Long anchor cable anchoring device and anchoring method

Abstract

The invention provides a long anchor cable anchoring device and method, and relates to the technical field of anchor cable anchoring. The device comprises an anchoring assembly, a grouting assembly and an isolation assembly. The anchoring assembly comprises a steel strand, a long anchor cable tray and an anchorage device, the first end of the steel strand is used for being inserted into the long anchor cable hole, the second end of the steel strand is sequentially sleeved with the long anchor cable tray and the anchorage device, and the long anchor cable tray abuts against the hole opening rock surface of the long anchor cable hole; the grouting assembly comprises a grouting pipe and an exhaust pipe, the steel strand, the grouting pipe and the exhaust pipe are bundled and fixed to form a pipe bundle, and the grouting pipe is used for filling the long anchor cable hole with cement paste; the isolation assembly comprises an air bag, an inflation and exhaust pipe and a slurry stop sponge plug, the inflation and exhaust pipe is communicated with the air bag, the air bag and the tube bundle are detachably bundled and fixed, an insertion hole is formed in the center of the slurry stop sponge plug, the tube bundle penetrates through the insertion hole, and the slurry stop sponge plug is located on the upper side of the air bag. And the end part of the anchoring assembly is anchored in the long anchor cable hole, so that yielding support is realized, and the fracture possibility of the steel strand is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of anchor cable anchoring, in particular to a long anchor cable anchoring device and an anchoring method. Background Art

[0002] Long cable anchor support refers to anchoring steel strands inside the rock mass, connecting the loose surface rock mass with the deep stable rock mass through the steel strands, thereby changing the stress state of the underground tunnel and the mining area or slope rock mass, improving the mechanical properties of the rock mass, effectively controlling the displacement of the rock mass, improving the integrity and stability of the unstable rock mass, preventing the collapse of the surrounding rock, and ensuring the safety of underground operations. Therefore, long cable anchor support technology is widely used in mine tunnel support, tunnel engineering, underground chambers, slope reinforcement, foundation reinforcement and other projects.

[0003] In the long anchor cable support of the surrounding rock of underground tunnels and chamber walls and roofs in hard rock mines, cement slurry is usually used for full-length anchoring. However, full-length anchoring is a typical rigid support. Rigid support increases the support resistance and resists the deformation of the surrounding rock by increasing the rigidity of the support structure. The support structure is significantly more stressed. Since the deformation range of the support body is very limited, once the ultimate bearing capacity of the steel strand is exceeded, the steel strand will break, making the long anchor cable support ineffective, the surrounding rock will lose effective support, and will further continue to deform, the plastic zone will continue to increase, and eventually the tunnel surrounding rock will collapse, causing huge losses. Summary of the invention

[0004] For metal mines, due to the constraints of rock hardness and rock drilling equipment, the diameter of the long anchor hole is usually not less than ф55mm. If ф15.2mm or ф17.8mm steel strands are installed, due to the problem of three-diameter matching, only full-length anchor support with cement grouting can be used. The advantage of full-length anchor support is that the long anchor has high support rigidity and timely support resistance, but since the deformation range of the support body is very limited, once the ultimate bearing capacity of the steel strand is exceeded, the steel strand will break, making the long anchor support ineffective and the surrounding rock will lose effective support.

[0005] The end anchor support of long anchor cable is a support method that can achieve compression support. The bonded section of 1 / 3 of the steel strand (bottom end of the hole) is tightly bonded to the deep stable rock mass, and 2 / 3 of the steel strand is in a non-bonded state. The end of this section of steel strand (outside the hole) is fixed to the surface rock mass through the anchor and anchor tray. When the surface rock mass undergoes convergence deformation, the outer end of the steel strand hole moves with the long anchor cable tray and anchor and the surface rock mass. At this time, the bottom end of the hole is the fixed end, and the non-bonded steel strand section from the outer end of the hole to the bottom end of the hole 2 / 3 will undergo elongation deformation, providing continuous support force for the surface rock mass while allowing the surrounding rock surface to have a certain deformation, thereby achieving coordinated deformation of the support structure and the surrounding rock, fully releasing the high stress of the surrounding rock, and greatly reducing the force on the support structure compared to the rigid support of the long anchor cable with full-length anchoring, so that the surrounding rock-support force system is generally in a safe state. Therefore, how to achieve the end anchor of the grouting long anchor cable is a technical problem that urgently needs to be solved.

[0006] In order to solve the technical problem in the prior art that the deformation range of the support body is very limited, once the ultimate bearing capacity of the steel strand is exceeded, the steel strand will break, thereby making the long anchor cable support ineffective, the embodiment of the present invention provides a long anchor cable anchoring device and anchoring method. The technical solution is as follows:

[0007] In one aspect, a long anchor cable anchoring device is provided, the device comprising: an anchoring assembly, a grouting assembly and an isolation assembly;

[0008] The anchor assembly comprises a steel strand, a long anchor cable tray and an anchor, wherein the first end of the steel strand is used to be inserted into the long anchor cable hole, the long anchor cable tray and the anchor are sequentially sleeved on the second end of the steel strand, and the long anchor cable tray abuts against the rock surface of the hole opening of the long anchor cable hole;

[0009] The grouting assembly comprises a grouting pipe and an exhaust pipe. The steel strand, the grouting pipe and the exhaust pipe are bundled and fixed to form a pipe bundle. The grouting pipe is used to fill cement slurry into the long anchor cable hole.

[0010] The isolation assembly includes an airbag, an air inflation and exhaust pipe and a grout-stopping sponge plug. The air inflation and exhaust pipe is connected to the airbag. The airbag and the tube bundle are detachably bundled and fixed. The grout-stopping sponge plug has a plug hole in the center. The tube bundle passes through the plug hole, and the grout-stopping sponge plug is located on the upper side of the airbag.

[0011] Optionally, the device further comprises: a fixing piece, wherein the fixing piece is sleeved on the lower end of the outer wall of the slurry-stopping sponge plug.

[0012] Optionally, foam glue is used to seal and fill the space between the tube bundle and the grout-stopping sponge plug.

[0013] Optionally, the device further comprises: a fixing wedge, wherein the fixing wedge is arranged at a port of the long anchor cable hole.

[0014] Optionally, the lengths of the steel strand, the exhaust pipe, and the grouting pipe decrease sequentially.

[0015] On the other hand, a long anchor cable anchoring method is provided, the method comprising:

[0016] Tie and fix the steel strands, grouting pipes and exhaust pipes together to form a pipe bundle;

[0017] Insert the tube bundle into the insertion hole in the center of the grout-stopping sponge plug;

[0018] The airbag and the inflation and exhaust pipe are detachably bundled with the pipe bundle and inserted into a preset position in the long anchor cable hole;

[0019] Inflate the airbag through the inflation and exhaust pipe. When the inflation pressure reaches the preset pressure, the airbag bulges to support the stop sponge plug.

[0020] Inject grout into the long anchor cable hole through a grouting pipe, and stop grouting after cement slurry flows out of the exhaust pipe;

[0021] After the grouting is completed for the first preset time, the gas in the airbag is discharged, and the airbag and the grouting pipe are recovered;

[0022] After the grouting is completed for the second preset time, the long anchor cable tray and anchor are installed.

[0023] Optionally, after inserting the tube bundle into the insertion hole at the center of the grout-stopping sponge plug, the method further comprises:

[0024] A fixing piece is used to bind the lower end of the outer wall of the grout-stopping sponge plug so as to fix the grout-stopping sponge plug and the tube bundle together.

[0025] Optionally, after the fixing member is used to bind the lower end of the outer wall of the grout-stopping sponge plug to fix the grout-stopping sponge plug and the tube bundle together, the method further includes:

[0026] The gap between the tube bundle and the grout-stopping sponge plug is sealed with foam glue.

[0027] Optionally, after the airbag and the inflation and exhaust pipe are detachably bundled with the tube bundle and inserted into a preset position in the long anchor cable hole, the method further includes:

[0028] A fixing wedge is used to fix the end of the long anchor cable hole.

[0029] Optionally, the grouting into the long anchor cable hole through a grouting pipe includes: injecting cement slurry with a water-cement ratio of 0.4-0.8 into the long anchor cable hole through a grouting pipe.

[0030] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0031] The long anchor cable anchoring device provided in this embodiment includes an anchor assembly, a grouting assembly and an isolation assembly. After the anchor assembly is inserted into the long anchor cable hole, the isolation assembly is used to temporarily fix the anchor assembly, and grouting is performed into the long anchor cable hole through the grouting assembly. At this time, the isolation assembly can also play a role in isolating cement slurry, so that the end of the anchor assembly can be anchored in the long anchor cable hole. The device realizes the end anchor support of the grouting long anchor cable, and can use the elongation of the steel strand to achieve the purpose of pressure-yielding support, reduce the possibility of steel strand breakage, avoid the failure of the long anchor cable, and reduce the maintenance and repair costs of the tunnel under high ground pressure and large deformation rock conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 It is a structural schematic diagram of a long anchor cable anchoring device provided by an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the main structure of a grout-stopping sponge plug provided by an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the top view of a grout-stopping sponge plug provided by an embodiment of the present invention;

[0036] Figure 4 is a schematic structural diagram of an airbag provided by an embodiment of the present invention;

[0037] Figure 5 It is a schematic diagram of a state of an air bag provided by an embodiment of the present invention after being inflated in a long anchor cable hole;

[0038] Figure 6 It is a structural schematic diagram of a steel strand, a grouting pipe and an exhaust pipe binding provided by an embodiment of the present invention;

[0039] Figure 7 It is a schematic diagram of a binding structure of a steel strand, a grouting pipe, an exhaust pipe and a grout-stopping sponge plug provided by an embodiment of the present invention;

[0040] Figure 8 yes Figure 7 The structural diagram of section A in the middle;

[0041] Fig. 9It is a schematic diagram of the structure of an air bag and an inflation and exhaust pipe after being tied with a steel strand, a grouting pipe, an exhaust pipe and a grout-stopping sponge plug plate provided by an embodiment of the present invention;

[0042] Fig.10 yes Fig. 9 The structural diagram of the middle section B;

[0043] Fig.11 It is a structural schematic diagram of a state where an air bag provided by an embodiment of the present invention is fully expanded in a long anchor cable;

[0044] Fig.12 It is a structural schematic diagram of a long anchor cable state after the air bag and the grouting pipe are recovered provided by an embodiment of the present invention;

[0045] Fig.13 It is a flow chart of a long anchor cable anchoring method provided by an embodiment of the present invention.

[0046] Reference numerals:

[0047] 100, anchoring assembly; 110, steel strand; 120, long anchor cable tray; 130, anchor; 140, fixing belt;

[0048] 200, grouting assembly; 210, grouting pipe; 220, exhaust pipe; 230, cement slurry; 240, concrete;

[0049] 300, isolation assembly; 310, air bag; 320, inflation and exhaust pipe; 330, grout-stopping sponge plug; 331, jack; 332, fixing piece;

[0050] 400, fixed wedge;

[0051] 510. Long anchor cable hole; 520. Tunnel roof. DETAILED DESCRIPTION

[0052] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0053] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0054] For metal mines, due to the constraints of rock hardness and rock drilling equipment, the diameter of the long anchor hole is usually not less than ф55mm. If ф15.2mm or ф17.8mm steel strands are installed, due to the problem of three-diameter matching, only full-length anchor support with cement grouting can be used. The advantage of full-length anchor support is that the long anchor has high support rigidity and timely support resistance, but since the deformation range of the support body is very limited, once the ultimate bearing capacity of the steel strand is exceeded, the steel strand will break, making the long anchor support ineffective and the surrounding rock will lose effective support.

[0055] The end anchor support of long anchor cable is a support method that can achieve compression support. The bonded section of 1 / 3 of the steel strand (bottom end of the hole) is tightly bonded to the deep stable rock mass, and 2 / 3 of the steel strand is in a non-bonded state. The end of this section of steel strand (outside the hole) is fixed to the surface rock mass through the anchor and anchor tray. When the surface rock mass undergoes convergence deformation, the outer end of the steel strand hole moves with the long anchor cable tray and anchor and the surface rock mass. At this time, the bottom end of the hole is the fixed end, and the non-bonded steel strand section from the outer end of the hole to the bottom end of the hole 2 / 3 will undergo elongation deformation, providing continuous support force for the surface rock mass while allowing the surrounding rock surface to have a certain deformation, thereby achieving coordinated deformation of the support structure and the surrounding rock, fully releasing the high stress of the surrounding rock, and greatly reducing the force on the support structure compared to the rigid support of the long anchor cable with full-length anchoring, so that the surrounding rock-support force system is generally in a safe state. Therefore, how to achieve the end anchor of the grouting long anchor cable is a technical problem that urgently needs to be solved.

[0056] An embodiment of the present invention provides a long anchor cable anchoring device. To make the technical problems, technical solutions and advantages to be solved by the present invention clearer, it will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0057] The long anchor cable anchoring device comprises: an anchor assembly 100, a grouting assembly 200 and an isolation assembly 300. After the anchor assembly 100 is inserted into the long anchor cable hole 510, the isolation assembly 300 is used to temporarily fix the anchor assembly 100, and grouting is injected into the long anchor cable hole 510 through the grouting assembly 200. At this time, the isolation assembly 300 can also play a role in isolating the cement slurry 230, so that the end of the anchor assembly 100 can be anchored in the long anchor cable hole 510.

[0058] Among them, the long anchor cable is to first drill a deeper hole in the rock formation, then send the steel strand, wire rope or rebar into the hole, and make it tightly combined with the surrounding rock mass through grouting and other methods, so as to provide strong anchoring force. The essence of the long anchor cable is to form a strong anchoring system in the rock formation, and make the steel strand, wire rope or rebar tightly combined with the surrounding rock mass through grouting and other methods, so as to provide stable anchoring force.

[0059] It should be noted that the device provided in this embodiment adopts an end anchor anchoring method, which specifically refers to a short anchoring length of anchoring materials such as anchor rods or steel strands in structural materials such as rock or concrete, usually not more than 1 / 3 or 2 / 3 of the total length of the anchor rod or steel strand. This anchoring method mainly achieves a fixing effect by injecting an anchoring agent into one end of the anchor rod or steel strand so that it is tightly bonded to the internal structure of the rock or concrete 240.

[0060] In the device, the anchoring assembly 100 includes a steel strand 110, a long anchor cable tray 120 and an anchor 130. The first end of the steel strand 110 is used to be inserted into the long anchor cable hole 510. The long anchor cable tray 120 and the anchor 130 are sequentially mounted on the second end of the steel strand 110, and the long anchor cable tray 120 is against the rock surface of the hole mouth of the long anchor cable hole 510.

[0061] Specifically, the steel strand 110 has high strength and flexibility, which enables it to adapt to complex geological conditions and effectively transmit and disperse stress. The first end of the steel strand 110 is inserted into the pre-drilled long anchor hole 510, the hole is blocked, and grout is injected into the hole, so that the steel strand can be cemented to the bedrock with cement slurry. The long anchor tray 120 is used to connect the stable rock mass in the deep part of the tunnel with the unstable rock mass on the surface of the tunnel through the steel strand, and to prevent the rock mass on the surface of the tunnel from moving and deforming through the anchor and the anchor tray. The tray is tightly against the rock surface at the hole of the long anchor hole 510, and the surface rock mass can be tightly connected to the deep stable rock mass through the steel strand to achieve a firm anchoring of the surface rock mass. The anchor 130 is used to lock the steel strand 110 to ensure that there is no relative displacement between the second end of the steel strand 110 and the tray in the working state. The anchor 130 works with the tray to lock one end of the steel strand, providing a strong locking force for the entire anchor assembly 100. During use, the other end is locked with the deep rock mass through grouting. Therefore, if the surface rock mass of the tunnel converges and deforms toward the inside of the tunnel, it will drive the anchor cable tray to move inward at the same time. The anchor cable tray is tightly fitted or locked with the steel strand through the anchor, and the other end of the steel strand is fixed to the stable shelter inside. The steel strand, anchor and tray can prevent the surface rock mass of the tunnel from converging and deforming inward.

[0062] The grouting assembly 200 includes a grouting pipe 210 and an exhaust pipe 220. The steel strand 110, the grouting pipe 210 and the exhaust pipe 220 are bundled and fixed to form a pipe bundle. This structure is convenient for construction operation and can ensure smooth grouting and exhaust. Specifically, it can be bundled and fixed with a fixing belt 140. For example, the fixing belt 140 can be a cable tie.

[0063] The grouting pipe 210 is used to fill the long anchor cable hole 510 with cement slurry 230. The cement slurry 230 is injected into the long anchor cable hole 510 through the above-mentioned grouting pipe 210. After the cement slurry 230 solidifies in the hole, it forms a high-strength grouting body, which enhances the bonding force between the steel strand 110 and the bedrock, thereby improving the anchoring effect. Since the hole is a closed space, during the grouting process, as the grouting liquid is gradually injected into the hole, the air enclosed in the hole is gradually discharged from the exhaust pipe 220, ensuring that the cement slurry 230 can fully fill the internal space formed by the grouting section steel strand 110 and the long anchor cable hole 510.

[0064] The isolation assembly 300 includes an airbag 310, an inflation and exhaust pipe 320, and a grout-stopping sponge plug 330. The inflation and exhaust pipe 320 is connected to the airbag 310 and is used to control the inflation and deflation of the airbag 310. The airbag 310 and the tube bundle are detachably tied and fixed. The grout-stopping sponge plug 330 has a plug hole 331 at the center, and the tube bundle passes through the plug hole 331. The grout-stopping sponge plug 330 is located on the upper side of the airbag 310.

[0065] After being inflated, the airbag 310 can be closely attached to the inner wall of the long anchor hole 510 to support the grouting sponge plug 330. The softness and deformability of the grouting sponge plug 330 can adapt to the unevenness of the inner wall of the hole, and further prevent the cement slurry 230 from penetrating out of the hole wall of the long anchor hole 510, thereby enhancing the isolation effect. At the same time, it can also provide a certain sealing effect after the grouting is completed.

[0066] For most underground mines, long anchor cables are usually installed on the side walls of the tunnel, the roof or the roof of the mining area. Due to the high hardness of the rock mass in hard rock mines, rods need to be connected to drill holes, resulting in a larger aperture of the long anchor cable hole 510. Therefore, through this embodiment, when supporting the long anchor cable in the tunnel, chamber or the roof of the mining area, the steel strand 110, the grouting pipe 210, the exhaust pipe 220 and the grouting sponge plug are first tied into a bundle, and then the air bag 310 and the inflation and exhaust pipe 320 are tied together with the above-mentioned steel strand 110 and the grouting pipe 210, and then put into the long anchor cable hole 510, the air bag 310 is inflated, and the cavity in the long anchor cable hole 510 above the air bag 310 is grouted. After the grouting is completed, After the first preset time, the air in the airbag 310 is discharged, and the airbag 310 and the grouting pipe 210 are recovered. After the grouting is completed for the second preset time, the long anchor cable tray 120 and the anchor 130 are installed, thereby realizing the end anchor support of the grouting long anchor cable. The elongation of the steel strand 110 can be used to achieve the purpose of pressure-relieving support, reducing the possibility of steel strand breakage, avoiding the failure of the long anchor cable, and reducing the maintenance and repair costs of the tunnel under high ground pressure and large deformation rock conditions.

[0067] The long anchor cable anchoring device provided in this embodiment includes an anchor assembly 100, a grouting assembly 200 and an isolation assembly 300. After the anchor assembly 100 is inserted into the long anchor cable hole 510, the isolation assembly 300 is used to temporarily fix the anchor assembly 100, and grouting is performed into the long anchor cable hole 510 through the grouting assembly 200. At this time, the isolation assembly 300 can also play the role of isolating the cement slurry 230, so that the end of the anchor assembly 100 can be anchored in the long anchor cable hole 510. The device realizes the end anchor support of the grouting long anchor cable, and can use the elongation of the steel strand 110 to achieve the purpose of pressure-yielding support, reduce the possibility of steel strand breakage, avoid the failure of the long anchor cable, and reduce the maintenance and repair costs of the tunnel under high ground pressure and large deformation rock conditions.

[0068] Compared with full-length cementation anchoring, the use of this device for end anchor support also reduces the amount of grouting per hole and the consumption of raw materials, thereby improving construction efficiency. Furthermore, based on the reusable inflatable airbag 310 and grouting pipe 210, the cost of single-use materials is reduced, thereby reducing support costs.

[0069] In an embodiment provided by the present invention, the device further includes: a fixing member 332 , which is sleeved on the lower end of the outer wall of the grout-stopping sponge plug 330 .

[0070] The fixing piece 332 can be used to firmly sleeve the grout-stopping sponge plug 330 outside the tube bundle. On the one hand, it can fix the tube bundle. On the other hand, since the grout-stopping sponge plug 330 can be deformed, the gap between the grout-stopping sponge plug 330 and the tube bundle can be sealed, thereby preventing the cement slurry 230 from leaking during the grouting process. The use of the fixing piece 332 further enhances the stability and use effect of the grout-stopping sponge plug 330, and improves the sealing and stability of the overall structure.

[0071] Furthermore, the fixing member 332 may be a cable tie, which is easy to operate, low in cost, and has a good fastening effect. When in use, the cable tie can be easily wrapped around the lower end of the outer wall of the stop sponge plug 330 and tightened, and the cable tie can be fixed by its own tooth buckle, thereby effectively fixing the stop sponge plug 330. The cable tie has a certain elasticity and adaptability, and can adapt to stop sponge plugs 330 of different diameters and shapes, increasing the flexibility and wide range of use.

[0072] In one embodiment provided by the present invention, foam glue is sealed and filled between the tube bundle and the stop sponge plug 330. Foam glue, also known as foam glue or polyurethane foam sealant, has excellent sealing, bonding and filling properties. It can form a continuous, seamless sealing layer between the tube bundle and the stop sponge plug 330, effectively preventing the penetration of cement slurry 230, and ensuring the sealing and integrity of the tube bundle assembly.

[0073] In one embodiment provided by the present invention, the device further comprises: a fixing wedge 400, which is arranged at the end of the long anchor cable hole 510. The main function of the fixing wedge 400 is to firmly fix the position of the pipe bundle in the long anchor cable hole 510, and prevent the steel strand from slipping out of the hole and injuring people or becoming loose due to its own weight after the steel strand is installed in the hole until the grouting is completed and solidified.

[0074] Furthermore, the fixing wedge 400 may be a wooden wedge.

[0075] In one embodiment provided by the present invention, the lengths of the steel strand 110, the exhaust pipe 220, and the grouting pipe 210 are sequentially reduced. Based on this structure, when the device is set in a long anchor cable hole 510 with an opening facing downward, the positions of the ends of the steel strand 110, the exhaust pipe 220, and the grouting pipe 210 are sequentially reduced.

[0076] Based on the above structure, a grouting machine is used to inject cement slurry 230 into the long anchor cable hole 510 through the grouting pipe 210. After the cement slurry 230 enters the internal space above the grouting sponge plug 330, the excess gas is discharged through the exhaust pipe 220. After the cement slurry 230 flows out of the exhaust pipe 220, it indicates that the long anchor cable hole 510 is full and the grouting can be stopped.

[0077] The long anchor cable anchoring device provided in this embodiment includes an anchor assembly 100, a grouting assembly 200 and an isolation assembly 300. After the anchor assembly 100 is inserted into the long anchor cable hole 510, the isolation assembly 300 is used to temporarily fix the anchor assembly 100, and grouting is performed into the long anchor cable hole 510 through the grouting assembly 200. At this time, the isolation assembly 300 can also play the role of isolating the cement slurry 230, so that the end of the anchor assembly 100 can be anchored in the long anchor cable hole 510. The device realizes the end anchor support of the grouting long anchor cable, and can use the elongation of the steel strand 110 to achieve the purpose of pressure-yielding support, reduce the possibility of steel strand breakage, avoid the failure of the long anchor cable, and reduce the maintenance and repair costs of the tunnel under high ground pressure and large deformation rock conditions.

[0078] Compared with full-length cementation anchoring, the use of this device for end anchor support also reduces the amount of grouting per hole and the consumption of raw materials, thereby improving construction efficiency. Furthermore, based on the reusable inflatable airbag 310 and grouting pipe 210, the cost of single-use materials is reduced, thereby reducing support costs.

[0079] The following describes the long anchor cable anchoring device provided by the present invention by taking the long anchor cable hole 510 with a diameter of ф60mm and a hole depth of 6m commonly used in underground mines as an example. The steel strand 110 used can be ф15.2mm, ф17.8mm or other specifications of steel strand 110, and each hole can use a single strand or two strands. The following only installs a single ф15.2mm steel strand 110 in one hole. If a specific mine selects different steel strands 110 or the depth of the long anchor cable hole 510, etc., it can be achieved by making corresponding subtle adjustments.

[0080] Specifically, the anchor assembly 100 includes a steel strand 110, a long anchor cable tray 120 and an anchor 130, which is the main force-bearing and force-transmitting device, that is, the anchor 130 and the long anchor cable tray 120 are used to apply a force to constrain the convergence and deformation of the surrounding rock on the surface of the tunnel, and this constraint force is transmitted to the stable rock layer deep in the surrounding rock through the steel strand 110, so as to achieve the interlocking of the deep rock mass and the surface rock mass of the tunnel or the mining area. The steel strand 110 can be a single steel strand 110 of ф15.2mm and 6.3m in length. The long anchor cable tray 120 can be of a specification of length×width×thickness of 200mm×200mm×20mm, made of Q235, and a ф18mm hole is drilled in the middle of the tray; the anchor 130 is of KM15-1860 type, and the anchor 130 is installed with a front jack;

[0081] The grouting assembly 200 includes a grouting pipe 210 and an exhaust pipe 220, and its main function is to firmly fix the steel strand 110 in the long anchor cable hole 510 through cement grouting. Of course, the grouting pipe 210 is connected to a grouting pump, and the function of the grouting pump is to inject the prepared cement slurry 230 with a water-cement ratio of about 0.5 into the long anchor cable hole 510 through the grouting pipe 210; the function of the exhaust pipe 220 is that when the grouting liquid gradually rises from bottom to top in the long anchor cable hole 510, the air enclosed in the upper part of the long anchor cable hole 510 can be discharged along the exhaust pipe 220 to ensure that the long anchor cable hole 510 is filled with cement slurry 230. When the grouting operator sees the slurry flowing out of the exhaust pipe 220, it means that the long anchor cable hole 510 has been filled, and the grouting can be stopped immediately; the grouting pipe 210 is the channel for the grouting liquid to reach the long anchor cable hole 510 from the grouting pump. The grouting pipe 210 has an outer diameter of ф20mm, a wall thickness of 2mm, and is made of materials such as PE (Polyethylene, a thermoplastic resin formed by polymerization of ethylene), and can bear a pressure of 0.2-0.4MPa; the exhaust pipe 220 has an outer diameter of ф10mm, a wall thickness of 1-1.5mm, and is made of materials such as PE;

[0082] The isolation assembly 300 is composed of a grout-stopping sponge plug 330, an air bag 310 and an inflating and exhausting pipe 320. The main purpose is to realize the end anchoring of the long anchor cable. The grout-stopping sponge plug 330 is cylindrical, with a diameter of ф75mm and a height of 80mm. The center of the cylinder is a plug hole 331 with a flat hole structure (see Figures 2 to 3 As shown), it is used to pass the steel strand 110, the exhaust pipe 220 and the grouting pipe 210 therethrough.

[0083] The diameter of the grouting sponge plug 330 is 15 mm larger than the diameter of the long anchor hole 510. By utilizing its superior deformability and elastic properties, it can not only be tied to the steel strand 110, the exhaust pipe 220 and the grouting pipe 210, and smoothly sent into the designed position in the hole along with these pipe bundles, but also by utilizing its own deformability, the grouting sponge plug 330 can be relatively sealed with the hole wall and the steel strand 110, the grouting pipe 210 and the exhaust pipe 220, preventing the cement slurry 230 from flowing out of the hole from the gaps between the above-mentioned components; at the same time, in order to further prevent the possible leakage of cement slurry 230 between the above-mentioned components, it is necessary to tie the grouting sponge plug 330, the steel strand 110, the grouting pipe 210 and the exhaust pipe 220 together, and before sending them into the hole, reinforce the gaps between the above-mentioned components with foam glue to ensure that there is no risk of error.

[0084] In this embodiment, considering the low strength of the grout-stopping sponge plug 330, an airbag 310 is designed and installed to further prevent the cement slurry 230 from flowing out of the hole. It not only provides a good bottom support for the grout-stopping sponge plug 330, but also serves as a second barrier to prevent the slurry from flowing out, and is an important component for realizing the end anchor. The airbag 310 is made of synthetic rubber and fiber cloth, or TPU (Thermoplastic polyurethanes), PVC (Polyvinyl Chloride) and other materials. The airbag 310 is in the shape of a flat bag when not inflated. The specifications of the airbag 310 are 80mm in height and 280mm in length. The airbag 310 is connected to an inflation and exhaust pipe 320 (structure as shown in FIG. 1 ) with a specification of ф8mm×7m. Figure 4 As shown), the airbag 310 can be bent and folded in the uninflated state, and can be used to wrap the steel strand 110, the exhaust pipe 220 and the grouting pipe 210.

[0085] When the airbag 310 is filled with air in the hole, the actual state of each component is as follows: Figure 5 In this embodiment, the inflation and exhaust pipe 320 is made of PVC material, has a length of 6.5m, an outer diameter of ф10mm, and a wall thickness of 2mm.

[0086] The beneficial effects of the long anchor cable anchoring device include:

[0087] (1) The long anchor cable anchoring device enables the long anchor cable of grouting type bonding in hard rock mines to achieve end anchor support. Due to the limitation of the rock drilling equipment in hard rock mines, it is impossible to drill a long anchor cable hole 510 that meets the three-diameter matching, can be bonded with resin anchoring agent and achieve end anchor support. The usual long anchor cable bonding adopts cement slurry 230 bonding. For the long anchor cable in the mining field or the side and top of the tunnel, only the full-length bonding anchoring method can be adopted. In the high-stress environment, the deformation and damage of the rock mass will cause the stress to concentrate on a certain area of ​​the long anchor cable (usually near the surface of the tunnel), which can easily cause the steel strand 110 to be pulled off, the long anchor cable support to fail, and the pressure-yielding support cannot be achieved. However, the advantage of the end long anchor cable support bonded with resin anchoring agent in coal mines cannot be applied to the long anchor cable support in hard rock mines. The long anchor cable anchoring device allows the grouting bonding to act only on the end of the long anchor cable. The advantage of the long anchor cable end bonding support is that the extension characteristics of the steel strand 110 can allow partial deformation of the rock mass, but at the same time, based on the super-strong tension of the steel strand 110, it provides continuous support resistance to the surrounding rock on the surface of the tunnel, realizing compression support. This support method can significantly extend the service life of the engineering structure and reduce the frequency and cost of maintenance and repair of the tunnel.

[0088] (2) The long anchor cable anchoring device reduces the cement slurry consumption of single-hole grouting by 230%, reducing the original single-hole grouting volume from 100% to more than 33%, further reducing the grouting cost;

[0089] (3) The long anchor cable anchoring device can reuse the inflatable airbag 310 and the grouting pipe 210, which reduces the cost of single-use materials, reduces support costs, and saves resources;

[0090] (4) The installation process of the airbag 310 is relatively simple, and the airbag 310 can be quickly inflated based on the high-pressure wind source used for underground rock drilling and reach a predetermined shape and size, with high construction efficiency. At the same time, there is no need to seal the long anchor cable hole 510, which shortens the 24-hour maintenance period required for traditional cement slurry 230 sealing and curing, and shortens the overall construction period of the long anchor cable support.

[0091] The present invention also provides a long anchor cable anchoring method. Fig.13 This is a flow chart of a long anchor cable anchoring method provided by an embodiment of the present invention, please refer to Fig.13 The method comprises:

[0092] 1301. Tie and fix the steel strands 110, the grouting pipes 210, and the exhaust pipes 220 together to form a pipe bundle.

[0093] In this step, the steel strand 110 , the grouting pipe 210 , and the exhaust pipe 220 are tied together with a cable tie to facilitate insertion into the long anchor cable hole 510 .

[0094] 1302. Insert the tube bundle into the insertion hole 331 at the center of the grout-stopping sponge plug 330.

[0095] The softness and water absorption of the grout-stopping sponge plug 330 can further prevent the penetration of the cement slurry 230, thereby enhancing the isolation effect.

[0096] Furthermore, it also includes: using a fixing piece 332 to tie the lower end of the outer wall of the grout-stopping sponge plug 330 to fix the grout-stopping sponge plug 330 and the tube bundle together. The fixing piece 332 can firmly cover the grout-stopping sponge plug 330 outside the tube bundle, which can fix the tube bundle on the one hand, and on the other hand, since the grout-stopping sponge plug 330 can be deformed, the gap between the grout-stopping sponge plug 330 and the tube bundle can be sealed, thereby preventing the cement slurry 230 from leaking during the pouring process. The use of the fixing piece 332 further enhances the stability and use effect of the grout-stopping sponge plug 330, and improves the sealing and stability of the overall structure.

[0097] Furthermore, the fixing member 332 may be a cable tie, which is easy to operate, low in cost, and has a good fastening effect. When in use, the cable tie can be easily wrapped around the lower end of the outer wall of the stop sponge plug 330 and tightened, and the cable tie can be fixed by its own tooth buckle, thereby effectively fixing the stop sponge plug 330. The cable tie has a certain elasticity and adaptability, and can adapt to stop sponge plugs 330 of different diameters and shapes, increasing the flexibility and wide range of use.

[0098] Furthermore, the method further includes: sealing and filling the gap between the tube bundle and the grout-stopping sponge plug 330 with foam glue.

[0099] Foam glue, also known as foam glue or polyurethane foam sealant, has excellent sealing, bonding and filling properties. It can form a continuous and seamless sealing layer between the tube bundle and the grout stopper sponge plug 330, effectively preventing the penetration of cement slurry 230 and ensuring the sealing and integrity of the tube bundle assembly.

[0100] 1303. The airbag 310 and the inflation and exhaust pipe 320 are detachably bundled with the tube bundle and inserted into the preset position in the long anchor cable hole 510.

[0101] This step is used to prepare for subsequent grouting. For example, the detachable bundling airbag 310 and the inflation and exhaust pipe 320 and the pipe bundle can be bundled with plastic tape, which can be bundled and easily broken by the airbag 310.

[0102] Furthermore, it also includes: using a fixing wedge 400 to fix the end of the long anchor hole 510. The main function of the fixing wedge 400 is to firmly fix the position of the pipe bundle in the long anchor hole 510 to prevent the steel strand from slipping out of the hole due to its own weight and injuring people or becoming loose after the steel strand is installed in the hole until the grouting is completed and solidified.

[0103] 1304. Inflate the airbag 310 through the inflation and exhaust pipe 320. When the inflation pressure reaches the preset pressure, the airbag 310 bulges to support the stop sponge plug 330.

[0104] The airbag 310 is inflated through the inflation and exhaust pipe 320. When the inflation pressure reaches the preset pressure, the airbag 310 bulges, and the plastic tape connecting the airbag 310 and the steel strand 110, the grouting pipe 210, and the exhaust pipe 220 to form the pipe bundle is torn and fully inflated. The airbag 310 is fully filled between the pipe bundle and the inner wall of the long anchor hole 510, completing the support of the grouting sponge plug 330, and can prevent the cement slurry 230 from flowing out during future grouting. It can also prevent the pipe bundles from sliding out of the hole based on the friction between the airbag 310 and the above-mentioned pipe bundles and the airbag 310 and the hole wall. Among them, the preset inflation pressure corresponding to the airbag 310 can be set as needed, for example, it can reach 0.1-0.2MPa.

[0105] 1305. Inject grout into the long anchor cable hole 510 through the grouting pipe 210, and stop grouting after cement slurry 230 flows out of the exhaust pipe 220.

[0106] Further, this step includes: injecting cement slurry 230 with a water-cement ratio of 0.4-0.8 into the long anchor cable hole 510 through the grouting pipe 210. Specifically, the grouting pipe 210 of the grouting machine is tightly connected with the grouting pipe 210 of the long anchor cable, and then the grouting machine is used to inject cement slurry 230 with a water-cement ratio of about 0.5 into the long anchor cable hole 510. When the cement slurry 230 is found to flow out of the exhaust pipe 220, it indicates that the long anchor cable hole 510 has been filled, and the grouting is stopped immediately.

[0107] 1306. After the grouting is completed for the first preset time, the gas in the airbag 310 is discharged, and the airbag 310 and the grouting pipe 210 are recovered.

[0108] After the grouting is finished for the first preset time, the valve of the inflation and exhaust pipe 320 is untied, the gas in the airbag 310 is leaked, and then the inflation and exhaust pipe 320 of the airbag 310 and the grouting pipe 210 are dragged at the same time, so that the airbag 310 and its inflation and exhaust pipe 320 and the grouting pipe 210 can be recovered, and the grouting pipe 210 can be cleared as soon as possible and then reused next time. Among them, the first preset time can be set as needed, for example, it can be 3-5 hours after the grouting is completed.

[0109] 1307. After the grouting is completed for the second preset time, the long anchor cable tray 120 and the anchor 130 are installed.

[0110] Specifically, the long anchor cable tray 120 and the anchor 130 may be installed using a front jack. After the grouting is completed for the second preset time, the long anchor cable tray 120 and the anchor 130 are installed using a front jack to complete the installation of the long anchor cable. The second preset time can be set as needed, for example, it can be 48 hours after the grouting is completed.

[0111] The long anchor cable anchoring method provided in this embodiment includes an anchor assembly 100, a grouting assembly 200 and an isolation assembly 300. After the anchor assembly 100 is inserted into the long anchor cable hole 510, the isolation assembly 300 is used to temporarily fix the anchor assembly 100, and grouting is performed into the long anchor cable hole 510 through the grouting assembly 200. At this time, the isolation assembly 300 can also play the role of isolating the cement slurry 230, so that the end of the anchor assembly 100 can be anchored in the long anchor cable hole 510. The device realizes the end anchor support of the grouting long anchor cable, and can use the elongation of the steel strand 110 to achieve the purpose of pressure-yielding support, reduce the possibility of steel strand breakage, avoid the failure of the long anchor cable, and reduce the maintenance and repair costs of the tunnel under high ground pressure and large deformation rock conditions.

[0112] In this embodiment, a long anchor hole 510 with a size of ф60mm×6m is drilled in the tunnel roof 520 as an example, and a steel strand 110 with a size of ф15.24mm×6.3m is to be installed, and the reserved length of the steel strand 110 outside the hole is 300mm. The steel strand 110 is bonded with 2m of cement slurry 230 near the bottom of the hole, and the remaining 4m of the steel strand 110 in the hole remains free and unbonded. The specific installation steps are as follows:

[0113] (1) After the long anchor hole 510 is drilled, use high-pressure water and high-pressure air to clean the rock powder and other debris in the hole;

[0114] (2) Tie the steel strand 110, the grouting pipe 210, and the exhaust pipe 220 together with cable ties. The spacing between the tying points is about 1 m. There is a 100 mm spacing between the exhaust pipe 220 head and the end of the steel strand 110, and a 2 m spacing between the grouting pipe 210 head and the end of the steel strand 110. Figure 6 shown.

[0115] (3) Insert the bundle formed by the tied steel strands 110, the grouting pipe 210, and the exhaust pipe 220 into the insertion hole 331 at the center of the grouting sponge plug 330, and then use a cable tie to tie the lower end of the sponge plug to the bundle. The specific position is as follows: Figures 7 and 8As shown, it is convenient to put it into the long anchor cable hole 510. At the same time, in order to ensure the airtightness between the grouting pipe 210, the steel strand 110, the exhaust pipe 220 and the plug hole 331 of the stop sponge plug 330, after the stop sponge plug 330 is tied, the gap between the steel strand 110, the grouting pipe 210, the exhaust pipe 220 and the stop sponge plug 330 is further sealed with foam glue to ensure that the cement slurry 230 does not leak.

[0116] (4) The airbag 310 and the inflation and exhaust pipe 320 are then tied together with the above-mentioned pipe bundle with a plastic tape. The advantage of the plastic tape is that the plastic tape can be stretched out after the airbag 310 is inflated. Figures 9 and 10 As shown, it is convenient to smoothly deliver the above components into the hole;

[0117] (5) Carefully insert the above-mentioned pipe bundles into the predetermined position in the long anchor hole 510 of ф60mm×6m, and then fix the hole mouth with a fixing wedge 400 to prevent the above-mentioned pipe bundles from slipping out of the hole. Then, inflate the airbag 310 through the inflation and exhaust pipe 320. When the inflation pressure reaches 0.1-0.2MPa, the airbag 310 bulges, cracking the plastic tape connecting the airbag 310 with the steel strand 110, the grouting pipe 210, and the exhaust pipe 220 to form the pipe bundle, and fully inflate, completing the support of the grouting sponge plug 330 (such as Fig.11 and Figure 5 As shown in FIG. 1 ), the cement slurry 230 can be prevented from flowing out during future grouting, and the friction between the airbag 310 and the above-mentioned tube bundles and the airbag 310 and the hole wall can also prevent the tube bundles from sliding out of the hole. After the airbag 310 is inflated, the mouth of the inflation and exhaust pipe 320 is tied tightly to prevent gas leakage.

[0118] (6) Tightly connect the grouting pipe 210 of the grouting machine with the grouting pipe 210 of the long anchor cable, and then use the grouting machine to inject cement slurry 230 with a water-cement ratio of about 0.5 into the long anchor cable hole 510. When cement slurry 230 is found to flow out of the exhaust pipe 220, it indicates that the long anchor cable hole 510 is full, and grouting is stopped immediately. The state after grouting is completed is as follows Figure 1 As shown;

[0119] (7) 3-5 hours after the grouting is completed, the cement slurry 230 has initially solidified, but has not yet formed a certain strength. At this time, the valve of the inflation and exhaust pipe 320 is opened to allow the gas in the airbag 310 to escape. Then, the inflation and exhaust pipe 320 of the airbag 310 and the grouting pipe 210 are dragged at the same time, and the airbag 310 and its inflation and exhaust pipe 320 and the grouting pipe 210 can be recovered (e.g. Fig.12 As shown), clear the grouting pipe 210 as soon as possible and reserve it for reuse next time;

[0120] (8) 48 hours after the grouting is completed, the anchor 130 and the long anchor cable tray 120 are installed using a jack to complete the installation of the long anchor cable.

[0121] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0122] In the present invention, "at least one" means one or more, and "plurality" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0123] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0124] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A long anchor cable anchoring device, characterized in that: The device comprises: an anchoring component, a grouting component and an isolation component; The anchor assembly comprises a steel strand, a long anchor cable tray and an anchor, wherein the first end of the steel strand is used to be inserted into the long anchor cable hole, the long anchor cable tray and the anchor are sequentially sleeved on the second end of the steel strand, and the long anchor cable tray abuts against the rock surface of the hole opening of the long anchor cable hole; The grouting assembly comprises a grouting pipe and an exhaust pipe. The steel strand, the grouting pipe and the exhaust pipe are bundled and fixed to form a pipe bundle. The grouting pipe is used to fill cement slurry into the long anchor cable hole. The isolation assembly includes an airbag, an air inflation and exhaust pipe and a grout-stopping sponge plug. The air inflation and exhaust pipe is connected to the airbag. The airbag and the tube bundle are detachably bundled and fixed. The grout-stopping sponge plug has a plug hole in the center. The tube bundle passes through the plug hole, and the grout-stopping sponge plug is located on the upper side of the airbag.

2. The long anchor cable anchoring device according to claim 1, characterized in that: The device also includes a fixing piece, which is sleeved on the lower end of the outer wall of the grout-stopping sponge plug.

3. The long anchor cable anchoring device according to claim 1, characterized in that: The tube bundle and the grout-stopping sponge plug are sealed and filled with foam glue.

4. The long anchor cable anchoring device according to claim 1, characterized in that: The device further comprises: a fixing wedge, wherein the fixing wedge is arranged at the end of the long anchor cable hole.

5. The long anchor cable anchoring device according to claim 1, characterized in that: The lengths of the steel strand, the exhaust pipe and the grouting pipe decrease in sequence.

6. A long anchor cable anchoring method, characterized in that: The method comprises: Tie and fix the steel strands, grouting pipes and exhaust pipes together to form a pipe bundle; Insert the tube bundle into the insertion hole in the center of the grout-stopping sponge plug; The airbag and the inflation and exhaust pipe are detachably bundled with the pipe bundle and inserted into a preset position in the long anchor cable hole; Inflate the airbag through the inflation and exhaust pipe. When the inflation pressure reaches the preset pressure, the airbag bulges to support the stop sponge plug. Inject grout into the long anchor cable hole through a grouting pipe, and stop grouting after cement slurry flows out of the exhaust pipe; After the grouting is completed for the first preset time, the gas in the airbag is discharged, and the airbag and the grouting pipe are recovered; After the grouting is completed for the second preset time, the long anchor cable tray and anchor are installed.

7. The long anchor cable anchoring method according to claim 6, characterized in that: After inserting the tube bundle into the insertion hole in the center of the grout-stopping sponge plug, the method further comprises: A fixing piece is used to bind the lower end of the outer wall of the grout-stopping sponge plug so as to fix the grout-stopping sponge plug and the tube bundle together.

8. The long anchor cable anchoring method according to claim 7, characterized in that: After the fixing member is used to bind the lower end of the outer wall of the grout-stopping sponge plug to fix the grout-stopping sponge plug and the tube bundle together, the method further includes: The gap between the tube bundle and the grout-stopping sponge plug is sealed with foam glue.

9. The long anchor cable anchoring method according to claim 6, characterized in that: After the airbag and the inflation and exhaust pipes are detachably bundled with the tube bundle and inserted into the long anchor cable hole at a preset position, the method further includes: A fixing wedge is used to fix the end of the long anchor cable hole.

10. The long anchor cable anchoring method according to claim 6, characterized in that: The grouting into the long anchor cable hole through the grouting pipe comprises: injecting cement slurry with a water-cement ratio of 0.4-0.8 into the long anchor cable hole through the grouting pipe.

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