Drilling freezing-grouting-supporting integrated treatment method for yellow mud roadway roof

Abstract

The invention discloses a yellow mud roadway roof drilling freezing-grouting-supporting integrated treatment method, and relates to the technical field of roadway treatment. The method comprises the steps that a yellow mud layer is layered; drilling upwards to a yellow mud layer, and then drilling in a horizontal branch manner; branch drilling is adopted in the horizontal drilling process, liquid nitrogen is injected to freeze the yellow mud, and circulation is repeated till the lower layer of the yellow mud area is completely frozen; then directly injecting slurry for solidification; and then the branches are tunneled to other layers of the yellow mud, the same operation is repeated for solidification, and the anchor cables are installed after stabilization. By means of the treatment method, effective treatment and supporting of the yellow mud area are achieved, and safety and stability of the roadway are guaranteed. Through the method, the problems of seepage, sinking and the like of the yellow mud roof are effectively solved, the strength and stability of the roof are enhanced, construction risks are reduced, and personnel safety is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of roadway treatment, and in particular to an integrated treatment method for freezing-grouting-supporting of the roof of a loess roadway by drilling holes. Background Art

[0002] In mining engineering, the treatment of the roof of a loess roadway has always been a difficult problem. At present, the traditional treatment methods often have limited effects when facing complex geological conditions. For example, when using traditional methods such as shotcreting, timbering, and grouting reinforcement with cable bolting and wire mesh to treat the roof caving area of a loess roadway, since the roof is covered by loose and easily flowing loess, these methods cannot effectively control the continuous caving of the loess, which affects the removal of the loess in the roadway and the repair of the roof.

[0003] The roof of a loess roadway is prone to roof fall, which has a serious impact on underground production and even causes casualties. At the same time, the roof of a loess roadway is also prone to slime problems. Therefore, there are many problems in the current treatment of the roof of a loess roadway, and there is an urgent need for a more effective treatment method to deal with complex geological conditions and ensure the safety of the roadway. Summary of the Invention

[0004] The purpose of the present invention is to provide an integrated treatment method for freezing-grouting-supporting of the roof of a loess roadway by drilling holes to solve the above technical problems existing in the prior art.

[0005] To achieve the above purpose, the present invention provides the following solution: An integrated treatment method for freezing-grouting-supporting of the roof of a loess roadway by drilling holes, comprising the following steps:

[0006] S1. Divide the loess layer into multiple layers according to the thickness of the loess layer and treat each layer layer by layer;

[0007] S2. Open a main road in the roadway by drilling upward. After the main road drills to the loess layer, carry out horizontal drilling, and use a drill pipe to drill a horizontal branch by means of branch drilling;

[0008] S3. Inject liquid nitrogen into the loess layer through the horizontal branch to achieve temporary freezing;

[0009] S4. After the loess around the previous horizontal branch is frozen, repeat steps S2-S3 to complete the drilling, nitrogen injection, and consolidation of the next horizontal branch; repeat the cycle to complete the drilling, nitrogen injection, and consolidation of multiple horizontal branches until the lower layer of the loess area is completely frozen;

[0010] S5. Inject slurry into the frozen horizontal branch to cause the loess to react with the slurry to achieve consolidation;

[0011] S6. After the yellow mud layer at this level is consolidated, repeat steps S1 - S5 to complete the directional drilling, liquid nitrogen freezing, and grouting reinforcement of the yellow mud layer at the next level.

[0012] S7. After the yellow mud layer is stabilized by grouting reinforcement and forms an overall load-bearing structure, install anchor cables, and successively complete drilling, installing anchor cables, and tensioning and locking.

[0013] In some alternative implementation manners of the above treatment method, the included angle between the main road and the horizontal is 30° - 60°.

[0014] In some alternative implementation manners of the above treatment method, the arrangement of multiple said horizontal branches presents a harpoon shape.

[0015] In some alternative implementation manners of the above treatment method, during the drilling process, a casing is used as the drill pipe. The drill pipe includes an outer pipe body and an inner pipe body that are sleeved with each other. A number of outer pipe holes with a diameter of 5 cm are opened on the outer pipe body, and the distance between adjacent two outer pipe holes is 20 - 30 cm.

[0016] In some alternative implementation manners of the above treatment method, during the nitrogen injection and grouting process, liquid nitrogen or slurry is injected into the inner pipe body, and then the inner pipe is withdrawn. The liquid nitrogen or slurry is transported to the yellow mud area through the said outer pipe holes.

[0017] In some alternative implementation manners of the above treatment method, in step S3, the nitrogen injection speed is 20 - 30 L / min, the nitrogen injection pressure is 5 - 10 MPa, the nitrogen injection time is 10 - 15 min, and the nitrogen injection range is a radius of 3 - 5 m along the periphery of the drill pipe.

[0018] In some alternative implementation manners of the above treatment method, in step S5, the grouting speed is 20 - 30 L / min, the grouting pressure is 5 - 10 MPa, the grouting time is 10 - 15 min, and the grouting range 9 is a radius of 3 - 5 m along the periphery of the drill pipe.

[0019] In some alternative implementation manners of the above treatment method, the grouting setting time is 50 - 100 min, and the strength after setting reaches 65 - 80 MPa.

[0020] In some alternative implementation manners of the above treatment method, the slurry is a mixed solution of the organic polymer material Marisan.

[0021] In some alternative implementation manners of the above treatment method, according to the range size of the yellow mud area above the coal seam, the entire yellow mud area is treated by means of the cooperation of two roadways or multiple roadways.

[0022] Compared with the prior art, the present invention discloses at least the following technical effects:

[0023] 1. The present invention effectively improves the stability and bearing capacity of the roof of the loess roadway, ensuring the safe use of the roadway. This method can timely treat the roof of the loess roadway, prevent safety accidents such as seepage of the loess roof, and reduce safety risks.

[0024] 2. The simultaneous freezing, grouting and support of the ultra-long directional drilling in the roof of the loess roadway improve the treatment efficiency and shorten the construction period.

[0025] 3. The all-round and in-depth treatment of the roof of the loess roadway is realized, improving the integrity and mechanical properties of the roof and extending the service life of the roadway.

[0026] 4. This integrated treatment method can adapt to the treatment of the roof of the loess roadway under different geological conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 It is a flowchart of the integrated treatment method provided by the embodiment of the present invention;

[0029] Figure 2 It is a schematic diagram of the treatment process of the integrated treatment method provided by the embodiment of the present invention;

[0030] Figure 3 It is a schematic diagram of the borehole layout in the lower loess layer, and a schematic diagram of the tunneling and nitrogen injection of the first horizontal branch in the lower loess layer;

[0031] Figure 4 It is a schematic diagram when the nitrogen injection of the first horizontal branch in the lower loess layer is completed, and at the same time, the second horizontal branch is tunneling and injecting nitrogen;

[0032] Figure 5 It is a schematic diagram when the nitrogen injection of each horizontal branch in the lower loess layer is completed, and the first horizontal branch starts to grout and consolidate;

[0033] Figure 6 It is a schematic diagram after the grouting consolidation of each horizontal branch in the lower loess layer;

[0034] Figure 7 It is a schematic diagram of the borehole layout in the upper loess layer, and a schematic diagram of the borehole layout of the first horizontal branch in the upper loess layer;

[0035] Figure 8 It is a schematic diagram after the complete consolidation of the loess layer;

[0036] Figure 9 Schematic diagram of borehole layout in another roadway under the combined treatment of double roadways;

[0037] Figure 10 Schematic diagram of a structure of a drill pipe in an embodiment of the present invention.

[0038] In the figure: 1, coal seam; 101, roadway one; 102, roadway two; 2, immediate roof; 3, main roof; 4, loess layer; 5, yellow mud layer; 51, lower yellow mud layer; 52, upper yellow mud layer; 6, lower main road; 61, lower horizontal branch; 7, upper main road; 71, upper horizontal branch; 8, nitrogen injection range; 9, grouting range; 11, outer pipe body; 12, inner pipe body; 13, outer pipe holes. Specific embodiments

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0040] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0041] Refer to Figure 1 As shown, there are an immediate roof 2, a main roof 3, a loess layer 4, and a yellow mud layer 5 above the coal seam 1. There is a large - scale yellow mud layer 5 above a certain coal seam 1, and it is necessary to treat this yellow mud layer 5.

[0042] Since the area of the yellow mud region is large, it is not suitable for one - time consolidation. Therefore, in actual treatment, a method of combining two roadways is adopted for operation. Specifically, the treatment work is first carried out in one of the roadways (roadway one 101), and after its completion, the treatment is carried out in the other roadway (roadway two 102). Through such a sequence and mutual cooperation, the comprehensive treatment of the yellow mud region is finally achieved.

[0043] Refer to Figures 1 to 10 As shown, the present invention provides an integrated treatment method for freezing - grouting - supporting of boreholes in the roof of a yellow mud roadway, including the following steps:

[0044] S1. According to the thickness of the yellow mud layer 5, the yellow mud layer 5 is divided into multiple layers; in this embodiment, specifically, the yellow mud layer 5 is divided into upper and lower two layers for step - by - step treatment, that is, the lower yellow mud layer 51 and the upper yellow mud layer 52.

[0045] S2. In roadway 101, the lower main road 6 is opened by drilling upward. The lower main road 6 is set at an angle of 45° with the horizontal plane and reaches the lower yellow mud layer 51. Horizontal drilling is carried out in the lower yellow mud layer 51. During the horizontal drilling process, branch drilling is adopted to drill a lower horizontal branch 61. The lower horizontal branch 61 extends horizontally along the yellow mud layer 5 and reaches the designed position.

[0046] In a specific embodiment, the setting angle of the main road (including the lower main road 6 and the upper main road 7) can be 30° - 60°.

[0047] In a specific embodiment, multiple lower horizontal branches 61 need to be drilled to form a larger coverage area. For example, in this embodiment, 4 lower horizontal branches 61 are designed and arranged by directional drilling, including the first horizontal branch, the second horizontal branch, the third horizontal branch, and the fourth horizontal branch. The distance between adjacent lower horizontal branches 61 is 5 m, and the 4 lower horizontal branches 61 are distributed in a trident shape.

[0048] In a specific embodiment, during the drilling process, a casing is used as the drill pipe. The drill pipe includes an outer pipe body 11 and an inner pipe body 12 that are sleeved with each other. A number of outer pipe holes 13 with a diameter of 5 cm are opened on the outer pipe body 11. The distance between adjacent outer pipe holes 13 is 20 - 30 cm, preferably 30 cm.

[0049] S3. Inject liquid nitrogen into the drill pipe. The liquid nitrogen enters the lower horizontal branch 61 through the drill pipe and then is injected into the yellow mud, freezing the yellow mud, reducing its fluidity and deformability, and achieving temporary consolidation.

[0050] In step S3, liquid nitrogen is injected into the drill pipe through an injection device. When injecting nitrogen, the injection rate is 20 - 30 L / min, the injection pressure is 5 - 10 MPa, the injection time is 10 - 15 min, and the injection range 8 is a radius of 3 - 5 m along the periphery of the drill pipe.

[0051] In a specific embodiment, liquid nitrogen is directly injected into the drill pipe through an injection gun. When injecting nitrogen, the injection rate is 20 L / min, the injection pressure is set at 5 MPa, the injection time is 10 min, and the injection range 8 is a radius of 3 m along the periphery of the drill pipe. Under the action of the injection gun pressure, the liquid nitrogen enters the yellow mud through the outer pipe holes 13.

[0052] S4. After the yellow mud around the previous lower horizontal branch 61 is completely frozen, repeat steps S2 - S3 to complete the drilling, nitrogen injection, and consolidation of the next lower horizontal branch 61. Repeat the cycle to complete the drilling, nitrogen injection, and consolidation of all lower horizontal branches 61 until the lower layer of the yellow mud area is completely frozen.

[0053] S5. After the lower layer 51 of the yellow mud is completely frozen, the mixture of the organic polymer material Marisal (polyimide resin material) is directly injected into each lower horizontal branch 61 through an injection gun. The injected slurry enters the yellow mud area through the holes 13 of the outer pipe under the action of pressure and reacts with the yellow mud to achieve permanent consolidation.

[0054] In step S5, the grouting speed is 20 - 30 L / min, the grouting pressure is 5 - 10 MPa, the grouting time is 10 - 15 min, the grouting range 9 is a radius of 3 - 5 m along the periphery of the drill pipe. The slurry mixture coagulates within 50 - 100 min, and the final strength can reach 65 - 80 MPa.

[0055] In a specific embodiment, the grouting speed is set to 25 L / min, the grouting pressure is set to 10 MPa, the grouting time is 15 min, and the grouting range 9 is a radius of 3 m along the periphery of the lower horizontal branch 61. The final strength of the slurry mixture can reach 72 MPa after coagulation.

[0056] In a specific embodiment, after the grouting is completed, the coagulation situation of the grouting liquid is judged to check the grouting quality. If it is unqualified, re - grouting is required; if it is qualified, the treatment of the lower layer 51 of the yellow mud is completed.

[0057] S6. After the consolidation of the lower layer 51 of the yellow mud, repeat steps S1 - S5 to complete the operations of directional drilling, liquid nitrogen freezing, grouting reinforcement, etc. for the upper layer 52 of the yellow mud, and take cores for grouting quality inspection to judge whether the treatment of the upper layer is qualified.

[0058] Specifically, in the roadway 101, the upper main road 7 is opened by drilling upward. The upper main road 7 is set at an angle of 60° with the horizontal. The upper main road 7 reaches the upper layer 52 of the yellow mud. Horizontal drilling is carried out in the upper layer 52 of the yellow mud. During the horizontal drilling process, the branch drilling method is adopted to drill an upper horizontal branch 71. The upper horizontal branch 71 extends horizontally along the upper layer 52 of the yellow mud and reaches the design position. Multiple upper horizontal branches 71 also need to be drilled. For example, in this embodiment, 4 upper horizontal branches 71 are also designed and arranged by directional drilling. The spacing between two adjacent upper horizontal branches 71 is 5 m, and the 4 upper horizontal branches 71 are distributed in a trident shape.

[0059] The drilling of the upper horizontal branch 71 and the subsequent operations of nitrogen injection, grouting, and consolidation are the same as those of the lower horizontal branch 61, and will not be elaborated here.

[0060] S7. After the yellow mud layer 5 is stabilized by grouting reinforcement and forms an overall load - bearing structure, install anchor cables and complete drilling, installing anchor cables, and tensioning and locking in sequence.

[0061] In a specific embodiment, after the yellow mud in the above area is consolidated, the same method is adopted, and the same steps are carried out in the second roadway 102, so that the entire yellow mud layer 5 is consolidated, and finally the treatment task of the loess layer 4 is successfully completed.

[0062] For the large-scale loess layer 4 area above the coal seam 1, the method of combining two roadways can be adopted, that is, first treat in the first roadway 101 and then treat in the second roadway 102; or the method of treating at intervals can be adopted to gradually complete the treatment of the entire area.

[0063] It should be understood that in practical applications, the use of the upper and lower layers for treatment in the present invention is only an example of an implementation manner and does not limit the treatment manner. If the thickness of the yellow mud layer 5 is large, it can be divided into multiple layers for treatment, and the tunneling and consolidation treatment of the yellow mud layer 5 are completed layer by layer using the same steps.

[0064] The details not described in the present invention are all conventional technical means well known to those skilled in the art.

[0065] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0066] The above-described embodiments are only used to describe the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A yellow mud tunnel roof drilling freezing-grouting-support integrated treatment method, characterized in that: The following steps are involved: S1. Divide the yellow mud layer into multiple layers according to its thickness and treat it layer by layer; S2. Drilling the main road in the tunnel upwards. After the main road reaches the yellow mud layer, drill horizontally and use a drill rod to drill a horizontal branch using a branch drilling method. S3, injecting liquid nitrogen into the yellow mud layer through the horizontal branch to achieve temporary freezing; S4, after the yellow mud around the previous horizontal branch is frozen, repeat steps S2 to S3 to complete the drilling, nitrogen injection and consolidation of the next horizontal branch; repeat the cycle to complete the drilling, nitrogen injection and consolidation of multiple horizontal branches until the lower layer of the yellow mud area is completely frozen; S5. Inject slurry into the frozen horizontal branches to make the yellow mud react with the slurry to achieve consolidation; S6, after the yellow mud layer of the layer is consolidated, repeat steps S1 to S5 to complete the directional drilling, liquid nitrogen freezing, and grouting reinforcement of the next yellow mud layer; S7. After the yellow mud layer is stabilized by grouting and forms an overall bearing structure, install the anchor cables, and complete drilling, anchor cable installation and tensioning and locking in sequence.

2. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of the yellow mud tunnel according to claim 1 is characterized in that: The main road is at an angle of 30° to 60° to the horizontal.

3. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of yellow mud tunnel according to claim 1 is characterized in that: The arrangement of the plurality of horizontal branches is in the shape of a harpoon.

4. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 1 is characterized in that: During the drilling process, casing is used as a drill rod. The drill rod includes an outer tube body and an inner tube body that are connected to each other. The outer tube body is provided with a number of outer tube holes with a diameter of 5 cm, and the distance between two adjacent outer tube holes is 20~30 cm.

5. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 4 is characterized in that: During the nitrogen injection and grouting process, liquid nitrogen or slurry is injected into the inner pipe body, and then the inner pipe is withdrawn, and the liquid nitrogen or slurry is transported to the yellow mud area through the holes in the outer pipe.

6. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 1 is characterized in that: In step S3, the nitrogen injection rate is 20-30 L / min, the nitrogen injection pressure is 5-10 MPa, the nitrogen injection time is 10-15 min, and the nitrogen injection range is 3-5 m along the radius of the drill pipe.

7. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 1 is characterized in that: In step S5, the grouting speed is 20-30 L / min, the grouting pressure is 5-10 MPa, the grouting time is 10-15 min, and the grouting range is 3-5 m along the radius of the drill pipe.

8. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 7 is characterized in that: The grouting setting time is 50~100min, and the strength after setting reaches 65~80MPa.

9. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 1, 7 or 8, characterized in that: The slurry is a mixed liquid of organic polymer material Marisan.

10. The integrated treatment method for drilling, freezing, grouting and supporting of the top plate of a yellow mud tunnel according to claim 1, characterized in that: According to the size of the yellow mud area above the coal seam, two or more tunnels are used to coordinate and manage the entire yellow mud area.

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