In-situ method of applying confining pressure for anchoring surrounding rock

Abstract

The present application relates to the technical field of anchoring support, and provides a confining pressure in-situ application method for anchoring surrounding rock, which comprises the following steps: arranging an anchoring part in a to-be-supported area, wherein the to-be-supported area is a roadway roof or roadway side; arranging a water injection expander in a sparse area in the to-be-supported area, wherein the sparse area is determined according to the number of anchoring parts arranged in a unit area in the to-be-supported area; and water is supplied to the water injection expander to pressurize it, so that the pre-tightening force of each anchoring part close to the water injection expander is equal to a target pre-tightening force. In order to improve the anchoring effect of the shallow surrounding rock, the water injection expander is arranged in the sparse area in the to-be-supported area, and water is supplied to the water injection expander to pressurize it, so that the in-situ indirect application of the tangential confining pressure of the shallow surrounding rock can be realized, the pre-tightening force of the anchor rod can be compensated and increased, the formation of a stable anchoring structure can be promoted, the anchoring effect of the anchor rod can be improved, and the method can be used as a new type of roadway support technology and means and widely applied to coal mine roadway support engineering.

Description

Technical Field

[0001] This invention relates to the field of anchoring support technology, and in particular to a method for in-situ application of confining pressure for anchoring surrounding rock. Background Technology

[0002] Rock bolt support is commonly used in coal mine roadways. In actual engineering, due to plastic failure of the shallow surrounding rock, tangential concentrated stress is transferred to the deeper parts of the surrounding rock, resulting in a low confining pressure state for the shallow surrounding rock, which is precisely the target of rock bolt support. Engineering practice and laboratory tests both show that when using rock bolt support to reinforce shallow surrounding rock, increasing the tangential confining pressure is extremely important for forming a stable anchoring structure and improving the support effect. In actual roadway engineering, the shallow surrounding rock only exists at the roadway free face, making it impossible to apply tangential confining pressure to the shallow surrounding rock through the free face. Summary of the Invention

[0003] This invention provides a method for in-situ application of confining pressure for anchoring surrounding rock, which solves the problem in the prior art that it is difficult to apply tangential confining pressure to shallow surrounding rock from an open surface.

[0004] This invention provides a method for in-situ application of confining pressure for anchoring surrounding rock, comprising:

[0005] Anchors are installed in the area to be supported, which is the roof or sidewall of the roadway.

[0006] Water-filled expansion units are installed in sparse areas of the area to be supported. The sparse areas are determined based on the number of anchors installed per unit area in the area to be supported.

[0007] Water is supplied to the water-filled expander and pressurized so that the preload of each of the anchors near the water-filled expander is equal to the target preload.

[0008] According to an embodiment of the present invention, the method for in-situ application of confining pressure for anchoring surrounding rock, wherein the water injection and pressurization of the water-injection expander is performed so that the preload of the anchor near the water-injection expander is equal to the target preload, further includes:

[0009] Monitor the pressure value of the water-filled expander, and if the pressure value is lower than the target pressure value, increase the pressure value so that the pressure value is equal to the target pressure value.

[0010] According to an embodiment of the present invention, a method for in-situ application of confining pressure for anchoring surrounding rock includes a water injection expansion device comprising a water injection pipe, a flexible sleeve, a first hoop ring, and a second hoop ring; one end of the water injection pipe is sealed and connected to the inner wall of the first end of the flexible sleeve through the first hoop ring, and the other end of the water injection pipe is sealed and connected to the inner wall of the second end of the flexible sleeve through the second hoop ring; one end of the water injection pipe having a water inlet passes through the first hoop ring, and a water injection port is provided on the water injection pipe corresponding to the inner wall of the flexible sleeve.

[0011] According to an embodiment of the present invention, the in-situ confining pressure application method for anchoring surrounding rock further includes a one-way connector located at the water inlet.

[0012] According to an embodiment of the present invention, the method for in-situ application of confining pressure for anchoring surrounding rock, wherein the water supply and pressurization to the water injection expander includes:

[0013] Water is supplied and pressurized to the water-injection expander via a water supply assembly;

[0014] The water supply assembly includes a water tank, a water pump, and a water pipe connected in sequence, with the water pipe connected to the one-way connector.

[0015] According to an embodiment of the present invention, the in-situ confining pressure application method for anchoring surrounding rock further includes a pressure gauge for obtaining the pressure value inside the flexible sleeve.

[0016] According to an embodiment of the present invention, the method for in-situ application of confining pressure for anchoring surrounding rock, wherein the water injection and pressurization of the water-injection expander is performed so that the preload of the anchor near the water-injection expander is equal to the target preload, further includes:

[0017] When the preload of the anchor near the water-filled expander is equal to the target preload, the pressure value of the pressure gauge is recorded.

[0018] According to an embodiment of the present invention, the method for in-situ application of confining pressure for anchoring surrounding rock, after recording the pressure value of the pressure gauge, further includes:

[0019] Another water-filled expander is installed in the sparse area, and water is supplied and pressurized to the other water-filled expander so that the two pressure values ​​of the two pressure gauges corresponding to the two water-filled expanders are the same.

[0020] According to an embodiment of the present invention, the method for in-situ application of confining pressure for anchoring surrounding rock, prior to the installation of water-injected expansion devices in the sparse areas of the area to be supported, further includes:

[0021] Drill holes in the sparse area, wherein the diameter of the drill hole is larger than the diameter of the water injection expander, and the length of the drill hole is the same as the length of the installation hole;

[0022] The drilled hole is used to install the water-injection expander, and the mounting hole is used to install the anchor.

[0023] According to an embodiment of the present invention, the method for in-situ application of confining pressure for anchoring surrounding rock, wherein the water-injection expansion device is installed in the sparse area of ​​the area to be supported, includes:

[0024] The water-filled expander is pushed into the borehole using the mounting rod.

[0025] The present invention provides a method for in-situ application of confining pressure for anchoring surrounding rock. To improve the anchor support effect in shallow surrounding rock, water-injected expansion devices are installed in sparse areas of the area to be supported. Water is supplied to and pressurized to the expansion devices, enabling in-situ indirect application of tangential confining pressure to the shallow surrounding rock. This method also compensates for increased anchor preload, promotes the formation of a stable anchoring structure, and improves the anchor support effect. The in-situ application method for confining pressure for anchoring surrounding rock provided by this invention can serve as a novel roadway support technology and method, and can be widely applied in coal mine roadway support engineering. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a flowchart of the in-situ confining pressure application method for anchoring surrounding rock provided by the present invention;

[0028] Figure 2 This is a schematic diagram of the assembly of the water supply component and the water injection expander provided by the present invention;

[0029] Figure 3 This is a schematic diagram of the layout of the water-injection expander provided by the present invention.

[0030] Figure label:

[0031] 1. Water-injected expansion device; 11. Flexible sleeve; 12. Water injection pipe; 121. Water injection port; 13. First hoop; 14. Second hoop; 15. Pressure gauge; 16. One-way connector; 17. Water tank; 18. Manual hydraulic pump; 19. Water delivery pipe; 20. Anchor bolt; 21. Anchor cable; 22. Tunnel cross-section; 23. Tunnel roof. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this embodiment clearer, the technical solutions of this embodiment will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this embodiment, not all embodiments. Based on the embodiments of this embodiment, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this embodiment.

[0033] The water-filled expander 1 involved in the embodiments of the present invention will be described in detail below. Figure 2 As shown, the water-injection expander 1 includes a water injection pipe 12, a flexible sleeve 11, a first hoop 13, and a second hoop 14.

[0034] The flexible sleeve 11 can be made of rubber material. In other words, the flexible sleeve 11 has the ability to expand and contract and can withstand a certain amount of pressure.

[0035] One end of the water injection pipe 12 is sealed to the inner wall of the first end of the flexible sleeve 11 via the first hoop 13. In other words, the first hoop 13 is sleeved on one end of the water injection pipe 12, and the inner side of the first hoop 13 is sealed to the outer side of one end of the water injection pipe 12, and the outer side of the first hoop 13 is sealed to the inner wall of the first end of the flexible sleeve 11.

[0036] Similarly, the other end of the water injection pipe 12 is sealed to the inner wall of the second end of the flexible sleeve 11 via the second hoop 14. In other words, the second hoop 14 is sleeved on the other end of the water injection pipe 12, and the inner side of the second hoop 14 is sealed to the outer side of the other end of the water injection pipe 12, and the outer side of the second hoop 14 is sealed to the inner wall of the second end of the flexible sleeve 11.

[0037] Of course, one end of the water injection pipe 12 with a water inlet is inserted through the first hoop 13, and a water injection port 121 is provided on the water injection pipe 12 corresponding to the inner wall of the flexible sleeve 11.

[0038] It should be noted that, in order to facilitate connection with the water supply component, the water inlet is located outside the flexible sleeve 11. In addition, in order to facilitate the water supply component to deliver water to the flexible sleeve 11 through the water injection pipe 12, the water injection pipe 12 is provided with a water injection port 121. For example, multiple water injection ports 121 are provided on the water injection pipe 12 along its length direction. The water injection ports 121 can be circular.

[0039] It is understandable that the water supply component first supplies water into the water injection pipe 12, and the water in the water injection pipe 12 enters the flexible sleeve 11 through the water injection port 121. When the water in the flexible sleeve 11 is stored to a certain amount, the flexible sleeve 11 will expand. By controlling the water supply of the water supply component, the degree of expansion of the flexible sleeve 11 can be indirectly controlled.

[0040] In addition, such as Figure 1 As shown, in order to facilitate the connection between the water supply component and the water inlet, the water expansion unit 1 also includes a one-way connector 16, which is located at the water inlet.

[0041] In addition, the water supply assembly includes a water tank 17, a water pump and a water pipe 19 connected in sequence, with the water pipe 19 connected to a one-way connector 16.

[0042] Specifically, the water supply pipe 19 and the one-way connector 16 are quickly connected, and the water pump can deliver water from the water tank 17 to the water injection pipe 12 through the water supply pipe 19. For ease of operation, the water pump can be a manual hydraulic pump 18. Additionally, the water tank 17 is connected to the water pump via a water pipe.

[0043] It is particularly important to note that the length of the water-injected expander 1 is slightly shorter than the length of the anchor bolt, and the flexible sleeve 11 has a large expansion capacity after water injection and pressure. A borehole is drilled within the anchoring rock, and the water-injected expander 1 is installed. Water injection and pressure application cause the expander 1 to compress the surrounding rock, thus applying pressure to the surrounding rock inside the anchoring rock. This is equivalent to indirectly applying confining pressure, and the surrounding rock can only deform along the axial direction of the anchor bolt towards the freeway, thereby increasing the preload of the anchor bolt.

[0044] like Figure 1 As shown, the in-situ confining pressure application method for anchoring surrounding rock according to an embodiment of the present invention includes:

[0045] S100, anchors are installed in the area to be supported, which is the roof or sidewall of the roadway.

[0046] Among them, such as Figure 3 As shown, the tunnel cross-section 22 can be rectangular. Anchors are arranged above the tunnel roof 23, including anchor bolts 20 and anchor cables 21. That is, anchors are arranged sequentially above the tunnel roof 23 along the tunnel axial direction.

[0047] S200, water-filled expansion units 1 are installed in the sparse areas of the area to be supported. The sparse areas are determined according to the number of anchors installed per unit area in the area to be supported.

[0048] For example, when dividing the support area into grids, if the number of anchors per unit area is less than or equal to 20, then this area is defined as a sparse area.

[0049] S300, water is supplied to the water-filled expander 1 and pressurized so that the preload of each anchor near the water-filled expander 1 is equal to the target preload.

[0050] In this embodiment of the invention, to improve the anchor bolt support effect in shallow surrounding rock, water-injected expansion devices 1 are installed in sparse areas of the area to be supported. Water is supplied to and pressurized into the expansion devices 1, enabling in-situ indirect application of tangential confining pressure to the shallow surrounding rock. This also compensates for increased anchor bolt preload, promotes the formation of a stable anchoring structure, and improves the anchor bolt support effect. The in-situ confining pressure application method for anchoring surrounding rock in this embodiment of the invention can serve as a novel roadway support technology and method, and can be widely applied in coal mine roadway support engineering.

[0051] Furthermore, in practical applications, water is supplied to the water-filled expander 1 and pressurized so that the preload of the anchor near the water-filled expander 1 is equal to the target preload. This process also includes:

[0052] Monitor the pressure value of the water injection expander 1. If the pressure value is lower than the target pressure value, increase the pressure value to make the pressure value equal to the target pressure value.

[0053] It should be noted that by monitoring the pressure value of the water injection expander 1 in real time and replenishing the pressure of the water injection expander 1 in a timely manner, the support effect can be improved.

[0054] In an optional embodiment, pressurizing the water supply to the water-filled expander 1 includes:

[0055] Water is supplied and pressurized to the water-filled expander 1 via the water supply assembly.

[0056] It should be noted that, based on the difference between the pressure value and the target pressure value, the water supply component is controlled to pressurize the water supply to the water expansion unit 1 until the pressure value equals the target pressure value.

[0057] For example, water is supplied to the water-filled expander 1 and pressurized by reciprocating the lever of the manual hydraulic pump 18.

[0058] In an optional embodiment, the water-filled expander 1 further includes a pressure gauge 15 for obtaining the pressure value inside the flexible sleeve 11.

[0059] For example, the measuring end of the pressure gauge 15 extends into the interior of the flexible sleeve 11, thereby obtaining the pressure value inside the flexible sleeve 11 in real time.

[0060] In an optional embodiment, water is supplied to and pressurized to the water-filled expander 1 so that the preload of the anchor near the water-filled expander 1 is equal to the target preload, and then the process further includes:

[0061] When the preload of the anchor near the water-filled expander 1 is equal to the target preload, record the pressure value of the pressure gauge 15.

[0062] In other words, the pressure value inside the flexible sleeve 11 can be determined in real time through the pressure gauge 15.

[0063] In an optional embodiment, the pressure value of pressure gauge 15 is recorded, followed by:

[0064] Install another water-filled expander 1 in the sparse area, and pressurize the other water-filled expander 1 so that the two pressure values ​​of the two pressure gauges 15 corresponding to the two water-filled expanders 1 are the same.

[0065] Among them, the two water-filled expanders 1 located in the same sparse region need to be spaced a certain distance apart.

[0066] It should be noted that by comparing the two pressure values ​​corresponding to the two pressure gauges 15, multiple water-filled expanders 1 can be installed conveniently and quickly.

[0067] In an optional embodiment, the water-filled expansion tank 1 is installed in the sparse area of ​​the area to be supported, and the process further includes:

[0068] Drill holes in sparse areas, with the hole diameter being larger than the diameter of the water-injection expander 1, and the hole length being the same as the installation hole length.

[0069] The drilled holes are used to install the water-injection expander 1, and the mounting holes are used to install the anchors.

[0070] It should be noted that, compared to the arrangement of anchor bolts 20, anchor cables 21 are usually sparsely arranged. Therefore, it is possible to set up holes at the arrangement of anchor cables 21, for example, to set up a water-filled expansion device 1 between two adjacent anchor cables 21.

[0071] In an optional embodiment, a water-filled expansion tank 1 is installed in a sparse area of ​​the area to be supported, including:

[0072] Use the mounting rod to push the water-filled expander 1 into the borehole.

[0073] It should be noted that the water expansion unit 1 is pushed into the borehole using the installation rod until the appropriate depth is reached. At this point, the one-way connector 16 of the water expansion unit 1 is exposed in the borehole.

[0074] For ease of understanding, the following is a general description of the in-situ application method of confining pressure for anchoring surrounding rock in an embodiment of the present invention (taking the roadway roof 23 as an example).

[0075] Anchor bolts 20, anchor cables 21, steel strips and anchor mesh are installed in the area to be supported;

[0076] Drill holes in sparse areas, with the hole diameter being larger than the diameter of the water-injection expander 1, and the hole length being the same as the installation hole length.

[0077] Use the mounting rod to push the water-filled expansion unit 1 into the borehole until the appropriate depth is reached. At this point, the one-way connector 16 of the water-filled expansion unit 1 is exposed in the borehole.

[0078] Water pipe 19 is connected to one-way connector 16;

[0079] By repeatedly pressing the lever of the manual hydraulic pump 18, water is supplied to the water-filled expander 1 and pressurized until the preload of each anchor near the water-filled expander 1 is equal to the target preload; when the preload of the anchor near the water-filled expander 1 is equal to the target preload, the pressure value of the pressure gauge 15 is recorded.

[0080] Install another water-filled expansion unit 1 in the sparse area, and pressurize the other water-filled expansion unit 1 by supplying water so that the two pressure values ​​of the two pressure gauges 15 corresponding to the two water-filled expansion units 1 are the same.

[0081] Repeat the previous step to complete the installation of multiple water-injection expansion units 1 on the roof slab 23 of the entire tunnel;

[0082] Monitor the pressure value of each water-filled expander 1. If the pressure value is lower than the target pressure value, increase the pressure value to make the pressure value equal to the target pressure value.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this embodiment, and not to limit them; although this embodiment has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this embodiment.

Claims

1. A method for in-situ application of confining pressure for anchoring surrounding rock, characterized in that, include: Anchors are installed in the area to be supported, which is the roof or sidewall of the roadway. Water-filled expansion units are installed in sparse areas of the area to be supported. The sparse areas are determined based on the number of anchors installed per unit area in the area to be supported. Water is supplied and pressurized to the water-injection expander, and the expansion of the water-injection expander applies a squeezing force to the surrounding rock, thereby achieving in-situ indirect application of tangential confining pressure to the shallow surrounding rock, and compensating for and increasing the preload of each anchor near the water-injection expander until the preload equals the target preload.

2. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 1, characterized in that, The process of pressurizing water supply to the water-filled expander to make the preload of the anchor near the water-filled expander equal to the target preload further includes: Monitor the pressure value of the water-filled expander, and if the pressure value is lower than the target pressure value, increase the pressure value so that the pressure value is equal to the target pressure value.

3. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 1 or 2, characterized in that, The water-injection expander includes a water injection pipe, a flexible sleeve, a first hoop ring, and a second hoop ring. One end of the water injection pipe is sealed to the inner wall of the first end of the flexible sleeve through the first hoop ring, and the other end of the water injection pipe is sealed to the inner wall of the second end of the flexible sleeve through the second hoop ring. One end of the water injection pipe with a water inlet passes through the first hoop ring, and a water injection port is provided on the water injection pipe corresponding to the inner wall of the flexible sleeve.

4. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 3, characterized in that, The water-injection expander also includes a one-way connector, which is located at the water inlet.

5. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 4, characterized in that, The pressurization of water supply to the water-filled expander includes: Water is supplied and pressurized to the water-injection expander via a water supply assembly; The water supply assembly includes a water tank, a water pump, and a water pipe connected in sequence, with the water pipe connected to the one-way connector.

6. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 3, characterized in that, The water-injection expander also includes a pressure gauge, which is used to obtain the pressure value inside the flexible sleeve.

7. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 6, characterized in that, The process of pressurizing water supply to the water-filled expander to make the preload of the anchor near the water-filled expander equal to the target preload further includes: When the preload of the anchor near the water-filled expander is equal to the target preload, the pressure value of the pressure gauge is recorded.

8. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 7, characterized in that, The process of recording the pressure value of the pressure gauge further includes: Another water-filled expander is installed in the sparse area, and water is supplied and pressurized to the other water-filled expander so that the two pressure values ​​of the two pressure gauges corresponding to the two water-filled expanders are the same.

9. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 1, characterized in that, Before installing water-injected expansion units in the sparse areas of the area to be supported, the following steps are also included: Drill holes in the sparse area, wherein the diameter of the drill hole is larger than the diameter of the water injection expander, and the length of the drill hole is the same as the length of the installation hole; The drilled hole is used to install the water-injection expander, and the mounting hole is used to install the anchor.

10. The method for in-situ application of confining pressure for anchoring surrounding rock according to claim 9, characterized in that, The installation of water-filled expansion tanks in the sparse areas of the area to be supported includes: The water-filled expander is pushed into the borehole using the mounting rod.

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