A buffer reinforcing device for high-temperature burst impact of resin anchor rod

Abstract

The application belongs to the technical field of anchor rod equipment. In order to solve the problem that the pyrolysis of resin anchoring agent at high temperature leads to drilling explosion and anchoring failure, a buffer and reinforcement device for high-temperature burst impact of resin anchor rod is provided, which comprises an anchor rod, a first pressure relief mechanism, a second buffer mechanism and a third reinforcement mechanism. The two ends of the anchor rod are respectively sleeved with a limiting nut and a tray, and the inside is provided with the first pressure relief mechanism comprising a pressure relief channel and a plurality of pressure relief holes. The anchor rod is a hollow structure to form the pressure relief channel. The plurality of pressure relief holes are uniformly distributed on the second end of the anchor rod. The second buffer mechanism comprises a shock absorbing spring and a first shock absorbing washer sleeved on the anchor rod. The first shock absorbing washer is located between the shock absorbing spring and the tray. The third reinforcement mechanism comprises an anchor net arranged on the surface of the coal wall, a hollow disc and a cable connecting the anchor net and the hollow disc. The hollow disc is sleeved on the anchor rod and located between the limiting nut and the shock absorbing spring. The device realizes the step-by-step dissipation of energy through staged processing.

Description

Technical Field

[0001] This invention belongs to the technical field of anchor bolt equipment, and particularly relates to a buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts. Background Technology

[0002] Anchor bolts and cables are currently the most important roadway support technologies in my country's coal mines. Resin composite anchoring materials, due to their rapid gelation, high strength, and stable performance, are widely used in the reinforcement of geotechnical engineering projects such as coal mine roadways, mountain tunnels, and building structures. Coal mine resin anchoring materials are made from a mixture of unsaturated polyester resin, calcium carbonate powder, and a curing agent, belonging to organic polymer composite materials. However, improper manual operation, insufficient mixing of the anchoring agent, stress, and mine water corrosion can all lead to insufficient anchoring, thus affecting anchoring performance. Furthermore, unsaturated polyester resin undergoes pyrolysis at a certain temperature; at 350℃, it decomposes rapidly, producing a large amount of gas. This gas cannot penetrate the sealed anchor bolt borehole, and all the energy accumulates at the nozzle opening. Upon reaching a certain pressure, it bursts out of the nozzle opening, causing damage to the anchoring material and posing a significant threat to the safety of the engineering structure.

[0003] When a gas explosion occurs in a coal mine or a sudden fire breaks out on the ground or in a building, the temperature of the structure can reach 500℃ to 800℃. At this temperature, the resin anchoring material will pyrolyze, causing anchoring failure. An explosion may occur in the borehole, and the anchor rod may be ejected outwards due to the pyrolytic expansion of the resin anchoring material within the borehole, posing a significant threat to the stability and safety of the engineering structure. Existing buffering devices mostly use a single mechanical buffering method, without considering the need to reduce energy accumulation through pressure relief first, resulting in limited buffering efficiency. Therefore, a multi-stage device that first relieves pressure and then buffers is needed to ensure that some energy is released first in the event of an explosion, and then the remaining kinetic energy is absorbed by the mechanical structure, while simultaneously providing secondary reinforcement. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a buffering and reinforcement device for high-temperature bursting impact of resin anchor bolts, capable of multi-level synergistic and gradual dissipation of bursting energy.

[0005] This invention provides a buffering and reinforcement device for high-temperature bursting impact of resin anchor bolts, comprising:

[0006] An anchor bolt has a limit nut fitted on its upper part and a tray fitted on its middle and lower part. The anchor bolt has a first-stage pressure relief mechanism inside, which includes a pressure relief channel and multiple pressure relief holes. The anchor bolt has a hollow structure inside to form a pressure relief channel, and multiple pressure relief holes are evenly distributed in the lower part of the anchor bolt.

[0007] The secondary buffer mechanism includes a shock-absorbing spring and a first shock-absorbing washer. Both the shock-absorbing spring and the first shock-absorbing washer are sleeved on the anchor rod, and the first shock-absorbing washer is located between the shock-absorbing spring and the tray.

[0008] The three-stage reinforcement mechanism includes an anchor mesh, a cable, and a hollow disc. The anchor mesh is placed on the surface of the coal face, the hollow disc is fitted onto the anchor rod and located between the limit nut and the shock-absorbing spring, and the cable connects the anchor mesh and the hollow disc.

[0009] Optionally, all pressure relief holes are perpendicular to the pressure relief channel, with a diameter of 2.5 mm for the pressure relief holes and a diameter of 8 mm for the pressure relief channel.

[0010] The ratio of the cross-sectional area of ​​the pressure relief channel to the total flow area of ​​all pressure relief holes ranges from 1.2:1 to 1.5:1.

[0011] Optionally, the lower end of the shock-absorbing spring is in contact with the first damping washer, the inner diameter of the shock-absorbing spring is 1-2mm larger than the diameter of the anchor rod, the length of the shock-absorbing spring in the uncompressed state is 80-120mm, and the stiffness of the shock-absorbing spring is 2.0-3.0kN / mm.

[0012] Optionally, the secondary buffer mechanism also includes a second damping washer, a third damping washer, a first metal washer, and a second metal washer fitted onto the anchor bolt;

[0013] The first metal washer is placed between the shock-absorbing spring and the first damping washer; the second metal washer is placed at the upper end of the shock-absorbing spring; the second damping washer is placed between the second metal washer and the hollow disc; and the third damping washer is placed between the hollow disc and the limiting nut.

[0014] The first, second, and third damping washers, as well as the first and second metal washers, all have the same inner diameter. The outer diameters of the first, second, and third damping washers are 5-10 mm larger than those of the first and second metal washers. The outer diameters of the first and second metal washers are larger than the outer diameters of the damping springs.

[0015] Optionally, the hollow disc includes an upper disc and a lower disc spaced apart along the axis of the anchor rod. A through hole for the anchor rod to pass through is provided at the middle position of both the upper and lower discs. Two receiving grooves are provided on opposite sides of the upper and lower discs. The two receiving grooves located in the same plane are parallel and symmetrically arranged with respect to the axis of the anchor rod. Both ends of the four receiving grooves penetrate the circumferential sidewall of the corresponding upper or lower disc. The cable passes through the receiving groove along the through direction of the receiving groove.

[0016] The width of the receiving groove is the same as the diameter of the cable, and the depth of the receiving groove is 0.4-0.6 times the diameter of the cable.

[0017] Optionally, through slots are symmetrically arranged on the upper and lower discs, and temperature sensors are installed in the through slots to detect the temperature inside the anchor bolt borehole.

[0018] Optionally, the angle between the cable and the anchor bolt is less than or equal to 30°.

[0019] Optionally, the three-stage reinforcement mechanism also includes a locking mechanism, which includes a housing and a locking plate. The locking plate is disposed inside the housing, and the cable passes through the gap between the locking plates and is locked by bolts.

[0020] Optionally, a fastening nut is provided between the first shock-absorbing washer and the tray;

[0021] The thickness of the limiting nut is 1.2-1.5 times the thickness of the fastening nut.

[0022] The technical solution provided by the embodiments of the present invention has the following beneficial effects compared with the prior art:

[0023] This invention provides a buffering and reinforcement device for high-temperature bursting impact of resin anchor bolts. It employs a synergistic primary pressure relief mechanism, a secondary buffering mechanism, and a tertiary reinforcement mechanism. The primary pressure relief mechanism discharges high-pressure gas through pressure relief holes and channels, reducing initial energy. The secondary buffering mechanism, through the synergistic action of its damping springs and first shock-absorbing washers, absorbs remaining kinetic energy through friction and elastic deformation. Finally, the tertiary reinforcement mechanism, with its rigid connection between the cable, hollow disc, and anchor mesh, provides secondary reinforcement, ensuring the anchor bolt body will not be ejected. This three-tiered defense system progressively dissipates energy through graded treatment, enhancing the high-temperature burst resistance safety of the support system. It effectively solves the problem of anchor bolt bursting impact caused by the expansion and pyrolysis of resin anchoring agents at high temperatures, significantly improving the high-temperature safety redundancy of geotechnical engineering support systems. Furthermore, this buffering and reinforcement device for high-temperature bursting impact of resin anchor bolts is simple to assemble and disassemble, suitable for confined operating spaces. Installation can be completed using existing anchor bolt construction techniques, requiring no specialized equipment and resulting in low replacement costs. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1This is a schematic diagram of the structure of a buffer reinforcement device for high-temperature bursting impact of resin anchor bolts according to an embodiment of the present invention;

[0027] Figure 2 This is an exploded view of a buffer reinforcement device for high-temperature bursting impact of resin anchor bolts according to an embodiment of the present invention;

[0028] Figure 3 This is an exploded view of the hollow disk described in an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the upper disk structure according to an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the structure of the lower disk according to an embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of the primary pressure relief mechanism described in an embodiment of the present invention being installed in an anchor bolt;

[0032] Figure 7 This is a schematic diagram illustrating the installation steps of a buffer reinforcement device for high-temperature bursting impact of resin anchor bolts according to an embodiment of the present invention.

[0033] Figure 8 This is a schematic diagram showing the installation position of a buffer reinforcement device for high-temperature bursting impact of a resin anchor bolt, as described in an embodiment of the present invention.

[0034] The components include: 1. Anchor bolt; 2. Limiting nut; 3. First damping washer; 4. First metal washer; 5. Hollow disc; 6. Shock-absorbing spring; 7. Fastening nut; 8. Tray; 9. Cable; 10. Lock; 11. Through groove; 12. Pressure relief channel; 13. Pressure relief hole; 14. Anchor mesh; 15. Second damping washer; 16. Third damping washer; 17. Second metal washer; 18. Upper disc; 19. Lower disc; 20. Receiving groove. Detailed Implementation

[0035] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0037] Reference Figures 1 to 8As shown, this embodiment provides a buffering and reinforcement device for high-temperature bursting impact of resin anchor bolts, including anchor bolt 1, a primary pressure relief mechanism, a secondary buffering mechanism, and a tertiary reinforcement mechanism.

[0038] Reference Figure 6 As shown, the anchor rod 1 has a primary pressure relief mechanism inside, which includes a pressure relief channel 12 and multiple pressure relief holes 13. In this embodiment, there are six pressure relief holes 13. The anchor rod 1 has a hollow structure to form the pressure relief channel 12. The multiple pressure relief holes 13 are evenly distributed in the lower part of the anchor rod 1, which is the part that contacts the resin anchoring agent. The pressure relief holes 13 are located within 150mm of the bottom end of the anchor rod 1, and all six pressure relief holes 13 are perpendicular to the pressure relief channel 12. The diameter of the pressure relief hole 13 is 2.5mm. The pressure relief channel 12... The diameter is 8mm, and the ratio of the cross-sectional area of ​​the pressure relief channel 12 to the total flow area of ​​the six pressure relief holes 13 ranges from 1.2:1 to 1.5:1. This ensures that when the resin anchoring agent is pyrolyzed at high temperature and a large amount of gas is generated, the gas can smoothly enter the pressure relief channel 12 through the pressure relief holes 13, thus ensuring the efficiency and stability of pressure relief. When the gas enters the pressure relief channel 12 from the pressure relief holes 13, due to the reasonable flow area ratio, the gas will not form excessive resistance at the pressure relief holes 13, thereby avoiding the situation of the anchor rod 1 bursting due to pressure accumulation.

[0039] Reference Figure 1 and Figure 2 As shown, a limiting nut 2 is fitted onto the upper part of the anchor rod 1, and a tray 8 is fitted onto the lower middle part of the anchor rod 1. The secondary buffer mechanism includes a shock-absorbing spring 6 and a first shock-absorbing washer 3. Both the shock-absorbing spring 6 and the first shock-absorbing washer 3 are fitted onto the anchor rod 1, with the first shock-absorbing washer 3 located between the shock-absorbing spring 6 and the tray 8. The shock-absorbing spring 6 is made of spring steel, and its lower end is in contact with the first shock-absorbing washer 3. The inner diameter of the shock-absorbing spring 6 is 1-2 mm larger than the diameter of the anchor rod 1, thus ensuring that the shock-absorbing spring 6 can extend and retract along the axial direction of the anchor rod 1 without radial displacement. The length of the damping spring 6 in its uncompressed state ranges from 80 to 120 mm, and the stiffness of the damping spring 6 ranges from 2.0 to 3.0 kN / mm. Construction personnel can choose the appropriate damping spring 6 according to the expected impact force under different working conditions to meet different buffering requirements. When the anchor rod 1 is subjected to high-temperature bursting impact, the damping spring 6 first undergoes elastic deformation to absorb some of the impact energy and initially alleviate the impact force. The first damping washer 3 further plays a buffering role, avoiding direct rigid contact between the damping spring 6 and the tray 8, reducing the impact force damage to the tray 8, and ensuring a balance between buffering efficiency and structural stability.

[0040] Furthermore, the secondary buffer mechanism also includes a second damping washer 15, a third damping washer 16, a first metal washer 4, and a second metal washer 17 fitted onto the anchor rod 1. The first metal washer 4 is positioned between the shock-absorbing spring 6 and the first damping washer 3, and the second metal washer 17 is positioned at the upper end of the shock-absorbing spring 6. The first metal washer 4 and the second metal washer 17 have a positioning function for the shock-absorbing spring 6 and can transmit the elastic force of the shock-absorbing spring 6, making the force on the shock-absorbing spring 6 more uniform and improving the buffering effect. The second damping washer 15 is positioned between the second metal washer 17 and the hollow disc 5, and the third damping washer 16 is positioned between the hollow disc 5 and the limiting nut 2. The second damping washer 15 and the third damping washer 16 further buffer the impact force on the anchor rod 1, reduce damage to the hollow disc 5 and the limiting nut 2, and extend the service life of the device.

[0041] Specifically, the inner diameters of the first damping washer 3, the second damping washer 15, the third damping washer 16, the first metal washer 4, and the second metal washer 17 are all the same, and all are independently disassembled and replaceable components, improving the convenience of maintenance. The outer diameters of the first damping washer 3, the second damping washer 15, and the third damping washer 16 are 5-10mm larger than the outer diameters of the first metal washer 4 and the second metal washer 17. The outer diameters of the first metal washer 4 and the second metal washer 17 are larger than the radius of the damping spring 6. With this design, the first damping washer 3 can... The first metal washer 4 and its surrounding components are better covered and protected. The second shock-absorbing washer 15 can better cover and protect the second metal washer 17 and its surrounding components. The third shock-absorbing washer 16 can better cover and protect the hollow disc 5. At the same time, the elastic force of the shock-absorbing spring 6 can be effectively transmitted and dispersed. When the anchor rod 1 is impacted, the first shock-absorbing washer 3, the second shock-absorbing washer 15, the third shock-absorbing washer 16, the first metal washer 4, the second metal washer 17 and the shock-absorbing spring 6 can form a complete buffer system to gradually dissipate the burst impact force.

[0042] Among them, the first metal washer 4 and the second metal washer 17 are both made of stainless steel of grade no less than 316L, which has the properties of resisting high temperature above 800℃ and rust resistance in humid environments. The first damping washer 3, the second damping washer 15 and the third damping washer 16 are all graphite composite washers, and their materials have the properties of resisting high temperature above 800℃. Of course, the first damping washer 3, the second damping washer 15 and the third damping washer 16 can also be made of other high temperature resistant and corrosion resistant materials with damping effect.

[0043] A fastening nut 7 is provided between the first shock-absorbing washer 3 and the tray 8. The fastening nut 7 can further fix the tray 8 and prevent the tray 8 from shifting when it is impacted. The thickness of the limiting nut 2 is 1.2 to 1.5 times the thickness of the fastening nut 7, which can better limit the axial movement of the anchor rod 1 and improve the stability of the limit.

[0044] Continue to refer to Figure 1 and Figure 2 As shown, the three-stage reinforcement mechanism includes an anchor mesh 14, a cable 9, and a hollow disc 5. The anchor mesh 14 is set on the surface of the coal wall, and the hollow disc 5 is sleeved on the anchor rod 1 and located between the limiting nut 2 and the shock-absorbing spring 6. The cable 9 connects the anchor mesh 14 and the hollow disc 5. When the anchor rod 1 is subjected to high-temperature bursting impact, the anchor rod 1 drives the hollow disc 5 to slide along the axial direction of the anchor rod 1. The cable 9 connected to the hollow disc 5 can form a radial tensile constraint. The rigid connection between the cable 9 and the anchor mesh 14 restricts the displacement of the hollow disc 5 and the anchor rod 1, thereby forming a reinforcement defense line.

[0045] In this case, the angle between the cable 9 and the anchor 1 is less than or equal to 30°. At this angle, the axial component of the cable 9 along the axis of the anchor 1 is larger, which can maximize the use of the tensile strength of the cable 9 to hold the ejected anchor 1 and reduce the loss of impact energy transmission. At this angle, the radial component of the cable 9 perpendicular to the anchor 1 is smaller, which can avoid the risk of the anchor 1 bending or breaking due to excessive lateral force. Meanwhile, the cable 9 can be closer to the coal wall surface, which can quickly transfer the impact load of a single anchor 1 to the surrounding anchors 1 and anchor net 14, so that multiple anchors 1 and the entire anchor net 14 form a cooperative bearing network, avoiding isolated force when a single anchor 1 is impacted. Through the planar coverage of the anchor net 14 and the linear connection of the cable 9, the local impact load is dispersed to a larger area of ​​surrounding rock, which improves the overall support's resistance to collapse.

[0046] Reference Figure 3 , Figure 4 and Figure 5 As shown, the hollow disc 5 includes an upper disc 18 and a lower disc 19 spaced apart along the axial direction of the anchor rod 1. Both the upper disc 18 and the lower disc 19 have through holes at their midpoints for the anchor rod 1 to pass through. Two receiving grooves 20 are provided on opposite sides of the upper disc 18 and the lower disc 19. These two receiving grooves 20, located in the same plane, are parallel and symmetrically arranged relative to the axial direction of the anchor rod 1. Both ends of the four receiving grooves 20 penetrate the circumferential sidewall of the corresponding upper disc 18 or lower disc 19. The width of the receiving groove 20 is the same as the diameter of the cable 9, and the depth of the receiving groove 20 is 0.4-0.6 times the diameter of the cable 9. When the upper disc 18 and the lower disc 19 are tightened with bolts, the corresponding receiving grooves 20 of the upper disc 18 and the lower disc 19 merge to form a closed cable fixing cavity. The cable 9 can pass through the receiving groove 20 along its through-path, achieving a rigid connection between the cable 9 and the hollow disc 5.

[0047] Furthermore, through grooves 11 are symmetrically arranged on the upper disc 18 and the lower disc 19. Temperature sensors are installed in the through grooves 11 to detect the temperature inside the borehole of the anchor bolt 1. Specifically, the diameter of the through groove 11 is 8-12 mm. The temperature sensor is a K-type thermocouple with a measurement range of 0-1000℃ and an accuracy of ±1℃. The temperature sensor is connected to the monitoring center through an intrinsically safe IoT module in the well. The temperature threshold is set to 300℃, and the pyrolysis starting temperature of the resin anchoring agent is 350℃. When the temperature sensor detects that the temperature inside the anchor bolt borehole reaches the temperature threshold, the monitoring center issues an audible and visual alarm to remind the construction personnel to take timely measures to avoid the occurrence of an anchor bolt 1 bursting and impact accident caused by a large amount of gas generated by the pyrolysis of the resin anchoring agent.

[0048] The three-stage reinforcement mechanism also includes a locking buckle 10, which includes a housing and a locking plate. The locking plate is located inside the housing, and the cable 9 passes through the gap of the locking plate and is locked by bolts. The locking buckle 10 can ensure the stability of the connection between the cable 9 and the anchor net 14, and between the cable 9 and the hollow disc 5, and prevent the cable 9 from loosening or falling off when subjected to impact, thus ensuring the reliability of the entire three-stage reinforcement mechanism.

[0049] The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts provided in this embodiment of the invention achieves the function of multi-level coordinated gradual dissipation of bursting energy through the synergistic action of a primary pressure relief mechanism, a secondary buffer mechanism, and a tertiary reinforcement mechanism. When the resin anchoring agent undergoes high-temperature pyrolysis to generate high-pressure gas, the gas preferentially enters the pressure relief channel 12 through the pressure relief hole 13 at the bottom of the anchor rod 1, and is quickly discharged outside the borehole along the pressure relief channel 12, directly reducing the pressure peak inside the borehole and reducing energy accumulation from the source. If the remaining pressure inside the borehole still pushes the anchor rod 1 outward and tends to eject, the anchor rod 1 will squeeze the first damping washer 3 and the shock-absorbing spring 6 in sequence during its movement. The friction damping effect of the first damping washer 3 and the elastic deformation of the shock-absorbing spring 6 work together to absorb the kinetic energy of the anchor rod 1, achieving kinetic energy attenuation. When the anchor rod 1 drives the hollow disc 5 to slide along the axial direction of the anchor rod 1, the cable 9 and the anchor net 14 fixed to the hollow disc 5 form a radial tensile constraint. The rigid connection between the cable 9 and the anchor net 14 limits the displacement of the hollow disc 5 and the anchor rod 1, forming a reinforced defense line. The triple mechanism of first-level pressure relief, second-level buffering and third-level reinforcement ensures that the anchor rod 1 will not eject.

[0050] To ensure the safe installation of cable 9, the installation angle of cable 9 should be... It should meet the following requirements:

[0051]

[0052] In the formula: The actual angle between cable 9 and anchor bolt 1. The safe critical angle between cable 9 and anchor bolt 1. This represents the maximum force when anchor bolt 1 is ejected. The breaking tensile force of a single cable 9.

[0053] The length of cable 9 It should meet the following requirements:

[0054]

[0055] In the formula: This is the actual length of cable 9. It is recommended to select 1.5-2 times the actual length based on the specific circumstances. Length, This is the minimum calculated length of cable 9. The height from the bottom of the tray 8 to the top of the hollow disc 5 when the shock-absorbing spring 6 is fully relaxed. The diameter of the hollow disk 5 is given.

[0056] Before installing the buffer reinforcement device for the high-temperature bursting impact of this resin anchor bolt in the well, the installation angle and length of the cable 9 should be determined according to the above formula.

[0057] Reference Figure 7 and Figure 8As shown, the installation steps of the buffer reinforcement device for high-temperature bursting impact of this resin anchor are as follows: Before anchoring work in the well, the cable 9 and the hollow disc 5 are assembled in advance. The cable 9 is made of two stainless steel cables with a diameter of 6mm and a breaking tensile strength greater than or equal to 22kN, with a length of 1440mm. The hollow disc 5 is made of 316L stainless steel and consists of two identical upper discs 18 and 19. The dimensions of both upper disc 18 and lower disc 19 are φ100mm×15mm. The center of both upper disc 18 and lower disc 19 is machined with a through hole with a diameter of 21mm, which is slightly larger than the diameter of the anchor 1. The groove width of the receiving groove 20 is 6mm and the depth of the receiving groove 20 is 2.5mm. After inserting the two cables 9 into the receiving groove 20 respectively, the upper disc 18 and lower disc 19 are tightened and fixed with hexagonal bolts. According to the design... Based on the design requirements and construction drawings, determine the location of the anchor bolt drilling holes and mark the locations with a steel ruler or red paint. Use a pneumatic drill to drill the holes. After drilling, the hole depth should be between 3100-3150mm, the hole diameter at the opening should be between 50-45mm, and the hole diameter in the middle section of the rock mass should be 42mm. After drilling, use high-pressure air to blow out the rock debris and dust, clean the rock powder in the anchor bolt hole, and prevent debris from entering the anchor bolt hole and blocking the pressure relief channel 12. According to the resin anchoring agent model, quantity, and filling sequence specified in the design requirements, fill the resin anchoring agent into the anchor bolt hole in sequence. Select a 20mm×3200mm threaded steel anchor bolt 1. The center of the anchor bolt 1 is machined with a through-type φ8mm pressure relief channel 12. Six pressure relief holes 13 with a diameter of 2.5mm are evenly machined within a 150mm range of the lower part of the anchor bolt 1.

[0058] like Figure 7 As shown in (a), the tray 8 and the fastening nut 7 are installed sequentially from the lower middle to the upper part of the anchor rod 1. An MQT-130 / 3.2 type resin anchor rod installation machine is used to cover the upper end of the anchor rod 1, rotating it at 200 r / min and advancing the anchor rod 1 at a speed of 0.8 m / s until approximately 250 mm of the end of the anchor rod 1 protrudes. The resin anchoring agent is stirred using the anchor rod installation machine to ensure full contact and curing of the resin anchoring agent with the hole wall. Figure 7 As shown in (b), install the first damping washer 3, the first metal washer 4, the damping spring 6, the second metal washer 17, the second damping washer 15, the hollow disc 5, the third damping washer 16, and the limiting nut 2 in sequence. Tighten the limiting nut 2 to maintain the damping spring 6 with a pre-compression of 5mm. The length of the anchor rod 1 protruding from the limiting nut 2 is controlled to be 30mm ± 2mm to ensure the initial stability of the secondary buffer mechanism. After the resin anchoring agent solidifies, tighten the fastening nut 7 to ensure that the pre-tightening force of the anchor rod 1 meets the requirements. Figure 7As shown in (c), the anchor mesh 14 is finally laid, using low-carbon steel welded mesh with a diameter of 6mm. The mesh size of the anchor mesh 14 is 100mm × 100mm, and the overlap length of the mesh is 100mm. The two ends of the cable 9 are passed through the nodes of the anchor mesh 14; Figure 7 As shown in (d), the anchor bolt 1 is secured using a locking buckle 10, which is compatible with a 6mm diameter cable 9. After completing the above steps, the anchor bolt 1 is permanently supported.

[0059] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0060] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts, characterized in that, include: An anchor rod (1) is fitted with a limiting nut (2) on its upper part and a tray (8) on its middle and lower part. An anchor rod (1) is equipped with a first-level pressure relief mechanism, which includes a pressure relief channel (12) and multiple pressure relief holes (13). The anchor rod (1) is hollow to form a pressure relief channel (12). Multiple pressure relief holes (13) are evenly distributed in the lower part of the anchor rod (1). All pressure relief holes (13) are perpendicular to the pressure relief channel (12). The diameter of the pressure relief hole (13) is 2.5 mm and the diameter of the pressure relief channel (12) is 8 mm. The ratio of the cross-sectional area of ​​the pressure relief channel (12) to the total flow area of ​​all pressure relief holes (13) is 1.2:1 to 1.5:

1. The secondary buffer mechanism includes a shock-absorbing spring (6) and a first shock-absorbing washer (3). Both the shock-absorbing spring (6) and the first shock-absorbing washer (3) are sleeved on the anchor rod (1), and the first shock-absorbing washer (3) is located between the shock-absorbing spring (6) and the tray (8). The lower end of the shock-absorbing spring (6) is in contact with the first shock-absorbing washer (3). The inner diameter of the shock-absorbing spring (6) is 1-2 mm larger than the diameter of the anchor rod (1). The length of the shock-absorbing spring (6) in the uncompressed state is 80-120 mm. The stiffness of the shock-absorbing spring (6) is 2.0-3.0 kN / mm. The secondary buffer mechanism also includes a second damping washer (15), a third damping washer (16), a first metal washer (4), and a second metal washer (17) fitted on the anchor rod (1); the first metal washer (4) is located between the damping spring (6) and the first damping washer (3), the second metal washer (17) is located at the upper end of the damping spring (6), the second damping washer (15) is located between the second metal washer (17) and the hollow disc (5), and the third damping washer (16) is located between the hollow disc (5) and the limiting nut (2); The three-level reinforcement mechanism includes an anchor net (14), a cable (9) and a hollow disc (5). The anchor net (14) is set on the surface of the coal wall, and the hollow disc (5) is sleeved on the anchor rod (1) and located between the limit nut (2) and the shock-absorbing spring (6). The cable (9) connects the anchor net (14) and the hollow disc (5).

2. The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts according to claim 1, characterized in that, The inner diameters of the first damping washer (3), the second damping washer (15), the third damping washer (16), the first metal washer (4), and the second metal washer (17) are all the same. The outer diameters of the first damping washer (3), the second damping washer (15), and the third damping washer (16) are 5-10 mm larger than the outer diameters of the first metal washer (4) and the second metal washer (17). The outer diameters of the first metal washer (4) and the second metal washer (17) are larger than the outer diameter of the damping spring (6).

3. The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts according to claim 1, characterized in that, The hollow disc (5) includes an upper disc (18) and a lower disc (19) spaced apart along the axis of the anchor rod (1). The upper disc (18) and the lower disc (19) are both provided with through holes for the anchor rod (1) to pass through. The upper disc (18) and the lower disc (19) are each provided with two receiving grooves (20) on opposite sides. The two receiving grooves (20) located in the same plane are parallel and symmetrically arranged with respect to the axis of the anchor rod (1). The two ends of the four receiving grooves (20) are all connected to the circumferential sidewall of the corresponding upper disc (18) or lower disc (19). The cable (9) passes through the receiving groove (20) along the through direction of the receiving groove (20). The width of the receiving groove (20) is the same as the diameter of the cable (9), and the depth of the receiving groove (20) is 0.4-0.6 times the diameter of the cable (9).

4. The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts according to claim 3, characterized in that, A through groove (11) is symmetrically arranged on the upper disc (18) and the lower disc (19). A temperature sensor is installed in the through groove (11) to detect the temperature inside the borehole of the anchor rod (1).

5. The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts according to claim 1, characterized in that, The angle between the cable (9) and the anchor (1) is less than or equal to 30°.

6. The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts according to claim 1, characterized in that, The third-level reinforcement mechanism also includes a lock (10), which includes a housing and a locking plate. The locking plate is located inside the housing, and the cable (9) passes through the gap between the locking plates and is locked by bolts.

7. The buffer and reinforcement device for high-temperature bursting impact of resin anchor bolts according to claim 1, characterized in that, A fastening nut (7) is provided between the first shock-absorbing washer (3) and the tray (8); The thickness of the limiting nut (2) is 1.2-1.5 times the thickness of the fastening nut (7).

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