Grouting-layer-free deep-hole high-pressure grouting system for roadway bottom plate

Abstract

The invention relates to the technical field of coal mine roadway supporting, in particular to a roadway bottom plate grout-stopping-layer-free deep hole high-pressure grouting system which comprises a grouting pump, a grouting pressure monitoring system is fixedly installed at the output end of a mixer, and a seamless grouting pipe is fixedly installed at one end of the grouting pressure monitoring system. A grout fixing section, a hole sealing and grout stopping section and a grout outlet section are sequentially arranged on the portion, penetrating into the roadway bottom plate surrounding rock, of the seamless grouting pipe from top to bottom, and a composite material hole sealing agent is arranged in the grout fixing section. According to the grouting-layer-free deep hole high-pressure grouting system for the roadway bottom plate, a seamless grouting pipe is arranged in a deep hole, and a lengthened pipe fixing section is arranged, so that grout seeps out of surrounding rock with good deep integrity, and it can be guaranteed that the diffusion and seepage path of the grout under high grouting pressure in the initial stage and high pressure of the deep hole under the grouting-layer-free condition; the grout in the grout outlet section firstly expands in the horizontal direction and then expands along cracks, the deeper the hole is, the larger the overall diffusion radius is, and the stability of the bottom plate is improved.

Description

Technical Field

[0001] The invention relates to the technical field of coal mine tunnel support, in particular to a tunnel bottom plate non-stop grouting layer deep hole high pressure grouting system. Background Art

[0002] With the increase of coal mining depth, the contradiction between the low strength of coal-bearing soft rock and high ground stress has become increasingly prominent, resulting in serious deformation of the tunnel floor, affecting mine transportation and production safety. After the coal mine tunnel is excavated, the floor is usually supported later than the side and roof due to the influence of gangue loading. Some tunnel floors are more weakly supported than unsupported, resulting in the floor rock being broken and waterlogged after the floor is deformed. Therefore, the main technical method for controlling floor heave is to reinforce the floor with support and grouting.

[0003] The goal of grouting the bottom plate of a coal mine roadway is to fill the weak surfaces and cracks of the bottom plate surrounding rock with slurry and cement the bottom plate rock mass to improve the integrity and strength of the bottom plate surrounding rock, and at the same time play a role in blocking the fissure water. To achieve the above grouting effect, the grouting material must have high strength, short consolidation time, and wide diffusion range. Generally, the highest possible grouting pressure should be used. High-pressure grouting should be used to treat the bottom bulge of the roadway. One of the key technologies is to seal the hole and fix the pipe. Since the broken bottom plate does not have a reliable grouting layer, the length of the fixing pipe is short, and the pressure bearing capacity is small; the sealing depth is shallow, and the slurry diffusion range is limited; the sealing consolidation time is long, which affects the construction period of the entire grouting process.

[0004] The existing grouting and sealing technologies at home and abroad mainly include cement-water glass and cotton yarn winding to seal the hole and fix the pipe, cement bags or films filled with polymer materials to expand the hole and fix the pipe, and inflatable capsule tube sealing. For example, Chinese patents CN115749675A, CN220225253U, CN114251073A, etc. all use bags or outer elastic films to seal the holes by grouting and expansion. Chinese patent CN115450219A discloses a method for sealing the rock hole wall by mechanical extrusion and expansion of a spinning component. Patents CN112267848A, CN220267662U, CN220849627U, etc. mainly use inflation to expand the volume of air bags or rubber hoses to achieve sealing. The above patents all provide effective technical approaches in specific application scenarios. The sealing methods such as mechanical expansion, inflatable airbags and grouting expansion bags are complex in design and are mostly used for sealing holes in the side and roof with larger apertures. The sealing length is limited and it is not resistant to high pressure. In terms of sealing technology for high-pressure grouting, patent CN114278251A discloses a method for sealing and plugging pressure in surrounding rock fissures in coal mine tunnels. The method comprises a first non-pressure sealing, a second "two plugging and one injection" pressure sealing, and multiple sealings to achieve the technical indicators of high-pressure sealing. Non-pressure sealing includes mechanical sealing, cement slurry sealing and polymer foam material sealing. The "two plugging and one injection" sealing is carried out by grouting between the "two plugging" or the bag, and the pressure grouting is used to achieve the function of slurry plugging the fissures and actively supporting the drilling. This method requires a number of complex processes such as grouting bags and through-holes in pipes, which is difficult to promote and apply in the treatment of tunnel floor heave.

[0005] In order to solve the above problems, we have made improvements and proposed a deep hole high-pressure grouting system for the tunnel floor without a slurry layer. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] The present invention provides a deep hole high-pressure grouting system for a tunnel floor without a grouting stop layer, comprising a grouting pump, wherein the input end of the grouting pump is provided with a slurry barrel, the output end of the grouting pump is connected with a mixer via a slurry outlet pipe, a grouting pressure monitoring system is fixedly installed at the output end of the mixer, a seamless grouting pipe is fixedly installed at one end of the grouting pressure monitoring system, and the seamless grouting pipe penetrates into the surrounding rock of the tunnel floor, and the portion of the seamless grouting pipe that penetrates into the surrounding rock of the tunnel floor is sequentially provided with a solid grouting section, a hole sealing and stopping grouting section and a slurry outlet section from top to bottom, and a composite material sealing agent is arranged inside the solid grouting section.

[0008] As a preferred technical solution of the present invention, the sealing and grouting section includes a coarse sand layer and a wedge-shaped mesh. The coarse sand layer is arranged at the bottom end of the composite material sealer. The assembly sequence is to first fix the wedge-shaped mesh to the lower end of the seamless grouting pipe with a wire tie, and then lay the coarse sand layer.

[0009] As a preferred technical solution of the present invention, the composite material sealing agent includes polyurethane and water glass, and the mixed properties of organic materials and inorganic materials are adjusted by adding a specific catalyst.

[0010] As a preferred technical solution of the present invention, the composite material sealant is packaged in a composite material sealant packaging bag, the composite material sealant packaging bag includes a first material area and a second material area, and a partition layer is arranged between the first material area and the second material area, a first material injection hole is arranged at the top of the first material area, a second material injection hole is arranged at the top of the second material area, a mixing outlet is arranged at the bottom of the composite material sealant packaging bag, an opening valve is arranged at the bottom of the mixing outlet, and a sealing edge is arranged at the top of the composite material sealant packaging bag.

[0011] As a preferred technical solution of the present invention, a valve is provided on the slurry outlet pipe, and a check valve is provided on the top of the seamless grouting pipe.

[0012] As a preferred technical solution of the present invention, it also includes a cleaning liquid barrel and a waste liquid barrel, and the waste slurry in the pipeline is cleaned by the cleaning liquid in the cleaning liquid barrel and injected into the waste liquid barrel.

[0013] As a preferred technical solution of the present invention, the grouting pressure monitoring system is a three-way connected hydraulic sensor. The hydraulic pressure gauge should adopt a high-precision dynamic monitoring sensor with high-frequency information collection and display output functions. The diffusion characteristics of the slurry can be fed back in real time based on the changes in the grouting pressure.

[0014] As a preferred technical solution of the present invention, two slurry outlet pipes are provided, and the two slurry outlet pipes are connected to a mixer to ensure effective mixing of the double slurries and guarantee the grouting effect.

[0015] The beneficial effects of the present invention are:

[0016] 1. A deep hole high-pressure grouting system for a tunnel floor without a stop grouting layer. The grouting system takes into account the characteristics of the tunnel floor without a stop grouting layer, arranges seamless grouting pipes in deep holes, and sets an extended solid pipe section so that the slurry first seeps out from the deep surrounding rock with good integrity, which can ensure the initial high grouting pressure. The diffusion seepage path of the slurry under the deep hole high pressure is that under the condition of no stop grouting layer, the slurry in the slurry outlet section first expands mainly in the horizontal direction, and then expands along the cracks. The deeper the hole, the larger the overall diffusion radius, thereby improving the stability of the floor.

[0017] 2. A deep-hole high-pressure grouting system without a stopper layer on the bottom plate of a tunnel. The composite material sealing agent used in the grouting system is simple and easy to carry, can quickly fix the pipe, has good fluidity, does not foam, is self-compacting, and meets the requirements of high strength and high toughness after curing.

[0018] 3. A deep hole high-pressure grouting system for the tunnel floor without a stop grouting layer. The grouting system is equipped with a dynamic monitoring system for grouting pressure and a mixer. Based on the real-time grouting pressure changes, grouting volume, and surface grouting conditions, combined with the basic principles of fluid mechanics, it can scientifically determine the timing of grouting completion and ensure the grouting effect.

[0019] 4. A deep hole high pressure grouting system without a stopper layer for the tunnel floor. The seamless grouting pipe of the grouting system can be applied to boreholes of different diameters, thus reducing the difficulty of drilling construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 It is a structural schematic diagram of a deep hole high pressure grouting system for a roadway floor without a stop grout layer according to the present invention;

[0022] Figure 2 It is a diagram of a deep hole high pressure grouting system for a roadway floor without a stop grouting layer according to the present invention;

[0023] Figure 3 It is a schematic diagram of slurry diffusion of a deep hole high pressure grouting system without a stop slurry layer in a tunnel floor of the present invention;

[0024] In the figure: 1. slurry barrel; 2. grouting pump; 3. valve; 4. slurry outlet pipe; 5. mixer; 6. grouting pressure monitoring system; 7. seamless grouting pipe; 8. check valve; 9. slurry solidification section; 10. composite material sealer; 11. sealing and slurry stopping section; 1101. coarse sand layer; 1102. wedge-shaped net; 12. cleaning liquid barrel; 13. waste liquid barrel; 14. composite material sealer packaging bag; 1401. first material area; 1402. second material area; 1403. first material injection hole; 1404. second material injection hole; 1405. sealing edge; 1406. partition layer; 1407. mixed material outlet; 1408. opening valve. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0026] Example: Figure 1 - Figure 3As shown, a deep hole high-pressure grouting system for a tunnel floor without a grouting layer comprises a grouting pump 2, the input end of the grouting pump 2 is provided with a slurry barrel 1, the output end of the grouting pump 2 is connected to a mixer 5 through a slurry outlet pipe 4, a grouting pressure monitoring system 6 is fixedly installed on the output end of the mixer 5, a seamless grouting pipe 7 is fixedly installed on one end of the grouting pressure monitoring system 6, and the seamless grouting pipe 7 penetrates deep into the surrounding rock of the tunnel floor, and the part of the seamless grouting pipe 7 penetrating into the surrounding rock of the tunnel floor is provided with a solid grouting section 9, a hole sealing and stopping grouting section 11 and a slurry outlet section from top to bottom, a composite material sealing agent 10 is provided inside the solid grouting section 9, a valve 3 is provided on the slurry outlet pipe 4, and a check valve 8 is provided on the top of the seamless grouting pipe 7.

[0027] Specifically, refer to Figure 1 The sealing and grouting section 11 includes a coarse sand layer 1101 and a wedge-shaped net 1102. The coarse sand layer 1101 is arranged at the bottom end of the composite material sealer 10. The assembly sequence is to first fix the wedge-shaped net 1102 to the lower end of the seamless grouting pipe 7 with a wire tie, and then lay the coarse sand layer 1101.

[0028] Preferably, the composite material sealer 10 includes polyurethane and water glass, and by adding a specific catalyst and blending the mixed properties of organic materials and inorganic materials, the sealing performance of the composite material 10 meets the requirements of good fluidity, no foaming, self-compacting, rapid curing within 5 to 10 minutes, high strength and high toughness after curing.

[0029] Specifically, refer to Figure 2 The composite material sealant 10 is packaged in a composite material sealant packaging bag 14, which includes a first material area 1401 and a second material area 1402, and a partition layer 1406 is provided between the first material area 1401 and the second material area 1402, a first material injection hole 1403 is provided at the top of the first material area 1401, a second material injection hole 1404 is provided at the top of the second material area 1402, and a mixed material outlet 1407 is provided at the bottom of the composite material sealant packaging bag 14, An opening valve 1408 is provided at the bottom of the mixing outlet 1407, a sealing edge 1405 is provided at the top of the composite material sealer packaging bag 14, and the inside of the mixing outlet 1407 is filled with a wedge-shaped net, which can expand radially along the outlet instantly after the opening valve 1408 is pulled out to fill the gap of the opening valve 1408. The design of the wedge-shaped net fully considers the principles of fluid dynamics, and minimizes the resistance of the fluid passing through to the greatest extent by optimizing the shape and arrangement of the mesh holes, while ensuring the effective mixing of the two slurries.

[0030] Specifically, refer to Figure 1 , and also includes a cleaning liquid barrel 12 and a waste liquid barrel 13. The waste slurry in the pipeline is cleaned by the cleaning liquid in the cleaning liquid barrel 12 and injected into the waste liquid barrel 13.

[0031] Preferably, the grouting pressure monitoring system 6 is a three-way connected hydraulic sensor. The hydraulic pressure gauge should adopt a high-precision dynamic monitoring sensor with high-frequency information collection and display output functions. The grouting pressure changes can provide real-time feedback on the diffusion characteristics of the slurry.

[0032] Specifically, refer to Figure 1 There are two slurry outlet pipes 4, and the two slurry outlet pipes 4 are connected to the mixer 5 to ensure the effective mixing of the double slurries and the grouting effect.

[0033] Working steps: S1, drilling a deep hole in the tunnel floor, using an extended seamless grouting pipe 7 to penetrate into the bottom of the hole, and forming a bottom hole sealing and grouting section 11 through a wedge-shaped net 1102 and a coarse sand layer 1101, so that the grouting section is controlled in the range of 0.5 to 1m;

[0034] S2, open the opening valve 1408 of the composite material sealing agent 10, squeeze the composite material sealing agent 10 into the gap between the seamless grouting pipe 7 and the bottom plate surrounding rock, the composite material sealing agent 10 is a viscous time-varying slurry, and after penetrating into the coarse sand layer 1101 and the wedge-shaped net 1102, a stable sealing and grouting section 11 is formed;

[0035] S3, after the composite material sealing agent 10 is cured, a long-distance, high-strength solid slurry section 9 is formed, which significantly improves the pressure resistance performance compared with the conventional sealing method, and the pipe solidification time can be controlled within 3 to 5 minutes;

[0036] S4, after the pipe is fixed, connect the grouting pressure monitoring system 6, the mixer 5, and the grouting pump 2;

[0037] S5. Before grouting, clear the pipeline with cleaning fluid and apply pressure to open the surrounding rock cracks;

[0038] S6, formal grouting, based on the monitored grouting pressure changes, combined with the grouting volume and surface grouting conditions, comprehensively determine the time to end the grouting;

[0039] S7, after the grouting is completed, close the check valve 8 of the seamless grouting pipe 7 and disconnect the connection with the seamless grouting pipe 7;

[0040] S8, clean the waste slurry in the pipeline with cleaning liquid and inject it into the waste liquid barrel 13.

[0041] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A deep hole high pressure grouting system for a tunnel floor without a grouting layer, comprising a grouting pump (2), characterized in that: The input end of the grouting pump (2) is provided with a slurry barrel (1), the output end of the grouting pump (2) is connected to a mixer (5) via a slurry outlet pipe (4), the output end of the mixer (5) is fixedly installed with a grouting pressure monitoring system (6), one end of the grouting pressure monitoring system (6) is fixedly installed with a seamless grouting pipe (7), and the seamless grouting pipe (7) penetrates into the surrounding rock of the tunnel floor, and the part of the seamless grouting pipe (7) that penetrates into the surrounding rock of the tunnel floor is sequentially provided with a slurry solidification section (9), a hole sealing and slurry stopping section (11) and a slurry outlet section from top to bottom, and a composite material sealing agent (10) is provided inside the slurry solidification section (9).

2. A tunnel floor deep hole high pressure grouting system without a grouting layer according to claim 1, characterized in that: The hole sealing and grouting stopping section (11) comprises a coarse sand layer (1101) and a wedge-shaped net (1102), wherein the coarse sand layer (1101) is arranged at the bottom end of the composite hole sealing agent (10), and the assembly sequence thereof is to first fix the wedge-shaped net (1102) to the lower end of the seamless grouting pipe (7) by using a tying wire, and then lay the coarse sand layer (1101).

3. The deep hole high pressure grouting system for tunnel floor without grouting layer according to claim 1 is characterized in that: The composite material sealing agent (10) comprises polyurethane and water glass, and a specific catalyst is added to adjust the mixed properties of organic materials and inorganic materials.

4. A tunnel floor deep hole high pressure grouting system without a grouting layer according to claim 3, characterized in that: The composite material sealant (10) is packaged in a composite material sealant packaging bag (14), the composite material sealant packaging bag (14) comprising a first material area (1401) and a second material area (1402), a partition layer (1406) being provided between the first material area (1401) and the second material area (1402), a first material injection hole (1403) being provided at the top of the first material area (1401), a second material injection hole (1404) being provided at the top of the second material area (1402), a mixed material outlet (1407) being provided at the bottom of the composite material sealant packaging bag (14), an opening valve (1408) being provided at the bottom of the mixed material outlet (1407), and a sealing edge (1405) being provided at the top of the composite material sealant packaging bag (14).

5. The deep hole high pressure grouting system for tunnel floor without grouting layer according to claim 1 is characterized in that: The slurry outlet pipe (4) is provided with a valve (3), and the top of the seamless grouting pipe (7) is provided with a check valve (8).

6. The deep hole high pressure grouting system for tunnel floor without grouting layer according to claim 1 is characterized in that: It also comprises a cleaning liquid barrel (12) and a waste liquid barrel (13), and the waste slurry in the pipeline is cleaned by the cleaning liquid in the cleaning liquid barrel (12) and injected into the waste liquid barrel (13).

7. The deep hole high pressure grouting system for tunnel floor without grouting layer according to claim 1 is characterized in that: The grouting pressure monitoring system (6) is a three-way connected hydraulic sensor. The hydraulic pressure gauge should adopt a high-precision dynamic monitoring sensor with high-frequency information collection and display output functions. The grouting pressure change can provide real-time feedback on the diffusion characteristics of the slurry.

8. The deep hole high pressure grouting system for tunnel floor without grouting layer according to claim 1 is characterized in that: The slurry outlet pipes (4) are provided with two, and the two slurry outlet pipes (4) are connected to the mixer (5) to ensure effective mixing of the double slurries and guarantee the grouting effect.

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