High-strength high-impact-energy stress display abdicating anchor rod

Abstract

The invention relates to a high-strength high-impact-energy stress display abdicating anchor rod which comprises an anchor rod body, one end of the anchor rod body is provided with threads and is a threaded part, the anchor rod further comprises a tray which is perpendicular to the axial direction of the anchor rod body and is arranged in the middle of the anchor rod body, and the middle of the anchor rod body is provided with a through hole for the anchor rod body to be connected in an inserted mode; one end of the thread part on the anchor rod body is sleeved with the energy-releasing yielding pipe, one end of the inner wall of the energy-releasing yielding pipe is provided with homodromous threads matched with the thread part on the anchor rod body, and the inner diameter of the end, without threads, of the energy-releasing yielding pipe is larger than that of the other end of the energy-releasing yielding pipe; the damping nut is in threaded connection with the end part of the threaded part of the anchor rod body, abuts against the end part of the energy-releasing yielding pipe and extrudes the energy-releasing yielding pipe to a bent state; and the anti-drag gasket system is arranged at the part, between the energy-releasing yielding pipe and the tray, of the threaded part of the anchor rod body. The method has the advantages that the process of measuring the stress borne by the anchor rod is simplified, and the stress borne by the anchor rod is visualized.

Description

Technical Field

[0001] This application relates to the field of bolt support technology, and particularly to a high-strength and high-impact-work stress-displaying yielding bolt. Background Art

[0002] In mines or quarries where ore or other resources need to be mined underground, the construction of underground caves needs to be carried out first. The construction process is briefly described as follows. First, technicians clean the surface of the ground or the side wall of the mountain rock and remove the vegetation. Then, drilling technology is used to mine the ore. As the project progresses, an underground cave will be formed at the construction site.

[0003] During the construction process, the part of the rock mass close to the cave wall is affected by the blasting construction of the working layer, forming an unstable rock fracture layer that wraps the construction cave. Its structural strength is relatively low, and the blasting impact is likely to cause the collapse of the cave rock fracture layer, resulting in mine accidents. Therefore, it is necessary to support the mine cave.

[0004] Bolt support is a common underground engineering support technology used to enhance the stability of soil or rock mass and prevent rock layers from sliding and falling off. It is fixed in the surrounding rock fracture layer of the underground project through materials such as steel bars or steel cables. The specific construction method is as follows. First, technicians inject a vitreous body filled with high-strength gel into the pre-drilled holes, then drive the steel bars or steel cables into the holes to crush the vitreous body, release the gel and quickly solidify it. Utilize the friction of the soil and the adhesiveness of the high-strength gel to combine the steel bars with the soil as a whole, and then install and fix a protective device on the bolt to restrict the deformation of the soil or rock mass, reduce the possibility of settlement and collapse of the underground project, and ensure the safety and stability of the project.

[0005] The bolts installed on the top wall of the mine cave form an integral whole with the surrounding rock mass, reducing the possibility of collapse by increasing the structural strength of the outer rock mass of the mine cave. Before the rock on the cave top collapses, the bolts need to be axially broken along the bolts first. However, the axial stress borne by the bolts is still large but there is still a safety limit, and they have a certain service life. As the service life approaches, their stress-bearing performance will decrease, and technicians need to regularly measure the bearing stress of the bolts and calculate whether there is a possibility of collapse of the rock mass at the fixed points.

[0006] The existing bolt stress measurement requires technicians to regularly use a torque wrench for detection, and multiple bolts need to be detected in sequence. This method cannot adapt to mine caves with a large number of installed bolts. For the above related technologies, the bolt structure can be improved to make the stress-bearing effect intuitive. Summary of the Invention

[0007] In order to simplify the bolt stress measurement process and make the bolt stress performance intuitive, the present invention provides a high-strength and high-impact-work stress-displaying yielding bolt.

[0008] The high-strength and high-impact-work stress-displaying yielding bolt provided by the present invention adopts the following technical solution: A high-strength and high-impact-work stress-displaying yielding bolt, comprising a bolt rod body, one end of the bolt rod body is provided with threads, which is a threaded portion, and is characterized in that it further comprises; A tray, perpendicular to the axial direction of the bolt rod body and arranged in the middle part of the bolt rod body, and a through hole for inserting the bolt rod body is opened in the middle part; An energy-releasing and pressure-yielding tube, sleeved on one end of the threaded portion of the bolt rod body, and one end of the inner wall is provided with the same-direction threads adapted to the threaded portion on the bolt rod body, and the inner diameter of the end without threads is larger than that of the other end. When the energy-releasing and pressure-yielding tube is threadedly connected to the bolt rod body, the other end is a free end; A damping nut, threadedly connected to the end of the threaded portion of the bolt rod body, abuts against the end of the energy-releasing and pressure-yielding tube, and squeezes the energy-releasing and pressure-yielding tube into a bent state; A drag-reducing washer system, arranged on the part of the threaded portion of the bolt rod body between the energy-releasing and pressure-yielding tube and the tray.

[0009] By adopting the above technical solution, the bolt body serves as the main part of the bolt, and the tray, energy-releasing yielding pipe, damping nut, and friction-reducing washer system are all distributed axially along the bolt body as accessory structures; technicians pre-drill holes at fixed points in the mine tunnel, then insert glass tubes filled with gel and fix them at the bottom of the holes, and then drive the non-threaded part of the bolt body of the bolt into the holes, contacting the tube body of the glass tube and applying pressure to crush it, so that the gel contained in the glass tube scatters into the holes, contacts the air and solidifies, making the non-threaded end of the bolt body integrated with the rock through the adhesive force of the gel and the frictional force, enhancing the stability of the soil or rock mass, thereby preventing the collapse of the mine tunnel in underground engineering and the collapse of the rock on the tunnel wall, and improving the engineering safety; it should be noted that the insertion depth of the bolt body should penetrate the unstable rock fracture layer to fix the entire fracture layer with a greater collapse risk and the rock mass above; based on the insertion of the bolt, one side of the tray abuts against the inner top wall of the mine tunnel, and the trays of multiple bolts form the main body for supporting the stability of the tunnel wall. The bottom side of the tray is supported by the energy-releasing yielding pipe. One end of the energy-releasing yielding pipe away from the tray is tightened and supported by the damping nut, and its end close to the tray is also threadedly connected to the bolt. The tray is supported through the structure, and the damping nut is also supported through the threaded connection adapting to the threaded part of the bolt body. Based on the positional relationship among the three, a friction-reducing washer system is arranged between the energy-releasing yielding pipe and the tray to form a "sandwich" assembly structure; in the above solution, the friction-reducing washer system includes an elastic component with a certain thickness, which deforms under the extrusion of torque, and then converts part of the installation torque into radial installation stress, sharing the circumferential force received by the bolt and strengthening the structural strength of the bolt. In addition, the elastic component can provide additional friction and resistance; it should be noted that after the technician installs the energy-releasing yielding pipe, first threadedly connect the threaded end of the energy-releasing yielding pipe to the bolt body and abut against the friction-reducing washer system. At this time, the other end of the energy-releasing yielding pipe is a free end, and there is a gap between its inner wall and the threaded part of the bolt body. Then the technician installs the damping nut, making one end of the damping nut abut against the end of the free end of the energy-releasing yielding pipe. The technician tightens the damping nut with a pneumatic wrench, so that the damping nut squeezes the free end of the energy-releasing yielding pipe until the middle part of the energy-releasing yielding pipe bends outward. Thus, when there is a tendency of the rock mass on the top wall of the mine tunnel to collapse and squeezes the tray, ensuring that the energy-releasing yielding pipe bends outward when the tray transmits the extrusion stress to the energy-releasing yielding pipe, and the positive bending can ensure the structural strength of the bolt body and withstand a greater extrusion stress; in addition, the technician should pay attention to the distribution of the friction-reducing washer system between the tray and the energy-releasing yielding pipe during installation to ensure the force transmission path between the tray and the energy-releasing yielding pipe.

[0010] Optionally, it further includes; A shrinkable hose clamp, sleeved on the middle part of the energy-releasing yielding pipe, and its inner ring diameter is equal to the outer diameter of the bent part of the energy-releasing yielding pipe; A ring groove, opened in the middle part of the outer wall of the energy-releasing yielding pipe, for positioning the shrinkable hose clamp.

[0011] By adopting the above technical solutions, it is convenient for technicians to determine the standard expansion value. After the energy-releasing pressure-relieving pipe is installed, the technician first sleeved the corresponding shrinkage throat hoop around the corresponding annular groove of the energy-releasing pressure-relieving pipe, and then the technician screwed the damping nut with a pneumatic wrench. By abutting and squeezing the energy-releasing pressure-relieving pipe with the damping nut, the part of the energy-releasing pressure-relieving pipe corresponding to the annular groove expands until the bottom wall of the annular groove on the outer wall of the energy-releasing pressure-relieving pipe abuts against the inner wall of the shrinkage throat hoop. The technician stops the operation of the pneumatic wrench. When the bolt bears normal stress, the shrinkage throat hoop is clamped in the annular groove; when there is a tendency of rock mass fracture and collapse, the rock mass abuts against and squeezes the tray, and the tray transfers the squeezing stress to the energy-releasing pressure-relieving pipe and squeezes the energy-releasing pressure-relieving pipe to deform. The part corresponding to the shrinkage throat hoop in the middle expands, generating an expansion tendency from the inside of the shrinkage throat hoop, driving the guide plate of the shrinkage throat hoop to displace on the guide bolt of the shrinkage throat hoop. Thus, the technician can directly observe the positional relationship between the guide plate on the shrinkage throat hoop and the guide bolt to judge whether the stress borne by the energy-releasing pressure-relieving pipe at this time exceeds the safety value; In summary, the functions of the shrinkage throat hoop are as follows. First, the technician pre-sets the size of the shrinkage throat hoop to conform to the size of the middle bent part of the energy-releasing pressure-relieving pipe in the qualified installation state, restricting the bending deformation of the energy-releasing pressure-relieving pipe, and avoiding the technician over-screwing the damping nut with a pneumatic wrench, resulting in excessive deformation of the energy-releasing pressure-relieving pipe, and further resulting in the displacement distance of the energy-releasing pressure-relieving pipe when the rock on the top wall of the mine cave collapses; Second, the restriction of the shrinkage throat hoop on the energy-releasing pressure-relieving pipe enables the staff to directly observe the stress-bearing degree of the energy-releasing pressure-relieving pipe. When the guide plate of the shrinkage throat hoop does not exceed the safety line pre-marked by the technician on the guide bolt of the shrinkage throat hoop, it is a safe state. After the guide plate exceeds the safety line marked by the shrinkage throat hoop on the guide bolt, the technician should immediately reinforce the area around the bolt body to prevent the safety accident of the collapse of the top wall of the mine cave.

[0012] Optionally, the drag-reducing washer system includes; A spherical washer, adapted to the bolt body and arranged on the part of the bolt body close to the tray. One side of the spherical washer close to the tray is hemispherical. Correspondingly, a through hole is opened in the middle part of the tray and a hemispherical groove adapted to the spherical washer is provided.

[0013] By adopting the above technical solution, the setting of the spherical pad enables the tray surface to form an arbitrary acute angle with the axis of the bolt, improving the flexibility of the tray surface. Due to the limitations of the actual situation, the top of the mine cave is not flat. In most cases, it is difficult for the tray to ensure being completely perpendicular to the axis direction of the bolt. Based on this, the above solution appropriately enlarges the perforation in the middle part of the tray, so that there is a certain displaceability between the bolt and the perforation. A hemispherical spherical pad is provided at the bottom end of the tray, and the part of the perforation close to the spherical pad is polished into a hemispherical concave surface to make the perforation fit the spherical pad. When the tray tilts, the spherical pad and the perforation can flexibly contact at an arbitrary acute angle and ensure the positive transmission of stress. In summary, the hemispherical setting of the spherical pad and the tray corresponding to the spherical pad can improve the flexibility of the bolt during the bolt support process.

[0014] Optionally, the drag reduction washer system further includes; A steel washer, arranged between the spherical pad and the energy-releasing and pressure-relieving pipe, for transmitting stress; A drag reduction washer, inserted between the corresponding part of the bolt body of the washer and the steel washer, for buffering the extrusion tendency of the tray.

[0015] By adopting the above technical solution, the soft drag reduction washer is used as the main structure in the drag reduction washer system. When the rock mass has a tendency to collapse, the rock mass exerts a huge stress on the tray. The spherical pad converts the stress into an axial force along the bolt, resulting in a certain torque generated by the steel washer and the drag reduction washer around the thread. In addition to playing a role in reducing pressure, the soft drag reduction washer can also be deformed under the action of the torque, absorbing the energy of the torque and transferring it to the elastic deformation of the drag reduction washer, generating radial stress; in addition, the spherical pad ensures the force transmission path at an arbitrary acute angle. However, relying only on the rigid structure of the spherical pad to transfer the extrusion stress to the energy-releasing and pressure-relieving pipe, when directly contacting the end of the energy-releasing and pressure-relieving pipe on the flat side of the spherical pad, the huge stress is likely to cause the perforation on the tray to over-contact the hemispherical part of the spherical pad, thereby damaging the hemispherical structure of the spherical pad and making the bolt bear a huge non-axial stress. Therefore, a steel washer is arranged between the spherical pad and the energy-releasing and pressure-relieving pipe to increase the contact area between the spherical pad and the end of the energy-releasing and pressure-relieving pipe, and increase the maximum force value for damaging the hemispherical structure of the spherical pad.

[0016] Optionally, the middle part of the side of the tray close to the spherical pad is bent and protrudes from the tray surface.

[0017] By adopting the above technical solution, considering that the square tray is in the shape of a square plate as a whole, when the trend of rock mass collapse is located at the bearing edge of the tray, the narrow and flat structure of the tray is difficult to bear huge stress, which easily leads to the deformation of the tray and then causes the bolt to lose the bearing capacity for the surrounding rocks. Based on this, the middle part of the bottom end of the tray is set as a curved arc surface structure protruding from the tray surface, making the cross-section of the tray non-uniform. When the tray bears huge stress, the curved arc part in the middle can concentrate the stress received by the tray and share the huge stress borne by the four side edges of the tray, thereby protecting the structure at the side of the tray; In summary, by bending the middle part of the square tray, the stiffness and strength of the tray are increased by increasing the plate area and moment of inertia.

[0018] Optionally, it further includes; Connecting arms, one is provided at each corner of the tray and extends in a direction away from the tray; Connecting rings, fixedly connected to the end of each connecting arm away from the tray, and the ring surface is perpendicular to the tray surface. The connecting rings on different trays can be inserted into a whole by steel bolts.

[0019] By adopting the above technical solution, based on the bearing structure of the tray, connecting rings are extended at the four corners of the trays of multiple bolts, and the tray surfaces of multiple trays can be formed into a whole through the connecting rings, completing the combination of multiple areas in the mine cave into a whole, or the integration of multiple fixed points in one area; After a technician inserts a bolt at a pre-measured fixed point, calculates and finds other fixed points in the surrounding area near this bolt, and forms the split rock masses in the adjacent area into a whole, so that the stress of multiple split rocks with a tendency to collapse in the rock fracture layer is internally digested, enhancing the rock mass structure strength at the top of the mine cave; In summary, by connecting multiple trays through the connecting rings, multiple bolts are formed into the same whole, so as to make up for the deficiency of the bolt fixing area, and the rock layers in the same area are formed into a whole through multiple connected bolts, thereby ensuring the rock layer structure strength in a larger area.

[0020] Optionally, one end of the connecting arm is bolted to the tray to adjust the orientation of the connecting arm.

[0021] By adopting the above technical solution, considering that the cave wall is an irregular curved surface with unevenness in actual application, although it can meet the flat laying and expansion of a relatively small area such as the tray, it is difficult for the four connecting arms extending along the plane of the tray to meet the curved surface of the cave wall. Therefore, the four connecting arms extending from the tray can rotate around the tray at any flexible angle. After the technician installs the bolt, when forming the tray and other trays into the same whole through the connecting ring, loosen the bolt, adjust the multiple connecting arms to the corresponding angles and then tighten the bolt, align the corresponding connecting rings and insert the steel bolt into the connecting ring to form the same whole. The above solution improves the flexibility of the tray.

[0022] Optionally, both the ball pad and the damping nut are made of 45# steel; The material of the drag reduction washer is made of natural rubber.

[0023] By adopting the above technical solution, the materials of the ball pad and the damping nut are made of the common engineering structural steel - 45# steel. The main reason is that 45# steel has a relatively high yield strength and tensile strength, can withstand large external loads and axial tensile stresses, and is suitable for the application scenario of mine tunnel support. In addition, 45# steel has relatively high hardness and wear resistance, and can withstand the large frictional force between the rock mass structure and external construction; in the above solution, the advantage of using natural rubber for the drag reduction washer is that natural rubber has excellent elasticity and good fatigue resistance, and can maintain stable performance under long-term high-intensity pressure, and is suitable for the application scenario of deformation and distortion under the condition of bolt compression. In addition, natural rubber has excellent tear resistance, making the drag reduction washer have qualified structural strength.

[0024] In summary, the present application includes at least the following beneficial technical effects: 1. An energy-releasing pressure-relieving pipe for pressure relief is added between the tray and the end fixing part of the bolt support with a traditional structure. When the tray on the bolt bears huge stress, the tray transfers the axial stress of the bolt to the energy-releasing pressure-relieving pipe, and by compressing the middle cavity of the energy-releasing pressure-relieving pipe, the stress generated by the huge load of bolt fracture is buffered based on the pressure-relieving distance before bolt fracture, and the maximum value of bolt bearing pressure is increased; 2. The hemispherical perforations opened in the ball grooves corresponding to the ball grooves of the tray can enable the tray to flexibly adjust the angle according to actual applications. Since the mine tunnel wall is not an ideal plane, when the tray is inclined to the axial direction of the bolt, it can provide a stress transfer path between the tray and the bolt.

[0025] 3. The connecting ring provides the connection between adjacent trays, making multiple bolts form an integral whole, and can combine multiple rock masses with a tendency to collapse at single points in the rock fracture layer, so that the collapse stresses are mutually digested and offset inside the rock layer, thereby reducing the support burden of the bolts and further enhancing the structural strength of the rock mass. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure after installation of the embodiment of the present application.

[0027] Figure 2 It is an exploded view made to highlight the structures on the bolt body in the embodiment of the present application.

[0028] Figure 3 It is a schematic diagram of the structure of the energy-releasing pressure-relieving pipe before installing the damping nut in the embodiment of the present application to highlight it.

[0029] Figure 4This is a schematic structural diagram of the shrinkable throat hoop in the embodiments of the present application.

[0030] Explanation of reference numerals: 1. Anchor rod body; 11. Threaded part; 12. Energy-releasing and yielding pipe; 13. Damping nut; 14. Shrinkable throat hoop; 141. Guide plate; 142. Guide bolt; 2. Tray; 21. Perforation; 22. Bending part; 23. Connecting arm; 24. Connecting ring; 3. Drag-reducing washer system; 31. Ball pad; 32. Drag-reducing washer; 33. Iron washer. Detailed implementation manners

[0031] The following will Figures 1-4 further elaborate on the present application in detail.

[0032] The embodiments of the present application disclose a high-strength and high-impact work stress-displaying and yielding anchor rod body 1. Referring to Figure 1 , a high-strength and high-impact work stress-displaying and yielding anchor rod body 1 includes a long cylindrical anchor rod body 1. One end of the anchor rod body 1 is provided with a thread, which is the threaded part 11; anti-abrasion patterns are provided on the anchor rod body 1 (a common structure, not shown in the figure for the convenience of showing the rod body). In actual application, technicians pre-measure, calculate and mark the fixed points on the mine tunnel wall, drill deep holes through the rock fracture layers around the tunnel wall at the fixed points on the tunnel wall, then inject a glass bottle filled with gel into the deep holes, and drive the anchor rod body 1 in this embodiment into the deep holes and crush the glass bottles filled inside, releasing the gel contained in the glass bottles. The gel solidifies when encountering air, and with the friction of the tunnel wall in the deep holes, the end of the anchor rod body 1 without the thread is bonded in the hole,

[0033] Referring to Figure 1 and Figure 2 , on the premise that the anchor rod body 1 is fixed, a tray 2 is penetrated in an ideal state perpendicular to the axial direction of the anchor rod body 1. The tray 2 is in the shape of a square plate. A perforation 21 for the anchor rod body 1 to penetrate is provided in the middle part of the tray 2. The diameter of the perforation 21 is larger than the diameter of the anchor rod body 1, so that when the anchor rod body 1 is inserted into the tray 2, the tray 2 has a space for free movement relative to the anchor rod body 1. A fixing device for fixing the tray 2 is provided on the anchor rod body 1 to improve the stability of the tray 2; after the technicians install the anchor rod body 1, the tray 2 is fixed through the fixing device to abut against the rock layer of the mine tunnel roof. The tray 2 serves as the main framework for supporting the rock mass, and transfers the huge load generated by the rock blocks with a tendency to crack near the anchor rod body 1 to the corresponding structure at the end of the anchor rod body 1.

[0034] Referring to Figure 2 and Figure 3, in the embodiment of the present application, an energy - releasing and yielding pipe 12 is thread - connected to one end of the bolt body 1 close to the threaded portion 11. One end of the inner wall of the energy - releasing and yielding pipe 12 is provided with a thread adapted to the threaded portion 11 of the bolt body 1. The inner diameter of the other end of the energy - releasing and yielding pipe 12 is larger than that of the end where the thread is provided. When the energy - releasing and yielding pipe 12 is thread - connected to the bolt body 1, there is a gap between the inner wall of its end without thread and the thread teeth of the bolt body 1, forming a free end.

[0035] Refer to Figure 2 And Figure 3 , a damping nut 13 is thread - connected to the end of the bolt body 1 close to the threaded portion 11. The inner diameter of the damping nut 13 is provided with a thread adapted to the threaded portion 11 of the bolt body 1. The technician tightens the damping nut 13 so that the side wall of the damping nut 13 abuts against one end of the energy - releasing and yielding pipe 12. Then the technician continues to tighten the damping nut 13 with a pneumatic wrench so that the damping nut 13 squeezes one end of the energy - releasing and yielding pipe 12 until the middle part of the energy - releasing and yielding pipe 12 is significantly bent, and the connection between the damping nut 13 and the energy - releasing and yielding pipe 12 is completed.

[0036] After the tray 2 reaches the bearing limit, the energy - releasing and yielding pipe 12 has a certain yielding distance, reducing the axial tearing force borne by the bolt body 1. When the rock mass supported by the tray 2 has a tearing tendency, the tray 2 is pressed down, transmitting a huge load to the tray 2. The tray 2 squeezes the energy - releasing and yielding pipe 12. Since the damping nut 13 has squeezed the energy - releasing and yielding pipe 12 into a middle - bent part 22 during installation, the huge pressure transmitted by the tray 2 makes the energy - releasing and yielding pipe 12 increase its bending state. The bending deformation amount of the energy - releasing and yielding pipe 12 is the yielding distance. Within the safe range, the yielding deformation of the energy - releasing and yielding pipe 12 can relieve the huge load approaching the limit value of the adjacent bolt body 1. In summary, the energy - releasing and yielding pipe 12 is equivalent to a safety device. Before the load from the rock mass damages the bolt body 1, that is, before a safety accident occurs, the energy - releasing and yielding pipe 12 must be damaged in advance. When the energy - releasing and yielding pipe 12 bears a huge load, it deforms, and the technician can observe whether the energy - releasing and yielding pipe 12 deforms to judge whether it is necessary to process the rock mass fracture layer at this time.

[0037] Refer to Figure 2 , in the embodiment of the present application, a friction - reducing washer system 3 is arranged between the energy - releasing and yielding pipe 12 and the tray 2. The friction - reducing washer system 3 includes a hemispherical ball pad 31, an iron washer 33 and a friction - reducing washer 32 arranged between the two. The iron washer 33 and the friction - reducing washer are sequentially inserted on the bolt body 1, and the ball pad 31 is thread - connected to the bolt body 1.

[0038] Refer to Figure 2, the hemispherical ball pad 31 of the drag reduction washer system 3 is arranged close to the tray 2, and the spherical end of the ball pad 31 faces the direction close to the tray 2. Correspondingly, the part of the perforation 21 on the tray 2 corresponding to the ball pad 31 is semi-circular to adapt to the hemispherical surface of the ball pad 31. The structural setting of the hemispherical surface of the ball pad 31 can meet the requirement that the axial directions of the tray 2 and the bolt rod body 1 are set at any acute angle and transfer stress normally. In practical applications, since the mine wall is not an ideal plane, the tray 2 often needs to be rotated by a certain angle to reach the most suitable support angle. To achieve normal force transfer when the plane of the tray 2 is not perpendicular to the axial direction of the bolt rod body 1, the structure of a hemispherical cross-section is set using the principle of spherical hinge to cooperate with the tray 2, turning the huge pressure from the tray 2 at any angle into the axial force along the bolt rod body 1.

[0039] It should be noted that since the ball pad 31 plays a role in changing the direction of force transfer, in this embodiment, the ball pad 31 is cast from 45# steel. Since 45# steel has a relatively high yield strength and tensile strength, it can withstand large external loads and stresses, and is suitable for the usage scenario of the bolt rod body 1 that needs to transfer axial force. Additionally, in this embodiment, the damping nut 13 also uses 45# steel. The damping nut 13 has relatively high hardness and wear resistance, and can resist wear and friction. When the damping nut 13 abuts against the end of the energy-releasing and pressure-relieving tube 12 and rotates and extrudes, it can withstand great frictional losses.

[0040] Refer to Figure 2 , in this embodiment, the drag reduction washer 32 is made of natural rubber. The soft drag reduction washer 32 can deform when contacting the ball pad 31, converting the installation torque generated by the ball pad 31 along the thread into installation stress. Natural rubber has excellent fatigue resistance and wear resistance, can resist friction and wear, and can maintain stable performance under long-term stress extrusion. Based on this, when the drag reduction washer 32 undergoes extrusion deformation, the energy generated by the torque is transferred to the elastic deformation of the drag reduction washer 32, thereby generating radial stress, reducing the off-axis forces in other directions borne by the bolt rod body 1, and reducing the structural strength of the bolt rod body 1.

[0041] Refer to Figure 2 , in this embodiment, the diameter of the iron washer 33 is larger than the diameter of the uncompressed drag reduction washer 32. The iron washer 33 is provided to increase the contact area between the energy-releasing and pressure-relieving tube 12 and the drag reduction washer 32. After the drag reduction washer 32 is compressed and deformed under great stress, the cross-sectional area of the drag reduction washer 32 expands. To ensure normal stress transfer on the bolt rod body 1, an iron washer 33 with a diameter larger than the original size of the drag reduction washer 32 is set to ensure that the maximum deformation of the drag reduction washer 32 does not exceed the surface of the iron washer 33.

[0042] Refer to Figure 2, based on the above drag reduction washer system 3, in this embodiment, a bending portion 22 is provided on one side of the tray 2 close to the ball pad 31. The bending portion 22 is integrally in the shape of an arc surface protruding from the surface of the tray 2 towards the ball pad 31, and the perforation 21 starts in the middle part of the bending portion 22. The key point of this embodiment with a protruding portion provided in the middle of the tray 2 is to increase the disk area of the tray 2 and make the increased area non-uniform. When a huge stress acts on the tray 2, the bending portion 22 in the middle of the tray 2 bears a greater stress. By increasing the thickness of the middle part of the tray 2, the bending strength of the surface of the tray 2 is increased. Additionally, the bending portion 22 can also reduce the area of the weak part of the tray 2. When the edge of the tray 2 is subjected to the oppression of a huge stress, the surface arc structure of the bending portion 22 can provide a supporting effect on the side of the tray 2, making it difficult for the tray 2 to be bent.

[0043] Referring to Figure 2 and Figure 3 , considering that technicians tighten the damping bolt 13 with a pneumatic wrench, due to the strong effect of the pneumatic wrench, technicians cannot immediately perceive the extrusion situation of the damping bolt 13 on the energy-releasing pressure-relieving pipe 12. Without restrictions and standards, it is easy to overact. Therefore, in this embodiment, a shrinkage throat hoop 14 is sleeved on the middle bending portion 22 of the energy-releasing pressure-relieving pipe 12, and a ring groove for accommodating the shrinkage throat hoop 14 is correspondingly provided on the shrinkage throat hoop 14 to clamp and receive the shrinkage throat hoop 14 and prevent the shrinkage throat hoop 14 from axially moving.

[0044] Referring to Figure 3 and Figure 4 , in this embodiment, the shrinkage throat hoop 14 is composed of two circles of metal rings and two guiding plates 141 fixedly connected to the same ends of the two circles of metal rings. A guiding bolt 142 perpendicular to the plate surface of the guiding plates 141 is simultaneously threadedly connected to the two guiding plates 141. As the inner diameter of the shrinkage throat hoop 14 expands, the distance between the two guiding plates 141 on the guiding bolt 142 decreases until the two guiding plates 141 are in contact, and the inner diameter of the shrinkage throat hoop 14 cannot continue to expand. Based on this principle, when installing the bolt body 1 of the present application embodiment, the shrinkage throat hoop 14 needs to be sleeved in the ring groove corresponding to the energy-releasing pressure-relieving pipe 12 in advance. At this time, the outer diameter of the energy-releasing pressure-relieving pipe 12 is smaller than the inner diameter of the shrinkage throat hoop 14. Then, the technician tightens the damping bolt 13 with a pneumatic wrench to squeeze the energy-releasing pressure-relieving pipe 12, causing the middle part of the energy-releasing pressure-relieving pipe 12 to bend and its diameter to increase until the outer diameter of the energy-releasing pressure-relieving pipe 12 abuts against the inner diameter of the shrinkage throat hoop 14, and the technician stops the operation of the pneumatic wrench. That is, the shrinkage throat hoop 14 can give the technician a tightening standard.

[0045] Referring to Figure 1 and Figure 3, under the normal working state of the anchor rod body 1, the shrinkage throat hoop 14 is sleeved in the annular groove of the energy-releasing and pressure-relieving pipe 12. When the rock fracture layer collapses, the energy-releasing and pressure-relieving pipe 12 is extruded by the tray 2, causing the energy-releasing and pressure-relieving pipe 12 to expand. Excessive abnormal expansion will cause damage to the shrinkage throat hoop 14 sleeved on the outer wall. Technicians can judge whether reinforcement is needed by observing whether the shrinkage throat hoop 14 is damaged. In addition, since the expansion of the shrinkage throat hoop 14 can cause the distance between the two guide plates 141 at both ends to be pulled in, technicians can pre-calculate the safe pulling-in limit and directly observe the direct stress condition of the anchor rod body 1 with the naked eye.

[0046] Look back Figure 1 And Figure 2 , a connecting arm 23 is bolted at each of the four corners of the tray 2. The end of the connecting arm 23 is disc-shaped. A connecting hole is vertically penetrated through the end of the connecting arm 23 perpendicular to the disk surface of the tray 2, making the end of the connecting arm 23 annular, which is the connecting ring 24. The connecting ring 24 is used for the connection between the trays 2 on different anchor rod bodies 1. Technicians align the connecting rings 24 of the trays 2 on different anchor rod bodies 1 through the connecting arms 23 and insert a fixing bolt at the same time, so that multiple anchor rod bodies 1 form a whole, thereby making the multiple rock fracture regions around the mine tunnel integrated. The connection of multiple anchor rod bodies 1 enables the internal digestion of the huge stress generated by their collapse.

[0047] Based on the above structure, the necessity of bolt connection is that in the actual application scenario, an ideal plane cannot appear at the top of the mine tunnel. On the premise of reasonably fitting the area of the tray 2, it is difficult for the connecting arm 23, which is the extension of the plane of the tray 2, to fit the cave wall without adjustment. And the connection between the trays 2 requires timely adjustment of the angular relationship between the connecting arms 23 to facilitate the formation of a whole between the trays 2.

[0048] It should be noted that the connecting arm 23 has a certain thickness, and the bolt connection is on the side of the tray 2 close to the damping nut 13.

[0049] The implementation principle of a high-strength and high-impact work stress display and yield anchor rod body 1 in the embodiment of the present application is as follows: In actual application, technicians pre-measure, calculate and mark the fixed points on the mine tunnel wall, drill deep holes through the rock fracture layers around the cave wall at the fixed points on the cave wall, then inject a glass bottle filled with gel into the deep holes, and drive the anchor rod body 1 in this embodiment into the deep holes and crush the glass bottles filled inside, releasing the gel contained in the glass bottles. The gel solidifies when it meets the air, and with the friction of the cave wall in the deep holes, the end of the anchor rod body 1 without threads is bonded in the hole.

[0050] After the anchor rod body 1 is fixed, the tray 2, as the main structure for supporting the rock mass, transfers the huge load generated by the rock blocks with a tendency to crack near the anchor rod body 1 to the corresponding structure at the end of the anchor rod body 1.

[0051] Technicians need to pre-tighten the damping nut 13 in advance so that the side wall of the damping nut 13 abuts against one end of the energy-releasing yielding pipe 12 and continue to tighten the damping nut 13 with a pneumatic wrench, so that the damping nut 13 squeezes one end of the energy-releasing yielding pipe 12 until the middle part of the energy-releasing yielding pipe 12 is significantly bent and restricted by the shrinkage throat hoop 14, and the connection between the damping nut 13 and the energy-releasing yielding pipe 12 is completed.

[0052] After the tray 2 reaches the bearing limit, the energy-releasing yielding pipe 12 has a certain yielding distance to reduce the axial tearing force borne by the bolt body 1. When the rock mass supported by the tray 2 has a tearing tendency, the tray 2 is pressed down, and a huge load is transmitted to the tray 2. The tray 2 squeezes the energy-releasing yielding pipe 12. Since the damping nut 13 has squeezed the energy-releasing yielding pipe 12 into a middle bending part 22 during installation, the huge pressure transmitted by the tray 2 makes the energy-releasing yielding pipe 12 increase its bending state. The bending deformation of the energy-releasing yielding pipe 12 is the yielding distance. Within the safe range, the yielding deformation of the energy-releasing yielding pipe 12 can relieve the huge load approaching the limit value of the adjacent bolt body 1. In summary, the energy-releasing yielding pipe 12 is equivalent to a safety device. Before the load from the rock mass damages the bolt body 1, that is, before a safety accident occurs, the energy-releasing yielding pipe 12 must be damaged in advance. When the energy-releasing yielding pipe 12 deforms under a huge load, technicians can observe whether the shrinkage throat hoop 14 sleeved on it is damaged, or whether the distance between the guide plates 141 is within the safe range to judge whether it is necessary to process the rock mass fracture layer at this time.

[0053] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A high-strength, high-impact stress-displaying yielding anchor rod, comprising an anchor rod body (1), wherein one end of the anchor rod body (1) is provided with a threaded portion (11), characterized in that: Also includes; A tray (2) is perpendicular to the axial direction of the anchor rod body (1) and is arranged in the middle part of the anchor rod body (1), and the middle part is provided with a through hole (21) for inserting the anchor rod body (1); A pressure-releasing tube (12) is sleeved on one end of the threaded portion (11) on the anchor rod body (1), and one end of the inner wall is provided with a thread in the same direction that matches the threaded portion (11) on the anchor rod body (1), and the inner diameter of the end without the thread is larger than the inner diameter of the other end. When the pressure-releasing tube (12) is threadedly connected to the anchor rod body (1), the other end is a free end; A damping nut (13) is threadedly connected to the end of the threaded portion (11) of the anchor rod body (1), abuts against the end of the pressure-releasing tube (12), and squeezes the pressure-releasing tube (12) to a bent state; The drag reduction washer system (3) is arranged on the threaded portion (11) of the anchor rod body (1) between the pressure release tube (12) and the tray (2).

2. The high-strength, high-impact-energy stress-displaying yielding anchor rod according to claim 1, characterized in that: Also includes; A shrinkable throat hoop (14) is sleeved on the middle part of the pressure-releasing and allowing pipe (12), and its inner ring diameter is equal to the outer diameter of the curved part of the pressure-releasing and allowing pipe (12); An annular groove is provided in the middle portion of the outer wall of the pressure-releasing tube (12) and is used for positioning the shrink throat hoop (14).

3. The high-strength, high-impact-energy stress-displaying yielding anchor rod according to claim 1, characterized in that: The drag reducing washer system (3) comprises: A ball pad (31) is adapted to the anchor rod body (1) and is arranged at a portion of the anchor rod body (1) close to the tray (2); the side of the ball pad (31) close to the tray (2) is hemispherical, and accordingly, a hemispherical groove connected to the through hole (21) and adapted to the ball pad (31) is provided in the middle portion of the tray (2).

4. The high-strength, high-impact-energy stress-indicating yielding anchor rod according to claim 3, characterized in that: The drag reducing washer system (3) further comprises: An iron gasket (33) is arranged between the ball gasket (31) and the pressure-releasing tube (12) and is used for transmitting stress; A drag-reducing washer (32) is inserted between the anchor rod body (1) and the corresponding washer and the iron washer (33) to buffer the extrusion tendency of the tray (2).

5. The high-strength, high-impact-energy stress-displaying yielding anchor rod according to claim 1, characterized in that: The middle part of one side of the tray (2) close to the ball pad (31) is bent and protrudes from the plate surface.

6. The high-strength, high-impact-energy stress-indicating yielding anchor rod according to claim 1, characterized in that: Also includes; A connecting arm (23) is provided at each corner of the tray (2) and extends in a direction away from the tray (2); A connecting ring (24) is fixedly connected to an end of each connecting arm (23) away from the tray (2), and its ring surface is arranged perpendicular to the disk surface of the tray (2). The connecting rings (24) on different trays (2) can be connected as a whole by steel bolts.

7. The high-strength, high-impact-energy stress-indicating yielding anchor rod according to claim 6, characterized in that: One end of the connecting arm (23) is bolted to the tray (2) to adjust the orientation of the connecting arm (23).

8. The high-strength, high-impact-energy stress-indicating yielding anchor rod according to claim 1, characterized in that: The ball pad (31) and the damping nut (13) are both made of 45# steel; The material of the drag-reducing gasket (32) is composed of natural rubber.

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