A local built-in surrounding rock self-locking tray device and its usage method

Abstract

The present invention relates to the technical field of surrounding rock support in mining engineering, and provides a locally built-in surrounding rock self-locking tray and a using method. The locally built-in surrounding rock self-locking tray includes a local reaming bit, an inner surrounding rock self-locking tray, a casing, and grinding teeth. The local reaming bit is a variable-diameter bit, the tray is a variable-diameter tray, and the reaming area formed by the tray and the local reaming bit can be seamlessly and tightly butt-jointed. The using method is as follows: when drilling to the last drill pipe, the local reaming bit and the casing are successively sleeved on the last drill pipe. After drilling to the designated position, stop drilling until the grinding teeth grind the uneven surrounding rock surface flat. Finally, install the tray and the anchor cable. In the method of the present invention, the tray does not need to install additional anchors. Through multi-stage variable diameter, the stress performance is good, the overall bearing capacity is strong, the tray support system is stable and reliable, and is not affected by repeated supports such as brackets and is not damaged. It has strong adaptability, and the drilling and reaming are integrally formed, with the characteristics of convenience and speed.

Description

Technical Field

[0001] The invention relates to the technical field of surrounding rock support for mining projects, and in particular to a partially built-in surrounding rock self-locking tray device and a use method thereof. Background Art

[0002] Anchor support technology is widely used in tunnel surrounding rock control, slope reinforcement, etc. It is a key means to achieve stability of surrounding rock and other projects. The anchor cable has high strength, high rigidity, wide anchoring range, convenient transportation, quick use and good anchoring effect.

[0003] The anchor and the tray in the traditional anchoring installation method are independent of each other. The anchor cable transmits the working resistance to the tray through the anchor cable, and the tray then transmits the force to the surrounding rock to play an anchoring role. It can be seen that the realization of the anchoring performance of the anchor cable is limited by the anchor cable, and it must be used effectively in combination to achieve the anchoring effect. The traditional installation method is prone to the following problems: (1) The anchor cable and the tray are prone to uncoordinated force during the transmission of the working resistance of the anchor cable, resulting in damage to the anchor or the tray. When the surrounding rock deforms uncoordinatedly, the anchor cable at the connection between the anchor and the tray is subjected to strong shear force, which can easily cause abnormal shear and breakage of the anchor cable; (2) For larger anchor cable trays, the smaller anchor causes extremely unbalanced force on the tray, or the anchor cannot transmit the working resistance of the anchor cable to the tray well. At this time, the general method is to increase the size of the tray to be about 1 times smaller than that of the large tray. The 1 to 3 small tray gaskets on the right will affect the installation efficiency. The stacked trays are independent and have weak shear resistance. The area where the anchor cable passes through the tray is subjected to abnormal shear force, which reduces the ultimate performance of the anchor cable. The more stacked trays are, the more obvious the protruding surrounding rock part is, which significantly reduces the usable cross-section of the tunnel space and affects the movement of equipment; (3) When the anchor cable is arranged at an angle, although there are universal anchors, the long-term uncoordinated force will still cause the anchor and tray to fail due to abnormal force; (4) The anchor is easily damaged in the long-term external corrosion environment and the external anchor is easily damaged under the action of mechanical external force. The damage of the anchor induces the failure of the support system, thereby causing serious safety accidents; (5) The uneven surface of the surrounding rock will aggravate the stress concentration of the tray and the anchor, and the force is extremely unbalanced and fails. The support effect is far from meeting the design requirements. Summary of the invention

[0004] To achieve the above object, the present invention provides the following technical solution: a partially built-in surrounding rock self-locking tray device, comprising a partially reaming drill bit, a partially built-in surrounding rock self-locking tray, a casing and ground teeth;

[0005] The local hole reaming drill bit is a multi-stage variable diameter drill bit, which comprises a first-stage toothless disc, a second-stage toothed frustum, and a third-stage toothed frustum. The first-stage toothless disc is provided with holes for grinding teeth. The local hole reaming drill bit is provided with a drill rod passage hole in the interior. The drill rod passage hole is a regular polygon and is consistent with the cross-sectional shape of the drill rod.

[0006] The locally built-in surrounding rock self-locking tray is a multi-stage variable-diameter tray, which are respectively the first-stage external part of the tray, the second-stage built-in frustum of the tray, and the third-stage built-in frustum of the tray;

[0007] The included angle between the central axis of the cable anchor hole of the locally built-in surrounding rock self-locking tray and the lower bottom surface of the locally built-in surrounding rock self-locking tray is 45°-90°;

[0008] The second-stage built-in frustum and the third-stage built-in frustum of the locally built-in surrounding rock self-locking tray are seamlessly and tightly butted with the reamed area formed by the locally reaming bit.

[0009] As a further scheme of the present invention, the thickness of the first-stage toothless disc of the locally reaming bit is 1 cm - 3 cm; when the surface of the surrounding rock is intact, the radius R1 of the first-stage toothless disc takes a value of 3 cm - 10 cm, and when the surface of the surrounding rock is incomplete, resulting in abnormal contact between the locally built-in surrounding rock self-locking tray and the surrounding rock and affecting the anchoring effect, the radius R1 of the first-stage toothless disc takes a value equal to half of the width r1 of the first-stage external part of the locally built-in surrounding rock self-locking tray.

[0010] As a further scheme of the present invention, the height H2 of the second-stage toothed frustum of the locally reaming bit is 1 cm - 5 cm, the included angle β2 between the side surface and the upper bottom surface of the second-stage toothed frustum is 45°-90°, the radius R of the lower bottom surface of the second-stage toothed frustum 22 is 3 cm - 10 cm, the radius R2 of the upper bottom surface of the second-stage toothed frustum is 3 cm - 10 cm, and R2 < R 22 .

[0011] As a further scheme of the present invention, the height H3 of the third-stage toothed frustum of the locally reaming bit is 1 cm - 5 cm, the included angle β3 between the side surface and the upper bottom surface of the third-stage toothed frustum is 45°-90°, the radius R of the lower bottom surface of the third-stage toothed frustum 33 is 3 cm - 9 cm, the radius R3 of the upper bottom surface of the third-stage toothed frustum is 1 cm - 7 cm, and R3 < R 33 .

[0012] As a further scheme of the present invention, the thickness h1 of the first-stage external part of the locally built-in surrounding rock self-locking tray is 1 cm - 4 cm, the shape of the first-stage external part of the tray is square or circular, and the half of the width r1 of the first-stage external part of the tray is 10 cm - 30 cm.

[0013] As a further solution of the present invention, the height h2 of the second-order built-in conical platform of the tray of the locally built-in surrounding rock self-locking tray is 1 cm to 5 cm, the included angle α2 between the side surface and the upper bottom surface of the second-order built-in conical platform of the tray is 45° to 90°, and the radius r of the lower bottom surface of the second-order built-in conical platform of the tray 22 is 3 cm to 10 cm, the radius r2 of the upper bottom surface of the second-order built-in conical platform is 3 cm to 10 cm, and r2 < r 22 .

[0014] As a further solution of the present invention, the height h3 of the third-order built-in conical platform of the tray of the locally built-in surrounding rock self-locking tray is 1 cm to 5 cm, the included angle α3 between the side surface and the upper bottom surface of the third-order built-in conical platform is 45° to 90°, and the radius r of the lower bottom surface of the third-order built-in conical platform 33 is 3 cm to 9 cm, the radius r3 of the upper bottom surface of the third-order built-in conical platform is 1 cm to 7 cm, and r3 < r 33 ; H2 = h2, H3 = h3, R3 = r3 < R 33 = r 33 ≤ R2 = r2 < R 22 = r 22 < r1, α3 = β3, α2 = β2.

[0015] A method for using a locally built-in surrounding rock self-locking tray device, the specific steps include:

[0016] Step 1. Select the model of the locally built-in surrounding rock self-locking tray:

[0017] The included angle between the anchor cable borehole and the bedding plane of the surrounding rock is The included angle between the central axis of the tray anchor cable passage hole and the lower bottom surface is α0, The minimum value is 0°, and the maximum value is 2°;

[0018] An anchor cable dumping groove is arranged on the first-order built-in disc of the tray, and it is appropriate that the volume space of the anchor cable dumping groove per unit length is basically equal to the volume of the anchor cable under the condition of per unit length;

[0019] Step 2. Determine the length of the casing, and the length of the casing is equal to the length of the last drill pipe minus the depth that the last drill pipe is designed to drill and minus the thickness of the first-order toothless disc;

[0020] Step 3. When the anchor cable borehole is drilled to the last drill pipe, while connecting the last drill pipe, successively put on the locally reaming bit and the casing on the last drill pipe;

[0021] Step 4. After drilling to the specified depth, that is, when the first-order toothless disc is close to the surface of the surrounding rock, continue to rotate until the uneven surface of the surrounding rock is ground flat by the grinding teeth and then stop drilling;

[0022] Step Five: Finally, install the selected locally built-in surrounding rock self-locking tray, anchor cable and wedge, and tension them to the designed pre-tightening force.

[0023] The beneficial effects of the present invention are as follows: (1) Fundamentally, it revolutionizes the traditional anchorage method that must be combined with a tray to achieve the anchorage purpose. It realizes that no separate anchorage is required. The tray is locally built into the surrounding rock, and the tray itself can achieve high-strength self-locking, so it is not restricted by the anchorage; (2) The local reaming bit realizes the function of integrating the anchor cable drilling and micro-reaming, with the characteristic of high efficiency; (3) The local reaming bit realizes the function of smoothing the surface of the surrounding rock, so that the tray fits more tightly with the surface of the surrounding rock, and the anchorage performance is significantly improved; (4) By the way of locally building in the tray with multiple-stage variable diameters, the anchorage performance of the tray is significantly improved and the function of integrating with the surrounding rock is realized; (5) When the anchor cable is arranged obliquely, the anchor cable hole channel of the tray is consistent with the inclination angle of the anchor cable arrangement, avoiding a large shear force between the tray and the anchor cable when the anchor cable is arranged obliquely; (6) In the moving area of the hydraulic support, the tray has a groove for the anchor cable to fall. There is no influence between the movement of the support and the anchorage of the tray and the exposed anchor cable, realizing high-stability anchorage, strong adaptability, and the function of integrating the anchor cable drilling and reaming, with the characteristics of convenience and quickness, and having very wide and important popularization and application value. Description of the Drawings

[0024] Figure 1 It is a schematic diagram of the local reaming bit;

[0025] Figure 2 It is a schematic diagram of the cross-section I-1 of the local reaming bit;

[0026] Figure 3 It is a front view schematic diagram of the locally built-in surrounding rock self-locking tray (α0 < 90°);

[0027] Figure 4 It is for Figure 3 the top view schematic diagram of the locally built-in surrounding rock self-locking tray (α0 < 90°);

[0028] Figure 5 It is for Figure 4 the I-I cross-section schematic diagram of the locally built-in surrounding rock self-locking tray (α0 < 90°);

[0029] Figure 6 It is a front view schematic diagram of the locally built-in surrounding rock self-locking tray (α0 = 90°);

[0030] Figure 7 It is for Figure 6 the I-I cross-section schematic diagram of the locally built-in surrounding rock self-locking tray (α0 = 90°);

[0031] Figure 8Schematic front view of the locally built-in surrounding rock self-locking tray (with a trough for cable anchor dumping);

[0032] Figure 9 It is Figure 8 Schematic top view of the locally built-in surrounding rock self-locking tray (with a trough for cable anchor dumping);

[0033] Figure 10 It is Figure 8 Schematic bottom view of the locally built-in surrounding rock self-locking tray (with a trough for cable anchor dumping);

[0034] Figure 11 It is Figure 10 Schematic sectional view II-II of the locally built-in surrounding rock self-locking tray (with a trough for cable anchor dumping);

[0035] Figure 12 It is the drill pipe casing and the sectional view;

[0036] Figure 13 Schematic diagram of the process of the integrated cable anchor drilling - micro - reaming method;

[0037] Figure 14 Schematic diagram of the integrated cable anchor drilling - micro - reaming when drilling to the specified depth;

[0038] Figure 15 Schematic diagram of the hole formation of the integrated cable anchor drilling - micro - reaming;

[0039] Figure 16 Schematic diagram of the installation of the tray and the cable anchor when α0 = 90°;

[0040] Figure 17 Schematic diagram of the installation of the tray and the cable anchor when α0 < 90°;

[0041] Figure 18 Schematic diagram of the installation of the tray with a trough for cable anchor dumping and the cable anchor.

[0042] Reference numerals: 1 - partial reaming bit, 1a1 - ground - down tooth, 1a0 - hole for ground - down tooth, 1t1 - drill pipe passage hole, 1a - first - order toothless disc, 1b - second - order toothed round platform, 1bb - toothed platform on the upper bottom surface of the second - order built - in round platform, 1c - third - order toothed round platform, 1cc - toothed platform on the upper bottom surface of the third - order built - in round platform, 2 - partial built - in surrounding - rock self - locking tray, 2a - first - order external part of the tray, 2b - second - order built - in round platform of the tray, 2c - third - order built - in round platform of the tray, 2t - cable - anchor passage hole, 2t1 - cable - anchor passage hole on the upper bottom surface of the tray, 2t2 - cable - anchor passage hole on the lower bottom surface of the tray, 2t0 - groove for cable - anchor tipping, 3 - drill pipe casing for fixed hole depth, 3a - drill pipe passage hole of the drill pipe casing for fixed hole depth, 4 - drill rig drive device, 4a - bolt, 5 - drill pipe, 6 - last section of drill pipe, 7 - surrounding rock, 8 - cable - anchor, 8a - cable - anchor borehole, 8b - anchoring section, 8c - wedge grip, 9a - ground - down area of the uneven surface of the surrounding rock, 9b - first - order reamed area of the surrounding rock, 9c - second - order reamed area of the surrounding rock;

[0043] The thickness H1 of the first - order toothless disc, the height H2 of the second - order toothed round platform, the angle β2 between the side surface and the upper bottom surface of the second - order toothed round platform, the height H3 of the third - order toothed round platform, the angle β3 between the side surface and the upper bottom surface of the third - order toothed round platform, the circumradius R0 of the polygon - ribbed hole, the upper - bottom - surface radius R3 of the third - order toothed round platform, the lower - bottom - surface radius R of the third - order toothed round platform 33 and the upper - bottom - surface radius R2 of the second - order toothed round platform, the lower - bottom - surface radius R of the second - order toothed round platform 22 and the radius R1 of the first - order toothless disc;

[0044] The thickness h1 of the first - order external part of the tray, the height h2 of the second - order built - in round platform of the tray, the angle α2 between the side surface and the upper bottom surface of the second - order built - in round platform of the tray, the height h3 of the third - order built - in round platform of the tray, the angle α3 between the side surface and the upper bottom surface of the third - order built - in round platform of the tray, the radius r0 of the cable - anchor passage hole 2t1 on the upper bottom surface of the tray, the upper - bottom - surface radius r3 of the third - order built - in round platform of the tray, the lower - bottom - surface radius r of the third - order built - in round platform of the tray 33 and the upper - bottom - surface radius r2 of the second - order built - in round platform of the tray, the lower - bottom - surface radius r of the second - order built - in round platform of the tray 22 and half of the width of the lower bottom surface of the tray r1, the angle α0 between the central axis of the cable - anchor passage hole of the tray and the lower bottom surface, the radius r of the cable - anchor passage hole 2t2 on the lower bottom surface of the tray 00 and the depth h0 of the groove for cable - anchor tipping. Specific Embodiment 1

[0046] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] The following describes the specific implementation of the present invention in detail with reference to specific embodiments.

[0048] Please refer to Figures 1 to 18 , a local built-in surrounding rock self-locking tray device provided by an embodiment of the present invention includes a local reaming bit 1, a local built-in surrounding rock self-locking tray 2, a casing 3, and a grinding tooth 1a1;

[0049] The local reaming bit 1 is a multi-stage variable-diameter bit, which are respectively a first-stage toothless disc 1a, a second-stage toothed frustum 1b, and a third-stage toothed frustum 1c. A hole 1a0 for grinding teeth is arranged on the first-stage toothless disc 1a. A drill pipe channel hole 1t1 is arranged inside the local reaming bit 1. The drill pipe channel hole 1t1 is a regular polygon and has the same cross-sectional shape as the drill pipe 5, so that the installation dimensions match;

[0050] The local built-in surrounding rock self-locking tray 2 is a multi-stage variable-diameter tray, which are respectively an outer part 2a of the first stage of the tray, an inner frustum 2b of the second stage of the tray, and an inner frustum 2c of the third stage of the tray;

[0051] The central axis of the cable anchor channel hole 2t of the local built-in surrounding rock self-locking tray 2 and the lower bottom surface of the local built-in surrounding rock self-locking tray 2 are preferably at an angle of 45° to 90°;

[0052] The inner frustum 2b of the second stage and the inner frustum 2c of the third stage of the local built-in surrounding rock self-locking tray 2 are in seamless and tight butt joint with the reaming area formed by the local reaming bit 1.

[0053] Further, the thickness of the first-stage toothless disc 1a of the local reaming bit 1 is preferably 1 to 3 cm; when the surface of the surrounding rock 7 is intact, the radius R1 of the first-stage toothless disc 1a is preferably 3 cm to 10 cm. When the surface of the surrounding rock 7 is incomplete and the abnormal contact between the local built-in surrounding rock self-locking tray 2 and the surrounding rock 7 affects the anchoring effect, the radius R1 of the first-stage toothless disc 1a is equal to half of the width r1 of the outer part 2a of the first stage of the local built-in surrounding rock self-locking tray 2.

[0054] Further, the height H2 of the second-stage toothed frustum 1b of the local reaming bit 1 is preferably 1 cm to 5 cm, the angle β2 between the side surface and the upper bottom surface of the second-stage toothed frustum 1b is preferably 45° to 90°, the radius R of the lower bottom surface of the second-stage toothed frustum 22 is preferably 3 cm to 10 cm, the radius R2 of the upper bottom surface of the second-stage toothed frustum is preferably 3 cm to 10 cm, and R2 < R 22 .

[0055] Further, the height H3 of the third-order toothed frustum 1c of the local reaming bit 1 should be 1 cm to 5 cm, the included angle β3 between the side surface of the third-order toothed frustum and the upper bottom surface should be 45° to 90°, and the radius R of the lower bottom surface of the third-order toothed frustum 33 should be 3 cm to 9 cm, the radius R3 of the upper bottom surface of the third-order toothed frustum should be 1 cm to 7 cm, and R3 < R 33 .

[0056] Further, the thickness h1 of the first-order external part 2a of the tray of the local built-in surrounding rock self-locking tray 2 should be 1 cm to 4 cm, the shape of the first-order external part 2a of the tray is square or circular, and half of the width r1 of the first-order external part 2a of the tray should be 10 cm to 30 cm.

[0057] Further, the height h2 of the second-order internal frustum 2b of the tray of the local built-in surrounding rock self-locking tray 2 should be 1 cm to 5 cm, the included angle α2 between the side surface of the second-order internal frustum and the upper bottom surface should be 45° to 90°, and the radius r of the lower bottom surface of the second-order internal frustum 22 should be 3 cm to 10 cm, the radius r2 of the upper bottom surface of the second-order internal frustum should be 3 cm to 10 cm, and r2 < r 22 .

[0058] Further, the height h3 of the third-order internal frustum 2c of the tray of the local built-in surrounding rock self-locking tray 2 should be 1 cm to 5 cm, the included angle α3 between the side surface of the third-order internal frustum and the upper bottom surface should be 45° to 90°, and the radius r of the lower bottom surface of the third-order internal frustum 33 should be 3 cm to 9 cm, the radius r3 of the upper bottom surface of the third-order internal frustum should be 1 cm to 7 cm, and r3 < r 33 ; H2 = h2, H3 = h3, R3 = r3 < R 33 = r 33 ≤ R2 = r2 < R 22 = r 22 < r1, α3 = β3, α2 = β2.

[0059] Further, the teeth of the grinding teeth 1a1 should be flush with the upper side surface of the first-order toothless disc 1a to achieve grinding only the protruding tips of the surrounding rock.

[0060] A method for using a local built-in surrounding rock self-locking tray device specifically includes the following steps:

[0061] Step 1. Select the model of the local built-in surrounding rock self-locking tray 2:

[0062] The included angle between the cable anchor hole 8a and the bedding plane of the surrounding rock 7 is The included angle between the central axis of the tray cable anchor channel hole and the lower bottom surface is α0, satisfying is appropriate. Below the surrounding rock 7 is the flattened area 9a of the uneven surface of the surrounding rock, and below the cable anchor hole 8a is the flattened area 9a of the uneven surface of the surrounding rock and the first-stage reaming area 9b of the surrounding rock;

[0063] When a hydraulic support, a unit support, etc. are repeatedly supported in the designed anchorage section, there is a cable anchor dumping groove 2t0 on the first-stage built-in disc 2a of the tray, and the central axis of the cable anchor dumping groove 2t0 is parallel to the support advancing direction; it is appropriate that the volume space of the cable anchor dumping groove 2t0 per unit length is basically equal to the volume of the cable anchor under the condition of per unit length;

[0064] Step 2: Determine the length of the casing 3. The length of the casing 3 is equal to the length of the last drill pipe 6 minus the depth that the last drill pipe 6 is designed to drill and minus the thickness of the first-stage toothless disc 1a;

[0065] Step 3: When the cable anchor hole is drilled to the last drill pipe 6, while connecting the last drill pipe 6, successively put the local reaming bit 1 and the casing 3 on the last drill pipe 6;

[0066] Step 4: Use the drill rig transmission device 4 and the casing 3 to drill the local reaming bit 1 into the cable anchor hole 8a. After drilling to the specified depth, that is, when the first-stage toothless disc 1a is close to the surface of the surrounding rock 7, continue to rotate until the uneven surrounding rock surface is ground flat by the grinding teeth 1a1 and then stop drilling. Among them, the drill rig transmission device 4 is connected to the last drill pipe 6 through bolts 4a;

[0067] Step 5: Finally, install the selected local built-in surrounding rock self-locking tray 2, cable anchor 8 and wedge anchor 8c, and tension them to the designed pre-tightening force.

[0068] The above method is also applicable to rock bolts;

[0069] The above parameters are not limited to the above parameters.

[0070] The geological conditions of a certain mine: The roof of a strongly mined goaf roadway is uneven, and it is difficult to exert the cable anchor support performance. At the same time, in the middle area of the roadway, a mobile unit support and a large-range advanced support are required to repeatedly support the roof, which will cause the damage of the anchor fittings arranged in the middle area and the failure of the cable anchor support. The design requires that the included angle between the cable anchors on both sides of the roadway close to the rib and the roadway roof is 75°, and the cable anchors in the middle area of the roadway are arranged perpendicular to the roof.

[0071] The specific usage method is as follows:

[0072] (1) Select the tray and bit models:

[0073] For the local built-in surrounding rock self-locking tray 2, r1 = 15 cm, h1 = 3 cm, r22 = 4 cm, h2 = 3 cm, r2 = 3 cm, r 33 = 2 cm, h3 = 2 cm, r3 = 1.5 cm; The α0 of the local built-in surrounding rock self-locking tray 2 for the anchor cable 8 arranged on both sides of the roadway is 75°, the α0 of the local built-in surrounding rock self-locking tray 2 for the anchor cable 8 arranged in the middle of the roadway is 90°, and h0 is 1 cm. The installation direction of 2t0 is parallel to the support movement direction;

[0074] For the drill bit 1, R1 = 15 cm, R1 = 2 cm, R 22 = 4 cm, H2 = 3 cm, R2 = 3 cm, R 33 = 2 cm, H3 = 2 cm, R3 = 1.5 cm. A number of grinding teeth 1a1 are arranged on the first-stage toothless disc 1a of the drill bit 1;

[0075] (2) Determine the length of the casing 3: The length of the casing 3 is equal to the length of the last drill pipe 6 minus the depth that the last drill pipe 6 is designed to drill and minus the thickness of the first-stage toothless disc 1a;

[0076] (3) When the anchor cable borehole 8a drills to the last drill pipe 6, while connecting the last drill pipe 6, successively put the local reaming drill bit 1 and the casing 3 on the last drill pipe 6;

[0077] (4) After drilling to the specified depth, that is, when the first-stage toothless disc 1a is close to the surface of the surrounding rock 7, continue to rotate until the grinding teeth 1a1 grind the uneven surface of the surrounding rock 7 and then stop drilling;

[0078] (5) Finally, install the selected local built-in surrounding rock self-locking tray 2, anchor cable 8 and wedge anchor 8c, and tension to the designed pre-tightening force. Specific Embodiment 2

[0080] Geological conditions of a certain mine: The roof of a strongly mined goaf roadway is flat. In the middle area of the roadway, a mobile unit support and a large-range advanced support are required to repeatedly support the roof, which will cause damage to the anchor fittings arranged in the middle area and failure of the anchor cable support. The design requires that the included angle between the anchor cables on both sides of the roadway and the roof of the roadway is 75°, and the anchor cables 8 in the middle area of the roadway are arranged perpendicular to the roof. The method of the present invention is used:

[0081] Since the roof is intact and there is no need to grind the roof, R1 of the drill bit 1 is 5 cm, and the first-stage toothless disc 1a of the drill bit 1 does not need to be arranged with grinding teeth 1a1.

[0082] Other parts of the structure in this embodiment are the same as those in Specific Embodiment 1.

[0083] The method of the present invention does not require the tray to be installed with additional anchors. It has good force-bearing performance through multi-stage variable diameter, strong overall bearing capacity, and a stable and reliable tray support system that is not affected by repeated supports such as brackets and is not damaged. It has strong adaptability, and the drilling and reaming are integrated into one forming, which is convenient and fast, and has very wide and important popularization and application value.

[0084] The purpose of the present invention is to solve the problems existing in the traditional method of anchoring the anchor and the tray, such as the uneven force between the anchor and the tray, the inability to effectively adapt to the non-uniform load problem when the anchor cable is inclined, the anchor occupying the roadway space, the easy damage of the anchor under the long-term external corrosion environment and the mechanical external force of the external anchor, and the uneven stress concentration and extremely unbalanced force between the tray and the anchor due to the uneven surface of the surrounding rock, which will lead to failure. Increasing the size and strength of the anchor and the tray cannot fundamentally solve the above problems, which is not only economically unreasonable but also limited in effect. By providing a locally built-in surrounding rock self-locking tray device and its using method, the locally built-in surrounding rock tray does not require the installation of additional anchors, so it can be not restricted by any performance of the anchor. When the anchor cable is installed obliquely, it can well balance the eccentric load, so that the anchor cable is not affected by high shear force. At the same time, it has good structural force-bearing performance, strong overall bearing capacity, a stable and reliable tray support system that is not affected by repeated supports such as brackets and is not damaged. It has strong adaptability, and the drilling and reaming of the anchor cable are integrated into one forming, which is convenient and fast, and has very wide and important popularization and application value.

[0085] For those skilled in the art, although several embodiments and examples of the present invention are described, these embodiments and examples are presented as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and its equivalents.

[0086] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A locally built-in surrounding rock self-locking tray device, characterized in that, It includes a local reaming bit (1), a local built-in surrounding rock self-locking tray (2), a casing (3), and a grinding tooth (1a1); The local reaming bit (1) is a multi-stage variable-diameter bit, which are respectively a first-stage toothless disc (1a), a second-stage toothed frustum (1b), and a third-stage toothed frustum (1c). A hole (1a0) for grinding teeth is arranged on the first-stage toothless disc (1a). A drill pipe channel hole (1t1) is arranged inside the local reaming bit (1). The drill pipe channel hole (1t1) is a regular polygon and has the same cross-sectional shape as the drill pipe (5); The local built-in surrounding rock self-locking tray (2) is a multi-stage variable-diameter tray, which are respectively an outer part of the first stage of the tray (2a), an inner frustum of the second stage of the tray (2b), and an inner frustum of the third stage of the tray (2c); The included angle between the central axis of the cable anchor channel hole (2t) of the local built-in surrounding rock self-locking tray (2) and the lower bottom surface of the local built-in surrounding rock self-locking tray (2) is 45° - 90°; The inner frustum of the second stage (2b) and the inner frustum of the third stage (2c) of the local built-in surrounding rock self-locking tray (2) are in seamless and tight butt joint with the reaming area formed by the local reaming bit (1); The local reaming bit (1) and the casing (3) are successively sleeved on the last drill pipe (6). The local reaming bit (1) is drilled into the cable anchor hole (8a) by using the drill rig transmission device (4) and the casing (3). When drilling to the point where the first-stage toothless disc (1a) is close to the surface of the surrounding rock (7), continue to rotate until the grinding tooth (1a1) grinds the uneven surface of the surrounding rock and then stop drilling.

2. The partial built-in surrounding rock self-locking tray device according to claim 1, characterized in that, The thickness of the first-stage toothless disc (1a) of the local reaming bit (1) is 1 cm - 3 cm; when the surface of the surrounding rock (7) is intact, the radius R1 of the first-stage toothless disc (1a) is 3 cm - 10 cm. When the surface of the surrounding rock (7) is incomplete and the abnormal contact between the local built-in surrounding rock self-locking tray (2) and the surrounding rock (7) affects the anchoring effect, the radius R1 of the first-stage toothless disc (1a) is equal to half of the width r1 of the outer part of the first stage of the local built-in surrounding rock self-locking tray (2).

3. The locally built-in surrounding rock self-locking tray device according to claim 2, characterized in that, The height H2 of the second toothed frustum (1b) of the partial reaming bit (1) is 1 cm to 5 cm, the included angle β2 between the side surface and the upper bottom surface of the second toothed frustum (1b) is 45° to 90°, the radius R of the lower bottom surface of the second toothed frustum 22 is 3 cm to 10 cm, the radius R2 of the upper bottom surface of the second toothed frustum is 3 cm to 10 cm, and R2 < R 22 .

4. The locally built-in surrounding rock self-locking tray device according to claim 3, characterized in that, The height H3 of the third toothed frustum (1c) of the partial reaming bit (1) is 1 cm to 5 cm, the included angle β3 between the side surface of the third toothed frustum and the upper bottom surface is 45° to 90°, the radius R of the lower bottom surface of the third toothed frustum 33 is 3 cm to 9 cm, the radius R3 of the upper bottom surface of the third toothed frustum is 1 cm to 7 cm, and R3 < R 33 .

5. The locally built-in surrounding rock self-locking tray device according to claim 4, characterized in that, The thickness h1 of the outer part of the first stage of the tray (2a) of the local built-in surrounding rock self-locking tray (2) is 1 cm - 4 cm. The shape of the outer part of the first stage of the tray (2a) is square or circular. Half of the width r1 of the outer part of the first stage of the tray (2a) is 10 cm - 30 cm.

6. A locally built-in surrounding rock self-locking tray device according to claim 5, characterized in that, The height h2 of the second-stage built-in conical platform (2b) of the locally built-in surrounding rock self-locking tray (2) is 1 cm to 5 cm, the included angle α2 between the side surface and the upper bottom surface of the second-stage built-in conical platform of the tray is 45° to 90°, and the radius r of the lower bottom surface of the second-stage built-in conical platform of the tray 22 is 3 cm to 10 cm, the radius r2 of the upper bottom surface of the second-stage built-in conical platform is 3 cm to 10 cm, and r2 < r 22 .

7. The partial built-in surrounding rock self-locking tray device according to claim 6, characterized in that, The height h3 of the third-order built-in conical platform (2c) of the local built-in surrounding rock self-locking tray (2) is 1 cm to 5 cm, the included angle α3 between the side surface and the upper bottom surface of the third-order built-in conical platform of the tray is 45° to 90°, and the radius r of the lower bottom surface of the third-order built-in conical platform of the tray 33 is 3 cm to 9 cm, the radius r3 of the upper bottom surface of the third-order built-in conical platform is 1 cm to 7 cm, and r3 < r 33 ; H2 = h2, H3 = h3, R3 = r3 < R 33 = r 33 ≤ R2 = r2 < R 22 = r 22 < r1, α3 = β3, α2 = β 2。 8. A method for using a local built-in surrounding rock self-locking tray device, which is applied to a local built-in surrounding rock self-locking tray device as described in any one of claims 1 - 7. The specific steps include: Step 1: Select the model of the local built-in surrounding rock self-locking tray (2): The included angle between the cable anchor hole (8a) and the bedding plane of the surrounding rock (7) is The included angle between the central axis of the tray cable anchor passage hole and the lower bottom surface of the tray is α0, The minimum value of which is 0° and the maximum value is 2°; A cable anchor dumping groove (2t0) is arranged on the outer part of the first stage of the tray (2a). The volume space of the cable anchor dumping groove (2t0) per unit length is basically equal to the volume of the cable anchor (8) under the condition of per unit length; Step 2: Determine the length of the casing (3). The length of the casing (3) is equal to the length of the last drill pipe (6) minus the depth that the last drill pipe (6) is designed to drill and minus the thickness of the first-stage toothless disc (1a). Step 3: When the anchor cable borehole is drilled to the last drill pipe (6), while connecting the last drill pipe (6), successively slip on the local hole enlarging bit (1) and the casing (3) on the last drill pipe (6). Step 4: After drilling to the designated depth, that is, when the first-stage toothless disc (1a) is in close contact with the surface of the surrounding rock (7), continue to rotate until the grinding teeth (1a1) grind the uneven surface of the surrounding rock flat and then stop drilling. Step 5: Finally, install the selected local built-in surrounding rock self-locking tray (2), anchor cable (8) and wedge (8c), and tension them to the designed pre-tightening force.

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