves 102, which is a key design to enhance the anchoring effect. These tensioning thorns can penetrate the surrounding medium during the anchoring process to form a mechanical lock, effectively preventing the loosening and pulling out of the anchor cable. The tensioning groove 106 is provided in the tensioning thorn 105 of the rod, which may be used to further optimize the mechanical properties of the tensioning thorn, such as improving the shear strength or promoting the penetration of the medium. The installation buckles 107 are evenly distributed in the pipe groove 102, providing a reliable support point for the fixation of the grouting pipe 103. Through the installation buckles 107, the grouting pipe 103 can be stably fixed along the path of the pipe groove 102 to ensure the accuracy and uniformity of the slurry injection. The grouting pipe 103 is the main channel for medium injection. The grouting pipe 103 is installed on the installation buckle 107 by a snap-on method, which is easy to install and disassemble. Its design takes into account the fluidity and injection efficiency of the medium, ensuring that the medium can smoothly enter the surrounding medium and form an effective bond. The injection holes 104 are evenly distributed on the outer wall of the grouting pipe 103. The injection holes 104 are the key to the slurry entering the surrounding medium. The uniform distribution of three injection holes in a row is conducive to the uniform diffusion and penetration of the slurry in the anchoring area. The cross-coating 108 provided in the injection hole 104 plays a role in controlling the slurry release speed and preventing the slurry from leaking in advance. There are four cross-coatings 108 in each injection hole 104, and the gaps between these coatings are arranged in a cross shape, which is conducive to the diffusion and penetration of the slurry in a specific direction.At the same time, the cross coating 108 also has a certain compressive strength and can maintain the integrity of the structure during the slurry injection process. The cross coatings 108 are connected to each other by rubber coatings. This design not only enhances the sealing between the coatings, but also can buffer the impact force generated during slurry injection to a certain extent and protect the surrounding medium from damage.

[0032] The connecting mechanism 4 includes a mounting groove 401, in which an annular locking block 402 is provided, locking blocks 402 are provided on both sides of the inner wall of the mounting groove 401, and a block 404 is provided on one side of the locking block 402, and reset rods 405 are provided on the four corners of the block 404 away from the rotating groove 403, a mounting plug 407 is provided in the mounting groove 401, and a rotating ring 408 is provided in the middle of the arcuate edges on both sides of the mounting plug 407. An anchor cable fixing platform 406 is provided on the top of the installation plug 407, and evenly distributed anchor cable hooks 409 are provided on the top of the anchor cable fixing platform 406. The installation plug 407 is located in the installation groove 401, and the rotating ring 408 slides in the rotating groove 403. The block 404 and the locking block 402 are both embedded in the outer wall of the installation groove 401. The installation groove 401 is the main structure of the connecting mechanism 4, and the installation groove 401 provides a stable installation environment for the installation plug 407. The annular locking block 402 design provided inside it provides key support for the subsequent locking mechanism. The locking block 402 annularly distributed in the installation groove 401 not only enhances the structural strength of the installation groove 401, but also achieves a firm locking of the installation plug 407 through cooperation with the block 404. The design of the locking block 402 penetrating the inner wall of the installation groove 401 allows the locking force to be evenly transmitted to the entire installation groove 401, ensuring the stability of the connection. The block 404 located on the opposite side of the locking block 402 is a key component of the locking mechanism. During the connection process, the block 404 can move with the insertion of the installation plug 407 until it is in close contact with the locking block 402 to achieve a locking effect. The design of the block 404 with reset rods 405 at all four corners not only enhances the stability of the block 404, but also facilitates the operation of the reset rod 405 to restore the block 404 to its original position when the connection mechanism needs to be disassembled, thereby achieving rapid disassembly. The installation plug 407 serves as a bridge connecting the anchor cable and the anchor rod mechanism. The design of the installation plug 407 fully considers the convenience and stability of the connection. The rotating ring 408 disposed in the middle of the arcuate edges on both sides not only facilitates the insertion and rotation adjustment of the installation plug 407, but also realizes the stable sliding and positioning of the installation plug 407 in the installation groove 401 through cooperation with the rotating groove 403. The design of the rotating ring 408 sliding in the rotating groove 403 ensures the smoothness and stability of the installation plug 407 during the insertion process. At the same time, the rotating ring 408 can also provide a certain damping effect when the installation plug 407 is locked to prevent loosening due to external force. The anchor cable fixing platform 406 located at the top of the installation plug 407 provides a spacious and stable plane for the fixing of the anchor cable.Its design takes into account the diversity of anchor cables and the adaptability to different diameters, ensuring that the anchor cables can be firmly fixed on the platform. The anchor cable hooks 409 are evenly distributed on the top of the anchor cable fixing platform 406, providing a reliable fixing point for the anchor cable. The anchor cable hooks 409 can not only adapt to anchor cables of different shapes and specifications, but also can achieve multi-point fixation and balanced force on the anchor cables through mutual cooperation.

[0033] The anchoring method comprises: firstly, drilling a coal rock mass, assembling an anchor rod mechanism 1 according to the drilling depth, then placing the anchor device inside, achieving extrusion friction with the hole wall at the end of the drilling hole through the tensioning barb 3 on the anchor head 2, and connecting the grouting pipe 103 through the grouting pump, injecting anchoring agent into the grouting pipe 103, releasing pressure through the pressure relief valve 7, releasing the air in the grouting pipe 103 in advance, and calculating the flow rate and injection time. After the anchoring agent enters the end of the grouting pipe 103, the pressure injected by the grouting pump is increased. , so that the internal pressure of the grouting pipe 103 increases. Since the leaked pressure is less than the injected pressure, the cross coating 108 is broken from the inside to the outside of the borehole and the anchoring agent flows out, so that the internal injection is uniform. Then the grouting pump and the grouting pipe 103 are disconnected, and then the connecting mechanism 4 is installed to complete the first stage of end anchor anchoring. Then the anchor cable matching tray lock is installed, and prestressing is applied. Finally, the grouting pump is connected to the grouting pipe 103 again, and the secondary grouting is carried out according to the amount of slurry required for bonding the remaining anchor cable segments until the entire length of the anchor cable is anchored.

[0034] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device, comprising an anchor rod mechanism (1), characterized in that: The anchor rod mechanism (1) is provided with an anchor head (2) at the bottom, and the outer wall of the anchor head (2) is provided with evenly distributed end tensioning spikes (3). The top of the anchor rod mechanism (1) is provided with a connecting mechanism (4), and an inner buckle cavity (5) is opened in the connecting mechanism (4). The outer wall of the anchor rod mechanism (1) is surrounded by evenly distributed steel strands (6), and the outer walls of the upper and lower ends of the steel strands (6) are fixed to the outer wall of the anchor rod mechanism (1) by steel hoops. A pressure relief valve (7) is provided at the end of the anchor rod mechanism (1).

2. A solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device according to claim 1, characterized in that: The anchor head (2) is conical in shape, and the end tensioning spikes (3) are of the same shape and decrease in volume in a descending order. The anchor rod mechanism (1) and the anchor head (2) are cast in one piece.

3. The solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device according to claim 1 is characterized by: The anchor rod mechanism (1) comprises an anchor rod (101), the outer wall of the anchor rod (101) is provided with a surrounding pipe groove (102), the outer wall of the anchor rod (101) is provided with rod tensioning spikes (105) which are spirally distributed between the pipe grooves (102), each of the rod tensioning spikes (105) is provided with a tensioning groove (106), the pipe groove (102) is provided with evenly distributed mounting buckles (107), the mounting buckles (107) are provided with a grouting pipe (103), and the grouting pipe (103) is provided with evenly distributed injection holes (104) on a side away from the mounting buckle (107), and each of the injection holes (104) is provided with a cross coating (108).

4. A solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device according to claim 3, characterized in that: The grouting pipe (103) is clamped on the installation buckle (107), and the grouting pipe (103) is fixed in the pipe groove (102) along the path of the pipe groove (102) through the installation buckle (107).

5. A solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device according to claim 4, characterized in that: The injection holes (104) are evenly distributed on the outer wall of the grouting pipe (103) in a row of three, the number of cross-coatings (108) in each injection hole (104) is four, and the gaps between the cross-coatings (108) are cross-shaped, and the cross-coatings (108) are connected to each other by rubber coatings.

6. A solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device according to claim 1, characterized in that: The connecting mechanism (4) comprises a mounting groove (401), an annular locking block (402) is provided in the mounting groove (401), locking blocks (402) are penetrated on both sides of the inner wall of the mounting groove (401), blocks (404) are provided on one side of the locking block (402), reset rods (405) are provided on the four corners of the side of the block (404) away from the rotating groove (403), a mounting plug (407) is provided in the mounting groove (401), rotating rings (408) are provided in the middle of the arcuate edges on both sides of the mounting plug (407), an anchor cable fixing platform (406) is provided on the top of the mounting plug (407), and evenly distributed anchor cable hooks (409) are provided on the top of the anchor cable fixing platform (406).

7. A solid anchor cable double-stage step-by-step pumping prestressed full-length anchoring device according to claim 6, characterized in that: The installation plug block (407) is located in the installation groove (401), the rotating ring (408) slides in the rotating groove (403), and the stop block (404) and the locking stop block (402) are embedded in the outer wall of the installation groove (401).

8. The method for full-length anchoring of a solid anchor cable by two-stage step-by-step pumping of prestressed anchor cables according to claim 1 is characterized in that: The anchoring method comprises: firstly drilling a coal rock mass, assembling an anchor rod mechanism (1) according to the drilling depth, then placing an anchor device inside, achieving extrusion friction with the hole wall at the end of the drilling hole through a tensioning spike (3) on an anchor head (2), connecting a grouting pipe (103) through a grouting pump, injecting an anchoring agent into the grouting pipe (103), releasing pressure through a pressure relief valve (7), releasing air in the grouting pipe (103) in advance, calculating the flow rate and injection time, and after the anchoring agent enters the inner end of the grouting pipe (103), increasing the pressure injected by the grouting pump, The internal pressure of the grouting pipe (103) is increased. Since the pressure released is less than the pressure injected, the cross coating (108) is broken from the inside of the borehole to the outside and the anchoring agent flows out, so that the internal injection is uniform. Then the grouting pump and the grouting pipe (103) are disconnected, and then the connecting mechanism (4) is installed to complete the first stage of end anchoring. Then the anchor cable supporting tray lock is installed, and prestressing tension is applied. Finally, the grouting pump is connected to the grouting pipe (103) again, and the secondary grouting is performed according to the amount of slurry required for bonding the remaining anchor cable segment until the entire length of the anchor cable is anchored.

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