A kind of rock retaining support device and method for deep mining top cutting and gob retaining side of gob

Abstract

The invention discloses a device and method for supporting the goaf of deep mining and top cutting along the goaf retaining lane, comprising a plurality of anti-collision support devices, the plurality of anti-collision support devices are arranged side by side, and a flexible metal mesh is arranged between two adjacent anti-collision support devices; the anti-collision support device comprises a first-level support, a second-level support, a third-level support, an upper support plate, a lower support plate, a steel drill and three fixed rings; the first-level support, the second-level support and the third-level support are all hollow cylindrical cylinders; the first-level support, the second-level support and the third-level support are arranged coaxially from bottom to top. When subjected to the impact of high mining pressure, it has good vertical yielding and pressure relief performance, so that it can adapt to the large deformation of the surrounding rock of the deep strong mining lane, and can have good lateral pressure resistance, maintain the stability of the goaf wall, and finally make the goaf area goaf form an effective support for the overlying roof.

Description

Technical Field

[0001] The invention relates to a gangue retaining and supporting device and method for gangue walls of coal tunnels, in particular to a gangue retaining and supporting device and method for the goaf side of deep mining and top cutting goaf-side tunneling. Background Art

[0002] As a non-renewable resource, the sustainable development of coal is increasingly valued by people. Under the existing technical conditions, in order to recover more coal, the pace of promoting the non-pillar mining method has gradually increased. As the basis for the promotion of the non-pillar mining method, gob-side entry retention has also been widely used. Gob-side entry retention technology is a major coal-pillar-free mining method, which not only improves the resource recovery rate, but also avoids geological disasters caused by the stress concentration of coal pillars. It is one of the main directions of green coal mining and sustainable development. The final stability of the gob-side entry retention after top cutting is actually determined by the solid coal wall and the goaf gangue. Therefore, the stability of the gangue wall is also of great significance. In the early stage of gob-side entry retention after top cutting, the roof moves violently, and the goaf roof has not collapsed fully, so it cannot form an effective support for the overlying rock strata, and the anchor (cable) support structure cannot achieve self-stabilization under the action of lateral roof fracture and sinking. In order to reduce the impact of roof movement on the tunnel and maintain the stability of the surrounding rock of the tunnel, auxiliary reinforcement support must be carried out in the tunnel, especially on the side of the goaf. After the overburden movement of the tunnel along the goaf is completed and the gangue in the goaf forms an effective support for the overburden, the surrounding rock of the tunnel along the goaf tends to be stable, and the temporary reinforcement support in the tunnel can be removed. The rigid retaining rock support is mainly caused by the bending failure caused by the vertical deformation and extrusion of the deep surrounding rock. The lateral horizontal thrust of the gangue in the goaf on the retaining rock structure is not the main factor of its destruction.

[0003] Rigid devices are often used for side rock retaining support in gob-side tunneling. However, the stress in deep tunnels is high and the dynamic pressure influence is significantly increased. Rigid rock retaining support often bends and breaks due to the inability to adapt to the large deformation of deep surrounding rock, thus losing the ability to retain rock and causing failure of tunneling. The existing rock retaining support devices mostly use anchor rods and other steel frame structures. Due to the instability of the goaf top cutting and the excessive lateral stress in the goaf, the rock retaining is deformed, which cannot meet the requirements of the deep underground environment. The fixed specifications cannot be applied to the complex tunnel environment, and the flexibility is insufficient. In addition, the deep stress environment is complex. When the stress in the goaf is too large, it is easy to cause the support structure to be unstable and deformed, which threatens the gob-side tunneling. Therefore, it is necessary to study a support device suitable for complex stress environments, so that it has a certain degree of vertical displacement and pressure relief, so that it can adapt to the deformation of deep surrounding rock, and has a good ability to resist lateral pressure, maintain the stability of the rock wall, and finally make the goaf rock form an effective support for the overlying roof. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, the present invention provides a gangue retaining support device and method for the goaf side of deep mining and top cutting and goaf retaining. When subjected to the impact of ground stress, it has a certain degree of vertical yielding and pressure relief, thereby being able to adapt to the deformation of deep surrounding rock, and has good lateral pressure resistance, maintaining the stability of the gangue wall, and ultimately enabling the gangue in the goaf area to form effective support for the overlying roof.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a rock retaining support device for the gob side of deep mining top cutting and gob retaining lane, comprising a plurality of anti-collision support devices, the plurality of anti-collision support devices are arranged side by side, and a flexible metal mesh is arranged between two adjacent anti-collision support devices;

[0006] The anti-collision support device comprises a first-level support, a second-level support, a third-level support, an upper support plate, a lower support plate, a steel chisel and three fixed rings; the first-level support, the second-level support and the third-level support are all hollow cylindrical cylinders; the first-level support, the second-level support and the third-level support are coaxially arranged in sequence from bottom to top, wherein the second-level support is arranged in the first-level support and can be extended and retracted relative to the first-level support, and the first-level support and the second-level support are relatively fixed by a fastening bolt I arranged on the side of the first-level support; the third-level support is arranged in the second-level support and can be extended and retracted relative to the second-level support, and the third-level support is .... The first-level pillar and the second-level pillar are relatively fixed by a fastening bolt II arranged on the side of the second-level pillar; the upper support plate is fixed to the top of the third-level pillar, and the lower support plate is fixed to the bottom of the first-level pillar and is parallel to the upper support plate; the steel drill is coaxially arranged below the first-level pillar, and the upper end of the steel drill is fixedly connected to the lower part of the lower support plate; the three fixed joint rings are respectively fixed to the side of the first-level pillar, the side of the second-level pillar and the side of the third-level pillar, and a card slot is respectively provided on the same side of the three fixed joint rings, and two adjacent fixed joint rings are fixedly connected by an arched anti-impact energy absorption joint;

[0007] Two adjacent anti-collision support devices are fixedly connected by reinforcing ribs, and the two ends of the reinforcing ribs are respectively inserted into the slots of the two anti-collision support devices for fixation; a strong hook is provided on the flexible metal net, and the flexible metal net is fixed to the side of the reinforcing rib by the strong hook.

[0008] Furthermore, the frictional resistance formed between the second-level support and the third-level support is greater than the frictional resistance formed between the first-level support and the second-level support. Such a setting based on the temporal and spatial evolution law of mining pressure can make the device have better anti-impact performance and pressure relief capacity, thereby ensuring the stability of the support.

[0009] Furthermore, the upper support plate and the top of the level III pillar, the lower support plate and the bottom of the level I pillar, the upper end of the steel drill and the lower part of the lower support plate, and the end of the reinforcing rib and the slot are all fixedly connected by welding. Welding is not only convenient for construction, but also can effectively ensure the stability of the connection, and ultimately ensure the stability of the support and surrounding rock.

[0010] A supporting method for a rock retaining support device on the gob side of a deep mining top cutting gob retaining roadway, the specific process is:

[0011] Step 1: When the goaf side of the tunnel is used for rock support, a row of holes matching the steel drills are drilled at equal intervals along the axial direction of the tunnel on the goaf side, and then the steel drills of each anti-collision support device are respectively inserted into each hole until the lower support plate fits with the bottom plate of the tunnel, and finally the holes are filled to fix the steel drills in the holes;

[0012] Step 2: According to the height of the tunnel, first loosen the fastening bolts I, extend the level II pillars from the level I pillars to a certain length, and then tighten the fastening bolts I to make the level I pillars and the level II pillars relatively fixed; then loosen the fastening bolts II, extend the level III pillars from the level II pillars to a certain length, so that the upper support plate fits with the top plate of the tunnel, and then tighten the fastening bolts II to make the level III pillars and the level II pillars relatively fixed; according to the distribution of stress, it is concluded that the stress required at the top is greater than that at the bottom, so the fastening force of the fastening bolts II is greater than the fastening force of the fastening bolts I, so that the frictional resistance formed between the level III pillars and the level II pillars is greater than the frictional resistance formed between the level I pillars and the level II pillars;

[0013] Step 3: fix the three fixed joint rings to the side of the first-level pillar, the side of the second-level pillar and the side of the third-level pillar respectively, and then fix and connect two adjacent fixed joint rings through the arched anti-impact energy absorption joint;

[0014] Step 4: Three reinforcing ribs are used to connect two adjacent anti-collision support devices. The two ends of each reinforcing rib are respectively inserted into the corresponding slots of the two anti-collision support devices and welded. Finally, a flexible metal mesh 10 is hung between the two adjacent anti-collision support devices. The flexible metal mesh is fixed to the side of the reinforcing rib by a strong hook. After a row of laying is completed, it can block the lateral movement of the gangue on the goaf side of the tunnel and maintain the stability of the gangue side.

[0015] Compared with the prior art, the present invention adopts a combination of an anti-collision support device and a flexible metal mesh, wherein the anti-collision support device includes a level I pillar, a level II pillar, a level III pillar, an upper support plate, a lower support plate, a steel chisel and three fixed-joint rings; during the support process, if subjected to vertical deformation extrusion caused by deep surrounding rock ground stress, if the vertical extrusion force is less than the sum of the friction resistance formed between the level I pillar and the level II pillar and the elastic deformation force of the arched anti-collision energy-absorbing joint between the two pillars, the anti-collision support device can achieve a stable support effect; if the vertical extrusion force is greater than or equal to the sum of the friction resistance formed between the level I pillar and the level II pillar and the elastic deformation force of the arched anti-collision energy-absorbing joint between the two pillars, the level II pillar partially retracts into the level I pillar, and at the same time, the arched anti-collision energy-absorbing joint between the level I pillar and the level II pillar undergoes elastic deformation to increase the elastic force, thereby increasing The overall supporting force of the large anti-collision support device can buffer and relieve pressure on the extrusion impact; until the vertical extrusion pressure is less than the friction resistance formed between the level I pillar and the level II pillar and the elastic deformation force of the arched anti-impact energy-absorbing joint between the two pillars, the tunnel can be stably supported at this time; if the level II pillar partially retracts into the level I pillar, the vertical extrusion pressure continues to increase, when it is greater than or equal to the sum of the friction resistance formed between the level II pillar and the level III pillar and the elastic deformation force of the arched anti-impact energy-absorbing joint between the two pillars, the level III pillar will partially retract into the level II pillar, and at the same time, the arched anti-impact energy-absorbing joint between the level II pillar and the level III pillar will undergo elastic deformation to increase the elastic force, thereby further increasing the overall supporting force of the anti-impact support device, and further buffering and pressure-relieving support for the extrusion impact; until the vertical extrusion pressure and supporting force are stable, stable support is achieved. In addition, when the flexible metal mesh is subjected to lateral pressure from the gangue, it can transfer the lateral force to the fixed joint ring through the strong ribs, and then the fixed joint ring transfers the force to the arched anti-impact energy-absorbing joint, and the arched anti-impact energy-absorbing joint buffers and relieves the lateral force through partial deformation. Therefore, the present invention has a certain degree of vertical yielding and pressure relief when subjected to ground stress impact, so that it can adapt to the deformation of deep surrounding rocks, and can have a good ability to resist lateral pressure, maintain the stability of the gangue wall, and finally make the gangue in the goaf form an effective support for the overlying roof. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the anti-collision support device in the present invention;

[0017] Figure 2 It is a structural schematic diagram of the arched anti-impact energy absorbing joint in the present invention;

[0018] Figure 3 This is a schematic diagram of the structure of the fixed pitch ring and the slot in the present invention.

[0019] Figure 4 It is a schematic diagram of the overall structure of the present invention after assembly.

[0020] In the figure: 1. Level I pillar, 2. Level II pillar, 3. Level III pillar, 4. Fastening bolt II, 5. Upper support plate, 6. Lower support plate, 7. Steel chisel, 8. Fixed joint ring, 81. Slot, 9. Strengthening rib, 10. Flexible metal mesh, 11. Arched anti-impact energy absorption joint, 12. Strong hook. DETAILED DESCRIPTION

[0021] The present invention will be further described below.

[0022] like Figures 1 to 4 As shown, a rock retaining support device for deep mining top cutting and gob retaining side of gob, comprising a plurality of anti-collision support devices, the plurality of anti-collision support devices are arranged side by side, and a flexible metal mesh 10 is arranged between two adjacent anti-collision support devices;

[0023] The anti-collision support device comprises a first-level pillar 1, a second-level pillar 2, a third-level pillar 3, an upper support plate 5, a lower support plate 6, a steel chisel 7 and three fixed rings 8; the first-level pillar 1, the second-level pillar 2 and the third-level pillar 3 are all hollow cylindrical cylinders; the first-level pillar 1, the second-level pillar 2 and the third-level pillar 3 are coaxially arranged in sequence from bottom to top, wherein the second-level pillar 2 is arranged in the first-level pillar 1 and can be extended and retracted relative to the first-level pillar 1, and the first-level pillar 1 and the second-level pillar 2 are relatively fixed by a fastening bolt I arranged on the side of the first-level pillar 1; the third-level pillar 3 is arranged in the second-level pillar 2 and can be extended and retracted relative to the second-level pillar 2, and the third-level pillar 3 is arranged in the second-level pillar 2 and can be extended and retracted relative to the second-level pillar 2. The first-level pillar 3 and the second-level pillar 2 are relatively fixed by fastening bolts II4 arranged on the side of the second-level pillar 2; the upper support plate 5 is fixed to the top of the third-level pillar 3, and the lower support plate 6 is fixed to the bottom of the first-level pillar 1 and is parallel to the upper support plate 5; the steel drill 7 is coaxially arranged below the first-level pillar 1, and the upper end of the steel drill 7 is fixedly connected to the lower part of the lower support plate 6; the three fixed joint rings 8 are respectively fixed to the side of the first-level pillar 1, the side of the second-level pillar 2 and the side of the third-level pillar 3, and a card slot 81 is respectively provided on the same side of the three fixed joint rings 8, and two adjacent fixed joint rings 8 are fixedly connected by an arched anti-impact energy absorption joint 11;

[0024] Two adjacent anti-collision support devices are fixedly connected by reinforcing ribs 9, and the two ends of the reinforcing ribs 9 are respectively inserted into the slots 81 of the two anti-collision support devices for fixation; a strong hook 12 is provided on the flexible metal mesh 10, and the flexible metal mesh 10 is fixed to the side of the reinforcing rib 9 by the strong hook 12.

[0025] Furthermore, the frictional resistance formed between the second-level pillar 2 and the third-level pillar 3 is greater than the frictional resistance formed between the first-level pillar 1 and the second-level pillar 2. According to the distribution of stress, it is concluded that the stress required at the top is greater than that at the bottom. Therefore, such a setting can make the device more impact-resistant, thereby ensuring the stability of the support.

[0026] Furthermore, the upper support plate 5 and the top of the level III pillar 3, the lower support plate and the bottom of the level I pillar 1, the upper end of the steel drill 7 and the lower part of the lower support plate 6, and the end of the reinforcing rib 9 and the slot 81 are all fixedly connected by welding. Welding is not only convenient for construction, but also can effectively ensure the stability of the connection, and ultimately ensure the stability of the support.

[0027] The above-mentioned level I pillar 1, level II pillar 2, level III pillar 3, upper support plate 5, lower support plate 6, steel chisel 7, fixed joint ring 8 and arched anti-impact energy absorption joint 11 are all existing components.

[0028] A supporting method for a rock retaining support device on the gob side of a deep mining top cutting gob retaining roadway, the specific process is:

[0029] Step 1: When the goaf side of the tunnel is used for the rock retaining support, a row of holes matching the steel drill 7 are drilled at equal intervals along the axial direction of the tunnel on the goaf side, and then the steel drills 7 of each anti-collision support device are respectively inserted into each hole until the lower support plate 6 is cut into the bottom plate of the tunnel, and finally the holes are filled to fix the steel drill 7 in the holes;

[0030] Step 2: According to the height of the tunnel, first loosen the fastening bolts I, extend the level II pillar 2 from the level I pillar 1 to a certain length, and then tighten the fastening bolts I to make the level I pillar 1 and the level II pillar 2 relatively fixed; then loosen the fastening bolts II4, extend the level III pillar 3 from the level II pillar 2 to a certain length, so that the upper support plate 5 fits with the top plate of the tunnel, and then tighten the fastening bolts II4 to make the level III pillar 3 and the level II pillar 2 relatively fixed; according to the distribution of stress, it is concluded that the stress required at the top is greater than that at the bottom, so the fastening force of the fastening bolts II4 is greater than the fastening force of the fastening bolts I, so that the frictional resistance formed between the level III pillar 3 and the level II pillar 2 is greater than the frictional resistance formed between the level I pillar 1 and the level II pillar 2;

[0031] Step 3: fix three fixed joint rings 8 to the side of the first-level pillar 1, the side of the second-level pillar 2 and the side of the third-level pillar 3 respectively, and then fix two adjacent fixed joint rings 8 through the arched anti-impact energy absorption joint 11;

[0032] Step 4: Three reinforcing ribs 9 are used to connect two adjacent anti-collision support devices. The two ends of each reinforcing rib 9 are respectively inserted into the corresponding slots 81 of the two anti-collision support devices and welded. Finally, a flexible metal mesh 10 is hung between the two adjacent anti-collision support devices. The flexible metal mesh 10 is fixed to the side of the reinforcing rib 9 by a strong hook 12. After a row of laying is completed, it can block the lateral movement of the gangue on the side of the goaf of the tunnel and maintain the stability of the gangue side.

Claims

1. A rock retaining support device for the gob side of deep mining and top cutting gob retaining, characterized in that: It comprises a plurality of anti-collision support devices, the plurality of anti-collision support devices are arranged side by side, and a flexible metal mesh is arranged between two adjacent anti-collision support devices; The anti-collision support device includes a level I pillar, a level II pillar, a level III pillar, an upper support plate, a lower support plate, a steel chisel and three fixed rings; the level I pillar, the level II pillar and the level III pillar are all hollow cylindrical cylinders; the level I pillar, the level II pillar and the level III pillar are coaxially arranged in sequence from bottom to top, wherein the level II pillar is arranged in the level I pillar and can be extended and retracted relative to the level I pillar, and the level I pillar and the level II pillar are relatively fixed by a fastening bolt I arranged on the side of the level I pillar; the level III pillar is arranged in the level II pillar and can be extended and retracted relative to the level II pillar, and the level III pillar and the level II pillar are fixed by a fastening bolt I arranged on the side of the level I pillar The fastening bolts II on the side are relatively fixed; the upper support plate is fixed to the top of the III-level pillar, and the lower support plate is fixed to the bottom of the I-level pillar and is parallel to the upper support plate; the steel drill is coaxially arranged below the I-level pillar, and the upper end of the steel drill is fixedly connected to the lower part of the lower support plate; the three fixed joint rings are respectively fixed to the side of the I-level pillar, the side of the II-level pillar and the side of the III-level pillar, and a slot is provided on the same side of the three fixed joint rings, and two adjacent fixed joint rings are fixedly connected by an arched anti-impact energy absorption joint; the friction resistance formed between the II-level pillar and the III-level pillar is greater than the friction resistance formed between the I-level pillar and the II-level pillar; Two adjacent anti-impact support devices are fixedly connected by reinforcing ribs, and the two ends of the reinforcing ribs are respectively inserted into the slots of the two anti-impact support devices for fixation; a strong hook is provided on the flexible metal mesh, and the flexible metal mesh is fixed to the side of the reinforcing rib by the strong hook; the upper support plate and the top end of the level III pillar, the lower support plate and the bottom end of the level I pillar, the upper end of the steel chisel and the lower part of the lower support plate, and the end of the reinforcing rib and the slot are fixedly connected by welding.

2. A method for supporting the rock retaining support device at the gob side of deep mining top cutting and gob retaining according to claim 1, characterized in that: The specific process is: Step 1: When the goaf side of the tunnel is used for rock support, a row of holes matching the steel drills are drilled at equal intervals along the axial direction of the tunnel on the goaf side, and then the steel drills of each anti-collision support device are respectively inserted into each hole until the lower support plate fits with the bottom plate of the tunnel, and finally the holes are filled to fix the steel drills in the holes; Step 2: According to the height of the tunnel, first loosen the fastening bolts I, extend the level II pillars from the level I pillars to a certain length, and then tighten the fastening bolts I to make the level I pillars and the level II pillars relatively fixed; then loosen the fastening bolts II, extend the level III pillars from the level II pillars to a certain length, so that the upper support plate fits with the top plate of the tunnel, and then tighten the fastening bolts II to make the level III pillars and the level II pillars relatively fixed; and make the fastening force of the fastening bolts II greater than the fastening force of the fastening bolts I, so that the frictional resistance formed between the level III pillars and the level II pillars is greater than the frictional resistance formed between the level I pillars and the level II pillars; Step 3: fix the three fixed joint rings to the side of the first-level pillar, the side of the second-level pillar and the side of the third-level pillar respectively, and then fix and connect two adjacent fixed joint rings through the arched anti-impact energy absorption joint; Step 4: Three reinforcing ribs are used to connect two adjacent anti-impact support devices. The two ends of each reinforcing rib are inserted into the corresponding slots of the two anti-impact support devices and welded. Finally, a flexible metal mesh is hung between the two adjacent anti-impact support devices. The flexible metal mesh is fixed to the side of the reinforcing rib by a strong hook. After a row of laying is completed, it can block the lateral movement of the gangue on the goaf side of the tunnel and maintain the stability of the gangue side.

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