An Inverted Wedge Expansion Pre-tightening Type Rock Mass Quick Anchoring Device and Method

Abstract

The present invention provides an inverted wedge expansion pre-tightening type rapid rock mass anchoring device and method, belonging to the technical field of engineering rock mass anchoring and protection. The invention utilizes an impact unit installed at the tail of the anchor head to impact the anchor head sliding block, causing the anchor head wedge plate to slide and rotate radially in the anchor head chute to form an inverted wedge structure. Then, the pulling force of the anchor cable on the anchor head sliding block is used to make the anchor head extrude the hole wall of the bedrock borehole to form an anchoring force. Finally, a force transfer rod passes through the anchor head and connects multiple anchoring units in series to form a large-tonnage anchoring system, which has the characteristics of fast installation speed, large tonnage, stability and durability. Secondly, rapid installation is achieved through the expansion and pre-tightening of the anchoring unit in the bedrock borehole, without the need for secondary tensioning, reducing the construction process. Finally, an inverted wedge structure is formed by utilizing the stiffness difference between the metal and the rock mass, giving full play to the shear strength advantage of the rock mass itself under high normal force, and is applicable to the emergency rescue in the early stage of slope rock mass collapse and the anchoring control in the early stage of large deformation of surrounding rock in underground caverns.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering rock mass anchoring and protection, and in particular to an inverted wedge expansion pre-tightening type rapid rock mass anchoring device and method. Background Technique

[0002] As a geological disaster that occurs frequently in recent years, the collapse of dangerous rock masses has characteristics such as randomness, diversity, and suddenness. The initial sliding before instability failure has a short duration. Once it occurs, the construction operation time left for emergency rescue personnel is short, which has become a major pain point in the field of emergency rescue technology. On the other hand, with the gradual advancement of deep engineering, after excavating a chamber in soft rock, it causes large deformation of the surrounding rock towards the free face and generates a relaxation zone within a certain depth from the excavation face. The problem of surrounding rock instability induced by untimely support has gradually become prominent. In the aspects of emergency rescue for the collapse of dangerous rock masses and control of large deformation of surrounding rock caused by underground chamber excavation, a scientific and effective rapid anchoring technology is one of the key scientific problems that urgently need to be broken through. Existing technologies mostly use conventional grouting anchor rods and cable bolts for reinforcement. However, after the installation of the anchoring structure of the grouting anchor rod, it is necessary to wait for the strength of the grout to meet the requirements before prestressing can be carried out, which often requires several days of setting time, resulting in its timeliness being unable to meet the actual needs of emergency rescue work and being difficult to achieve the effect of emergency rescue. Therefore, an anchoring technology that can simultaneously meet the requirements of convenient installation, large tonnage, and no risk of slippage has become an urgent need. Summary of the Invention

[0003] To solve the above problems in the prior art, the present invention provides an inverted wedge expansion pre-tightening type rapid rock mass anchoring device and method. The invention includes: an anchor head, an impact unit, a force transmission rod, an internal anchoring unit, a cable bolt, an external anchoring unit, an anchoring force, and a bearing plate. The impact unit is installed at the tail of the anchor head. By using the impact unit to impact the sliding block of the anchor head, the wedge plate of the anchor head slides and rotates radially in the anchor head chute to form an inverted wedge structure. Then, using the tension of the cable bolt on the sliding block of the anchor head, the anchor head is used to extrude the bedrock borehole to form an anchoring force. Finally, the force transmission rod passes through the anchor head and connects multiple anchoring units in series to form a large-tonnage anchoring system. To achieve the above purpose, the technical solution is as follows:

[0004] On the one hand, the present invention provides an inverted wedge expansion pre-tightening type rapid rock mass anchoring device, and the device includes:

[0005] An anchor head, which is used to contact the hole wall of the bedrock borehole and provide an anchoring force;

[0006] An impact unit, which is used to provide an impact force, transmit kinetic energy through impact, and realize the expansion of the anchor head. It is installed at the tail of the anchor head;

[0007] A force transmission rod, which is used to connect the impact unit with the anchor head, and the next force transmission rod;

[0008] Inner anchoring unit, used to connect the cable anchor and the force transfer rod at the outermost side of the bedrock borehole;

[0009] The cable anchor, used to connect the inner anchoring unit and the outer anchoring unit, and transmit the anchoring force into the bedrock;

[0010] Outer anchoring unit, used to connect the cable anchor, arranged outside the dangerous rock mass, and provide the anchoring force for the dangerous rock mass;

[0011] Bearing plate, used to disperse the pressure of the outer anchoring unit on the dangerous rock mass;

[0012] The anchor head, the impact unit and the force transfer rod form an anchoring unit.

[0013] Optionally, the anchor head includes:

[0014] Positioning head, used to gather and position the wedge plate;

[0015] The wedge plate, used to slide and rotate radially along the positioning head under the support of the sliding block, and contact the bedrock, and utilize the interaction force between the wedge structure and the hole wall of the bedrock borehole to provide the anchoring force for the cable anchor;

[0016] The sliding block, used to insert into the inside of the wedge plate to make the anchor head form an inverted wedge structure;

[0017] The process of the anchor head forming an inverted wedge structure is divided into two stages:

[0018] Anchor head pre-tightening stage, using the impact force of the impact unit on the sliding block to support the wedge plate on the hole wall of the bedrock borehole,

[0019] Anchoring force tensioning stage, using the tension of the force transfer rod on the sliding block to lock the wedge plate on the hole wall of the bedrock borehole.

[0020] Optionally, the impact unit includes:

[0021] Reaction frame, used to provide the support reaction force required by the impact unit, so that the impact force can be effectively transmitted to the wedge plate of the anchor head;

[0022] Spring, used to provide the impact force for the sliding block of the anchor head;

[0023] Tension rod, used to compress the spring and lock the impact unit;

[0024] Pre-locking mechanism, used to temporarily lock the spring and trigger the impact unit.

[0025] Optionally, the pre-locking mechanism includes: locking plate, release rod, rotating bracket, limit bracket and pull rope;

[0026] The first end of the locking plate is connected to the pulling rope. The locking plate is rotatably connected to the rotating bracket through a circular hole. The limiting bracket is used to limit the rotation direction of the locking plate.

[0027] A groove structure is provided at the first end of the release rod. The groove structure is in close contact with the second end of the locking plate. The second end of the release rod is connected to the sliding block of the anchor head.

[0028] Optionally, the reaction frame includes: a long strip metal plate and a disc;

[0029] The first end of the long strip metal plate is connected to the screw hole at the second end of the wedge plate of the anchor head. The second end of the long strip metal plate is connected to the screw hole on the side surface of the disc. The disc has a middle hole, and there are holes on both sides of the middle hole, which respectively pass through the retracting rod of the impact unit and the release rod of the impact unit.

[0030] Optionally, the force transmission rod includes: a rod body, a female head sleeve, a male head screw, a thrust mechanism, a limiting mechanism, and a tensile force measuring instrument;

[0031] The rod body fixedly installs the thrust mechanism and the limiting mechanism. The female head sleeve and the male head screw are threadedly installed at both ends of the rod body. A tensile force measuring instrument is installed inside the female head sleeve. The thrust mechanism is located inside the pre-locking mechanism of the impact unit and is used to push the sliding block of the anchor head towards the wedge plate of the anchor head during the tensioning stage of the anchoring force. The limiting mechanism is located outside the pre-locking mechanism of the impact unit and is used to fix the position of the anchor head on the force transmission rod;

[0032] The anchor head and the impact unit slide on the force transmission rod;

[0033] The force transmission rods are connected end to end to achieve the series connection of multiple anchoring units.

[0034] Optionally, the bearing plate includes: a circular metal plate, a circular tube, stiffening ribs, and reinforcing plates;

[0035] The circular metal plate has a middle hole. The circular tube is fixedly connected to the position of the middle hole of the circular metal plate. The stiffening ribs are fixedly connected to the outside of the circular tube, and the reinforcing plates are fixedly installed between the stiffening ribs.

[0036] Optionally, the calculation method of the inverted wedge angle of the anchor head includes:

[0037] According to the wedge plate, through formula (1), the inner wedge angle of the wedge plate is obtained.

[0038] (1)

[0039] In the formula: is the inner wedge angle of the wedge plate. is the inner height of the front part of the cross-section after the wedge plate is assembled. is the inner height at the tail of the cross-section after the wedge plate assembly, is the length of the wedge plate;

[0040] According to this slider, the outer wedge angle of the slider is obtained through formula (2),

[0041] (2)

[0042] In the formula: is the outer wedge angle of the slider, is the outer height at the front of the slider, is the outer height at the tail of the slider, is the length of the slider;

[0043] According to the inner wedge angle of this wedge plate and the outer wedge angle of this slider, the reverse wedge angle of the anchor head is obtained through formula (3),

[0044] (3)

[0045] In the formula: is the reverse wedge angle of the anchor head.

[0046] Optionally, the calculation method of the maximum value of this anchoring force includes:

[0047] According to the reverse wedge angle of this anchor head, the relationship between the normal force on the wedge plate and the cable anchor tension is obtained through formula (4),

[0048] (4)

[0049] In the formula: is the normal force on the wedge plate, is the cable anchor tension, is the friction coefficient between the wedge plate and the bedrock;

[0050] According to the relationship between the normal force on the wedge plate and the cable anchor tension, the relationship between the rock mass shear resistance and the normal force on the wedge plate is obtained through formula (5) and formula (6),

[0051] (5)

[0052] (6)

[0053] In the formula: is the rock mass shear resistance, is the cohesion of the bedrock, is the radius of the outer side tail after the anchor head expands into a reverse wedge, is the friction angle of the bedrock, is the length of the wedge plate;

[0054] According to the relationship between the shear resistance of the rock mass and the normal force on the wedge plate, the maximum value of the anchoring force is obtained through formula (7).

[0055] (7)

[0056] In the formula: is the maximum value of the anchoring force, that is, the maximum value of the cable anchor tension.

[0057] On the other hand, the present invention provides a rapid rock mass anchoring method with reverse wedge expansion pre-tightening, which is realized by a rapid rock mass anchoring device with reverse wedge expansion pre-tightening. The method includes:

[0058] S1. Calculate the maximum value of the anchoring force of each anchor head according to the rock mass parameters and the calculation method of the maximum value of the anchoring force;

[0059] S2. Obtain the prestress design value of each anchor head according to the maximum value of the anchoring force of each anchor head;

[0060] S3. Obtain the number of anchor heads according to the prestress design value of each anchor head;

[0061] S4. Assemble the force transfer rod, anchor head, impact unit, internal anchoring unit and cable anchor in sequence according to the anchoring unit assembly scheme and the number of anchor heads, and connect the force transfer rod in sequence to obtain the internal anchoring device;

[0062] S5. According to the internal anchoring device, compress the spring of the impact unit to the designed position and lock it, and release the tension rod of the impact unit to obtain the locked anchoring device;

[0063] S6. Place the locked anchoring device into the bedrock borehole, trigger the impact unit from inside to outside in sequence, so that the anchor head forms a reverse wedge structure to obtain the anchoring device in the bedrock borehole;

[0064] S7. According to the anchoring device in the bedrock borehole, pass the cable anchor of the internal anchoring device through the bearing plate to install the external anchoring unit to obtain the anchoring device of the rock mass;

[0065] S8. Apply tension to the cable anchor by a tensioning device to the prestress design value and lock it to complete the rapid anchoring of the rock mass.

[0066] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects:

[0067] The above solution includes, on the one hand, an anchor head, an impact unit, a force transfer rod, an internal anchoring unit, a cable anchor, an external anchoring unit, anchoring force and a bearing plate. The impact unit is installed at the tail of the anchor head. The impact unit impacts the sliding block of the anchor head to make the wedge plate of the anchor head slide and rotate radially in the anchor head chute to form an inverted wedge structure. Then, the tension of the cable anchor on the sliding block of the anchor head is used to make the anchor head extrude the bedrock borehole to form an anchoring force. Finally, the force transfer rod passes through the anchor head and connects multiple anchoring units in series to form a large-tonnage anchoring system, which has the characteristics of fast installation speed, large tonnage, stability and durability. On the second hand, rapid installation is achieved by expanding and pre-tightening the anchoring unit in the bedrock borehole, eliminating the need for secondary tensioning and reducing the construction process. On the third hand, an inverted wedge structure is formed by taking advantage of the stiffness difference between the metal and the rock mass, giving full play to the strength advantage of the rock mass itself, and is applicable to the rapid emergency rescue in the early stage of slope rock mass collapse and the anchoring control of large deformations of surrounding rocks in underground caverns. Description of the Drawings

[0068] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0069] Figure 1 is the installation schematic diagram of the device in the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention;

[0070] Figure 2 is the sectional view of the anchoring unit where the sliding block has not entered the wedge plate in the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention;

[0071] Figure 3 is the sectional view of the anchoring unit where the sliding block has entered the wedge plate in the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention;

[0072] Figure 4 is the structural schematic diagram of the wedge plate in the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention;

[0073] Figure 5 is the schematic diagram for calculating the inner wedge angle of the wedge plate in the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention;

[0074] Figure 6 is the schematic diagram for calculating the outer wedge angle of the sliding block in the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention;

[0075] Figure 7It is a schematic structural diagram of the impact unit of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0076] Figure 8 It is a schematic structural diagram of the force transmission rod of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0077] Figure 9 It is the front view of the bearing plate of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0078] Figure 10 It is the right view of the bearing plate of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0079] Figure 11 It is a schematic structural diagram of the pre-locking mechanism of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0080] Figure 12 It is a schematic diagram of the unlocking process of the pre-locking device of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0081] Figure 13 It is a flowchart of the calculation method of the inverted wedge angle of the anchor head of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0082] Figure 14 It is a flowchart of the calculation method of the maximum value of the anchoring force of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention;

[0083] Figure 15 It is a flowchart of an embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring method of the present invention.

[0084] Explanation of reference numerals in the figure: anchor head 1, impact unit 2, force transmission rod 3, inner anchoring unit 4, anchor cable 5, outer anchoring unit 6, bearing plate 7, bedrock 8, dangerous rock mass 9, anchoring unit 10, positioning head 101, wedge plate 102, sliding block 103, long strip metal plate 201, spring 202, retracting pull rod 203, release rod 204, disc 205, pre-locking mechanism 206, locking plate 207, limit bracket 208, rotating bracket 209, pull rope 210, rod body 301, female head sleeve 302, male head screw 303, thrust mechanism 304, limit mechanism 305, tensile force measuring instrument 306, circular metal plate 701, circular tube 702, stiffening rib 703, reinforcing plate 704. Detailed implementation manners

[0085] The technical solutions in the present invention will be described below with reference to the accompanying drawings.

[0086] 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.

[0087] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0088] like Figure 1 The schematic diagram of the installation of the inverted wedge-shaped expansion pre-tightening type rock mass fast anchoring device embodiment of the present invention is shown. The present invention provides an inverted wedge-shaped expansion pre-tightening type rock mass fast anchoring device, which can implement an inverted wedge-shaped expansion pre-tightening type rock mass fast anchoring method. The device includes: an anchor head 1, an impact unit 2, a force transmission rod 3, an inner anchoring unit 4, an anchor cable 5, an outer anchoring unit 6, and a pressure plate 7;

[0089] An anchor head 1, used to contact the wall of the hole drilled in the bedrock 8 to provide anchoring force;

[0090] Specifically, Figure 2 The cross-sectional view of the anchoring unit of the inverted wedge-shaped expansion pre-tightening rock mass quick anchoring device embodiment of the present invention, in which the sliding block does not enter the wedge-shaped plate, and Figure 3 The cross-sectional view of the sliding block of the embodiment of the inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device of the present invention entering the anchoring unit of the wedge-shaped plate is shown, and the anchor head 1 comprises:

[0091] A positioning head 101 is used to gather and position the wedge plate 102;

[0092] Furthermore, the structure of the positioning head 101 is a cylindrical structure, with a hole in the middle for the force transmission rod 3 to pass through, square holes on all sides, and openings on the outside of the square holes, which serve as slide grooves for the wedge plate 102. The sliding displacement and rotation angle of the wedge plate 102 can occur synchronously during the outward expansion process, and the anchor head 1 can adapt to the hardness of the rock mass to squeeze the rock mass to form an inverted wedge structure.

[0093] The wedge plate 102 is used to slide and rotate along the radial direction of the positioning head 101 under the support of the sliding block, and contact the bedrock 8, and use the interaction force between the wedge structure and the wall of the hole drilled in the bedrock 8 to provide the anchoring force for the anchor cable 5;

[0094] Furthermore, if Figure 4Schematic diagram of the structure of the wedge plate in the embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention shown. The cross-section of the wedge plate 102 is a quarter of a circular ring, the outer side is an arc, the inner side is a plane, there is an inverted wedge anti-slip step on the outer side along the longitudinal section, and there is a protruding cylinder at the front end as a force transmission column, which is used to insert into the chute of the positioning head 101, and then can slide radially along the chute and rotate around the chute during the expansion of the wedge plate 102 in all directions, so that the anchor head 1 forms an inverted wedge structure.

[0095] The sliding block 103 is used to insert into the inside of the wedge plate 102 to make the anchor head 1 form an inverted wedge structure;

[0096] Further, the wedge plate 102 is installed in the chute of the positioning head 101 to form a cylindrical hollow structure, and the sliding block 103 is installed in the cylindrical hollow structure of the wedge plate 102;

[0097] Specifically, as Figure 5 Schematic diagram of calculating the inner wedge angle of the wedge plate in the embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention shown, as Figure 6 Schematic diagram of calculating the outer wedge angle of the sliding block in the embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention shown and as Figure 13 Flowchart of the calculation method of the inverted wedge angle of the anchor head in the embodiment of the inverted wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention shown. The calculation method of the inverted wedge angle of the anchor head includes:

[0098] According to the wedge plate 102, through formula (1), the inner wedge angle of the wedge plate is obtained,

[0099] (1)

[0100] In the formula: is the inner wedge angle of the wedge plate, is the inner height at the front part of the cross-section of the wedge plate after assembly, is the inner height at the tail part of the cross-section of the wedge plate after assembly, is the length of the wedge plate;

[0101] According to the sliding block 103, through formula (2), the outer wedge angle of the sliding block is obtained,

[0102] (2)

[0103] In the formula: is the outer wedge angle of the sliding block, is the outer height at the front part of the sliding block, is the outer height at the tail part of the sliding block, is the length of the sliding block;

[0104] According to the inner wedge angle of the wedge plate and the outer wedge angle of the sliding block, the reverse wedge angle of the anchor head is obtained through formula (3).

[0105] (3)

[0106] Where: is the reverse wedge angle of the anchor head.

[0107] The process of forming the reverse wedge structure of the anchor head 1 is divided into two stages:

[0108] During the anchor head pre-tightening stage, the impact force of the impact unit 2 on the sliding block 103 is used to support the wedge plate 102 on the hole wall of the drill hole in the bedrock 8.

[0109] During the anchoring force tensioning stage, the tension of the force transfer rod 3 on the sliding block 103 is used to lock the wedge plate 102 on the hole wall of the drill hole in the bedrock 8.

[0110] Specifically, as Figure 14 shown in the flowchart of the calculation method of the maximum value of the anchoring force in the embodiment of the reverse wedge expansion pre-tightening type rapid rock mass anchoring device of the present invention, the calculation method of the maximum value of the anchoring force includes:

[0111] According to the reverse wedge angle of the anchor head, the relationship between the normal force on the wedge plate and the anchor cable tension is obtained through formula (4).

[0112] (4)

[0113] Where: is the normal force on the wedge plate, is the anchor cable tension, is the friction coefficient between the wedge plate and the bedrock;

[0114] According to the relationship between the normal force on the wedge plate and the anchor cable tension, the relationship between the rock mass shear resistance and the normal force on the wedge plate is obtained through formula (5) and formula (6).

[0115] (5)

[0116] (6)

[0117] Where: is the rock mass shear resistance, is the cohesion of the bedrock, is the radius of the tail of the outer side surface after the anchor head expands into a reverse wedge, is the friction angle of the bedrock, is the length of the wedge plate;

[0118] According to the relationship between the shear force of the rock mass and the normal force received by the wedge plate, the maximum value of the anchoring force is obtained through formula (7).

[0119] (7)

[0120] In the formula: is the maximum value of the anchoring force, that is, the maximum value of the cable anchor tension.

[0121] According to the shear strength of the rock mass, the friction angle, and the reverse wedge angle of the anchor head, the maximum value of the anchoring force that each anchor head can provide can be calculated using formula (7).

[0122] The cable anchor tension can be designed based on the maximum value of the anchoring force of the anchor head. The cable anchor tension is less than the maximum value of the anchoring force of the anchor head, and the number of series-connected anchoring units 10 is determined according to the designed cable anchor tension.

[0123] The impact unit 2 is used to provide an impact force, transfer kinetic energy through impact, and cause the anchor head 1 to expand. It is installed at the tail of the anchor head 1.

[0124] Specifically, as Figure 7 shown in the structural schematic diagram of the impact unit of the reverse wedge expansion pre-tightening type rapid rock mass anchoring device embodiment of the present invention, the impact unit 2 includes:

[0125] The reaction frame is used to provide the support reaction force required by the impact unit 2, so that the impact force can be effectively transmitted to the wedge plate 102 of the anchor head 1.

[0126] The spring 202 is used to provide the impact force for the sliding block 103 of the anchor head 1.

[0127] The pull rod 203 is used to compress the spring 202 and lock the impact unit 2.

[0128] The pre-locking mechanism 206 is used to temporarily lock the spring 202 and trigger the impact unit 2.

[0129] Furthermore, as Figure 11 shown in the structural schematic diagram of the pre-locking mechanism of the reverse wedge expansion pre-tightening type rapid rock mass anchoring device embodiment of the present invention, the pre-locking mechanism 206 includes: a locking plate 207, a release rod 204, a rotating bracket 209, a limiting bracket 208, and a pull rope 210;

[0130] The first end of the locking plate 207 is connected to the pull rope 210. The locking plate 207 is rotatably connected to the rotating bracket 209 through a round hole. The limiting bracket 208 is used to limit the rotation direction of the locking plate 207.

[0131] The first end of the release rod 204 is provided with a groove structure which is in fitting contact with the second end of the locking plate 207, and the second end of the release rod 204 is connected to the sliding block 103 of the anchor head 1;

[0132] The pre-locking mechanism 206 is used to replace the retracting rod 203. After the spring 202 is locked, the nut on the retracting rod 203 is removed, so that the retracting rod 203 loses its function, and then the impact timing of the spring 202 is controlled by the pre-locking mechanism 206;

[0133] As Figure 12 Shown is a schematic diagram of the unlocking process of the pre-locking device of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device embodiment of the present invention. One end of the pull rope 210 is connected to the first end of the locking plate 207, and the other end extends outside the rock mass drill hole. By pulling the pull rope 210 outside the rock mass drill hole, the locking plate 207 rotates around the center of the arc, and then the release rod 204 is disengaged from the locking plate 207.

[0134] The reaction frame includes: a long strip metal plate 201 and a disc 205;

[0135] The first end of the long strip metal plate 201 is connected to the screw hole at the second end of the wedge plate 102 of the anchor head 1, the second end of the long strip metal plate 201 is connected to the screw hole on the side surface of the disc 205, the disc 205 has a middle hole, and there are holes on both sides of the middle hole, through which the retracting rod 203 of the impact unit 2 and the release rod 204 of the impact unit 2 pass respectively.

[0136] The force transmission rod 3 is used to connect the impact unit 2 with the anchor head 1 and the next force transmission rod;

[0137] Specifically, as Figure 8 Shown is a schematic diagram of the structure of the force transmission rod of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device embodiment of the present invention. The force transmission rod 3 includes: a rod body 301, a female head sleeve 302, a male head screw 303, a thrust mechanism 304, a limiting mechanism 305 and a tensile force measuring instrument 306;

[0138] The rod body 301 fixedly installs the thrust mechanism 04 and the limiting mechanism 305. The female head sleeve 302 and the male head screw 303 are threadedly installed at both ends of the rod body 301. A tensile force measuring instrument 306 is installed inside the female head sleeve 302. The thrust mechanism 304 is located inside the pre-locking mechanism 206 of the impact unit 2 and is used to push the sliding block of the anchor head towards the wedge plate 102 of the anchor head 1 during the anchoring force tensioning stage. The limiting mechanism 305 is located outside the pre-locking mechanism 206 of the impact unit 2 and is used to fix the position of the anchor head 1 on the force transmission rod 3;

[0139] The anchor head 1 and the impact unit 2 slide on the force transmission rod 3;

[0140] The load transfer bar 3 is connected end to end to realize the series connection of multiple such anchoring units 10;

[0141] Further, the tensile force measuring instrument 306 in the innermost female head sleeve 302 among multiple load transfer bars 3 only monitors the anchoring force provided by the innermost anchor head, which is gradually accumulated from the bottom of the bedrock 8 borehole to the orifice of the bedrock 8 borehole. That is, the tensile force measuring instrument 306 in the outermost female head sleeve monitors the total anchoring force of multiple anchor heads, and the anchoring force provided by each anchor head can be obtained by subtraction.

[0142] The inner anchoring unit 4 is used to connect the anchor cable 1 and the outermost load transfer bar 3 of the bedrock 8 borehole;

[0143] The anchor cable 5 is used to connect the inner anchoring unit 4 and the outer anchoring unit 6, and transmit the said anchoring force into the bedrock 8;

[0144] The outer anchoring unit 6 is used to connect the anchor cable 5, is arranged outside the dangerous rock mass 9, and provides the said anchoring force for the dangerous rock mass 9;

[0145] The bearing plate 7 is used to disperse the pressure of the outer anchoring unit 6 on the dangerous rock mass 9;

[0146] Specifically, as Figure 9 the front view of the bearing plate of the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention shown in Figure 10 and the right view of the bearing plate of the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring device of the present invention shown in

[0147] The bearing plate 7 includes: a circular metal plate 701, a circular tube 702, stiffening ribs 703 and reinforcing plates 704;

[0148] The circular metal plate 701 has a middle hole, the circular tube 702 is fixedly connected to the position of the middle hole of the circular metal plate 701, the stiffening ribs 703 are fixedly connected to the outside of the circular tube 702, and the reinforcing plates 704 are fixedly installed between the stiffening ribs 703.

[0149] The anchor head 1, the impact unit 2 and the load transfer bar 3 form an anchoring unit 10.

[0150] As Figure 15 the flowchart of the embodiment of the inverted wedge expansion pre-tightening type rock mass rapid anchoring method of the present invention shown in

[0151] S1. According to the rock mass parameters and the calculation method of the maximum value of the anchoring force, obtain the maximum value of the anchoring force of each anchor head;

[0152] S2. Obtain the prestress design value of each anchor head according to the maximum value of the anchoring force of each anchor head;

[0153] S3. Obtain the number of anchor heads according to the prestress design value of each anchor head;

[0154] S4. According to the assembly scheme of the anchoring unit and the number of anchor heads, sequentially assemble the load transfer rod, anchor head, impact unit, internal anchoring unit and anchor cable, and connect the load transfer rods in sequence to obtain the internal anchoring device;

[0155] S5. According to the internal anchoring device, compress the spring of the impact unit to the designed position and lock it, and release the tension rod of the impact unit to obtain the locked anchoring device;

[0156] S6. Place the locked anchoring device into the bedrock borehole, and sequentially trigger the impact unit from the inside to the outside to make the anchor head form an inverted wedge structure, so as to obtain the anchoring device in the bedrock borehole;

[0157] S7. According to the anchoring device in the bedrock borehole, pass the anchor cable of the internal anchoring device through the bearing plate to install the external anchoring unit to obtain the anchoring device of the rock mass;

[0158] S8. Apply tension to the anchor cable by a tensioning device to the prestress design value and lock it to complete the rapid anchoring of the rock mass.

[0159] The present invention provides an inverted wedge expansion pre-tightening type rapid rock mass anchoring device and control method. The invention includes an anchor head, an impact unit, a load transfer rod, an internal anchoring unit, an anchor cable, an external anchoring unit, an anchoring force and a bearing plate. The impact unit is installed at the tail of the anchor head. The impact unit impacts the sliding block of the anchor head to make the wedge plate of the anchor head slide and rotate radially in the anchor head chute to form an inverted wedge structure. Then, the tension of the anchor cable on the sliding block of the anchor head is used to make the anchor head extrude the bedrock borehole to form an anchoring force. Finally, the load transfer rod passes through the anchor head and connects multiple anchoring units in series to form a large-tonnage anchoring system, which has the characteristics of fast installation speed, large tonnage, stability and durability. Secondly, rapid installation is realized by the expansion and pre-tightening of the anchoring unit in the bedrock borehole, and secondary tensioning is not required, reducing the construction process. Finally, the inverted wedge structure is formed by using the stiffness difference between the metal and the rock mass, giving full play to the strength advantage of the rock mass itself, and is suitable for the rapid emergency rescue in the early stage of slope rock mass collapse and the anchoring control of large deformation of surrounding rock in underground caverns.

[0160] It is understood that the present invention is described by the above embodiments and should not be construed as limiting the embodiments and scope of the present invention. As is known to those skilled in the art, various changes or equivalent replacements can be made to these features and embodiments without departing from the spirit and scope of the present invention. Additionally, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the scope protected by the present invention.

Claims

1. An inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device, characterized in that: The device comprises: An anchor head, used to contact the wall of the bedrock borehole to provide anchoring force; An impact unit, used to provide impact force, transfer kinetic energy through impact, realize expansion of the anchor head, and installed at the tail of the anchor head; A dowel rod, used to connect the impact unit with the anchor head and the next dowel rod; An inner anchoring unit, used for connecting the anchor cable and the outermost force transmission rod of the bedrock borehole; The anchor cable is used to connect the inner anchor unit and the outer anchor unit to transmit the anchoring force to the inside of the bedrock; An external anchoring unit, used to connect the anchor cable, arranged outside the dangerous rock mass, and providing the anchoring force for the dangerous rock mass; A pressure plate, used to disperse the pressure of the external anchoring unit on the dangerous rock mass; The anchor head, the impact unit and the force transmission rod form an anchoring unit; The anchor head comprises: A positioning head, used to gather and position the wedge plate; The wedge plate is used to slide and rotate along the radial direction of the positioning head under the support of the sliding block, and to contact the bedrock, and to provide the anchoring force for the anchor cable by using the interaction force between the wedge structure and the wall of the bedrock borehole; The sliding block is used to be inserted into the interior of the wedge-shaped plate so that the anchor head forms an inverted wedge-shaped structure; The impact unit comprises: A reaction frame, used to provide the supporting reaction force required by the impact unit, so that the impact force can be effectively transmitted to the wedge plate of the anchor head; A spring, used for providing the impact force to the sliding block of the anchor head; A retracting rod, used for compressing the spring and locking the impact unit; The pre-locking mechanism is used to temporarily lock the spring and trigger the impact unit.

2. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 1 is characterized in that: The process of forming the inverted wedge-shaped structure of the anchor head is divided into two stages: In the anchor head pre-tightening stage, the impact force of the impact unit on the sliding block is used to support the wedge plate on the hole wall of the bedrock borehole. In the anchoring force tensioning stage, the wedge plate is locked to the hole wall of the bedrock borehole by utilizing the tension of the force transmission rod on the sliding block.

3. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 1 is characterized in that: The pre-locking mechanism comprises: a locking plate, a release rod, a rotating bracket, a limiting bracket and a pull rope; The first end of the locking plate is connected to the pull rope, the locking plate is rotatably connected to the rotating bracket through a circular hole, and the limiting bracket is used to limit the rotation direction of the locking plate. A groove structure is provided at the first end of the release rod, and the groove structure is in close contact with the second end of the locking plate. The second end of the release rod is connected to the sliding block of the anchor head.

4. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 3 is characterized in that: The reaction frame comprises: a long metal plate and a disc; The first end of the long metal plate is connected to the second end screw hole of the wedge plate of the anchor head, and the second end of the long metal plate is connected to the side screw hole of the disc. The disc has a middle hole, and holes are provided on both sides of the middle hole, through which the retracting rod and the release rod of the impact unit are respectively passed.

5. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 1 is characterized in that: The force transmission rod comprises: a rod body, a female sleeve, a male screw, a thrust mechanism, a limit mechanism and a tension measuring instrument; The thrust mechanism and the limit mechanism are fixedly installed on the rod body, the female sleeve and the male screw are threadedly installed on both ends of the rod body, a tension measuring instrument is installed in the female sleeve, the thrust mechanism is located on the inner side of the pre-locking mechanism of the impact unit, and is used to push the sliding block of the anchor head to move toward the wedge plate of the anchor head during the anchoring force tensioning stage, and the limit mechanism is located on the outer side of the pre-locking mechanism of the impact unit, and is used to fix the position of the anchor head on the force transmission rod; The anchor head and the impact unit slide on the force transmission rod; The force transmission rods are connected head to tail to realize the series connection of multiple anchoring units.

6. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 1 is characterized in that: The pressure bearing plate comprises: a round metal plate, a round tube, a stiffening rib and a reinforcement plate; The circular metal plate has a middle hole, the circular tube is fixedly connected to the middle hole of the circular metal plate, the outer side of the circular tube is fixedly connected to the stiffening ribs, and the reinforcing plates are fixedly installed between the stiffening ribs.

7. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 2 is characterized in that: The calculation method of the inverted wedge angle of the anchor head comprises: According to the wedge plate, the inner wedge angle of the wedge plate is obtained by formula (1): （1） Where: is the inner wedge angle of the wedge plate, The front inside height of the cross section after the wedge plate is assembled, The height of the rear inner side of the cross section after the wedge plate is assembled. is the length of the wedge plate; According to the sliding block, the outer wedge angle of the sliding block is obtained by formula (2): （2） Where: is the outer wedge angle of the slider, is the outer front height of the slider, is the outer height of the slider tail, is the length of the slider; According to the inner wedge angle of the wedge plate and the outer wedge angle of the sliding block, the reverse wedge angle of the anchor head is obtained by formula (3): （3） Where: It is the inverted wedge angle of the anchor head.

8. The inverted wedge-shaped expansion pre-tightening rock mass rapid anchoring device according to claim 7 is characterized in that: The method for calculating the maximum value of the anchoring force includes: According to the inverted wedge angle of the anchor head, the relationship between the normal force on the wedge plate and the anchor cable tension is obtained by formula (4): （4） Where: is the normal force on the wedge plate, is the anchor cable tension, is the friction coefficient between the wedge plate and the bedrock; According to the relationship between the normal force on the wedge plate and the tension of the anchor cable, the relationship between the shear force of the rock mass and the normal force on the wedge plate is obtained by formula (5) and formula (6): （5） （6） Where: is the shear resistance of rock mass, is the cohesion of the bedrock, The radius of the tail of the outer side after the anchor head expands into an inverted wedge shape. is the friction angle of bedrock, is the length of the wedge plate; According to the relationship between the rock mass shear resistance and the normal force on the wedge plate, the maximum anchoring force is obtained by formula (7): （7） Where: It is the maximum value of the anchoring force, that is, the maximum value of the anchor cable tension.

9. A method for rapid rock anchoring with an inverted wedge-shaped expansion pre-tightening method, which is implemented by the inverted wedge-shaped expansion pre-tightening rapid rock anchoring device according to any one of claims 1 to 8, characterized in that: The method comprises: S1. According to the rock mass parameters and the maximum anchoring force calculation method, the maximum anchoring force of each anchor head is obtained; S2. according to the maximum value of the anchoring force of each anchor head, obtain the prestress design value of each anchor head; S3. Obtaining the number of anchor heads according to the prestress design value of each anchor head; S4, according to the anchor unit assembly scheme and the number of anchor heads, assemble the dowel rod, the anchor head, the impact unit, the inner anchor unit and the anchor cable in sequence, and connect the dowel rods in sequence to obtain the internal anchor device; S5. According to the internal anchoring device, compress the spring of the impact unit to the designed position to lock and release the retracting rod of the impact unit to obtain a locked anchoring device; S6, placing the locked anchoring device into a bedrock borehole, triggering the impact units in sequence from the inside to the outside, so that the anchor head forms an inverted wedge structure, and obtaining an anchoring device in the bedrock borehole; S7, according to the anchoring device in the bedrock borehole, passing the anchor cable of the internal anchoring device through the pressure plate to install the external anchoring unit, so as to obtain the anchoring device of the rock mass; S8. Apply tension to the anchor cable to the prestressed design value through tensioning equipment and lock it to complete the rapid anchoring of the rock mass.

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