Combined pre-support rapid excavation method

Abstract

This invention discloses a combined pre-support rapid tunneling method, which includes determining the specific location of the roadway to be tunneled, and determining the location of the roof and sidewalls of the roadway; drilling multiple anchoring holes on the ground, including a first anchoring hole and a second anchoring hole, the first anchoring hole extending to the sidewall and the second anchoring hole extending to the roof; inserting expansion anchors into the anchoring holes, and after the end of the expansion anchor reaches a first preset position, the expansion anchor is radially expanded; drilling between two adjacent anchoring holes, and when the end of the drill bit reaches a second preset position, high-pressure water is introduced to both sides of the drill bit and filler material is introduced to the end of the drill bit, the high-pressure water crushes the coal and rock mass to form a void; the drill bit simultaneously retracts and sprays, the filler material enters the void to form a continuous filler layer extending along the length of the roadway, completing the pre-support of the roadway; after the filler layer solidifies, the roadway tunneling begins.

Description

Technical Field

[0001] This invention relates to the field of tunnel support technology, and in particular to a combined pre-support rapid tunneling method. Background Technology

[0002] Roadways are the foundation of underground coal mine production, serving important functions such as transportation and ventilation. Only a smooth and stable roadway system can provide a good operating space for the mine.

[0003] In related technologies, the working process of tunneling machine excavation is as follows: First, the tunneling device cuts the rock. After one cutting cycle, the tunneling machine stops and uses a manual hand-held single-unit anchor drilling rig or a tunneling and anchoring machine-mounted anchor bolting machine to support the rock bolts and anchor cables. Excavation is carried out first, followed by support.

[0004] However, it usually takes 7 to 15 minutes for the tunneling device to cut one cycle, and it takes more than half an hour to complete the support work such as anchor cables and anchor bolts, which seriously affects the efficiency of tunneling in underground roadways of coal mines. At the same time, there will be a gap in the roof after the tunneling device has tunneled, which poses a hidden danger to the support. Summary of the Invention

[0005] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a combined pre-support rapid tunneling method. This method involves pre-supporting the tunnel before tunneling, forming a continuous filling layer extending along the length of the tunnel at the roadway sidewalls and roof, ensuring the integrity and stability of the surrounding rock. Since the roof is already supported during tunneling, it avoids gaps between the roof and the tunnel walls after excavation, thus improving the safety and efficiency of the tunneling process.

[0006] The combined pre-support rapid tunneling method of this invention includes:

[0007] Determine the specific location of the roadway to be excavated, and determine the location of the roof and sidewalls of the roadway;

[0008] Multiple anchoring holes are drilled in the ground, including a first anchoring hole and a second anchoring hole. The first anchoring hole extends to the position of the side panel, and the second anchoring hole extends to the position of the top plate.

[0009] The expansion anchor is inserted into the anchoring hole, and after the end of the expansion anchor reaches the first preset position, the expansion anchor is expanded radially.

[0010] Drilling is performed between two adjacent anchoring holes. When the end of the drill bit reaches the second preset position, high-pressure water is introduced to both sides of the drill bit and filler material is introduced to the end of the drill bit. The high-pressure water breaks up the coal and rock mass to form a void.

[0011] The drill bit simultaneously retracts and sprays air, and the filler material enters the empty layer to form a continuous filler layer extending along the length of the tunnel, thus completing the pre-support of the tunnel.

[0012] After the filling layer solidifies, the tunnel excavation begins.

[0013] The combined pre-support rapid tunneling method of this invention pre-supports the roadway before tunneling, so that the roadway sidewalls and roof form a continuous filling layer extending along the length of the roadway, ensuring the integrity and stability of the roadway surrounding rock. Since the roof has been supported during tunneling, the occurrence of headspace after tunneling is avoided, thus improving the safety and efficiency of tunneling.

[0014] In some embodiments, the filler includes a first filler and a second filler. When the drill bit simultaneously retracts and swivels, the first filler enters the empty layer to form a wall on the side of the sidewall away from the tunnel. A portion of the expansion anchor located in the first anchor hole is located within the wall. When the drill bit simultaneously retracts and swivels, the second filler enters the empty layer to form a top wall above the top plate. A portion of the expansion anchor located in the second anchor hole is located within the top wall. The wall and the top wall constitute the filler layer.

[0015] In some embodiments, the wall is a rigid wall and the roof is a flexible roof.

[0016] In some embodiments, the first filler is high-pressure cement slurry, which impacts the coal body and forms a coal slurry composite wall with the coal body. After the coal slurry composite wall solidifies, it forms the rigid wall. The second filler is line-x coating, which is sprayed onto the inner wall surface of the second anchoring hole and the inner wall surface of the void layer to quickly bond the inner wall surface of the second anchoring hole and the inner wall surface of the void layer, thereby forming the flexible top wall.

[0017] In some embodiments, after drilling the anchoring hole, the lower end of the anchoring hole is enlarged.

[0018] In some embodiments, the expansion rate of the lower end of the expansion anchor is greater than the expansion rate of the other parts of the expansion anchor.

[0019] In some embodiments, the expansion anchor bolt includes a normal anchoring section and an enlarged head anchoring section, wherein the radius of the enlarged head anchoring section after expansion is larger than the radius of the normal anchoring section after expansion.

[0020] In some embodiments, the expansion anchor includes a rod body and a plurality of barbs, the lower ends of which are rotatably connected to the lower part of the rod body, allowing the barbs to swing up and down on the rod body within a range of 0 to 90°. When the expansion anchor moves downward along the anchoring hole and the barbs contact the hole wall, the barbs adhere to the rod body under the compression of the anchoring hole. When the barbs move downward to the enlarged section of the anchoring hole, the barbs swing outward under their own weight.

[0021] In some embodiments, the barbs are divided into multiple rings, each ring including at least two barbs spaced circumferentially along the rod, and the multiple rings of barbs spaced axially along the rod.

[0022] In some embodiments, the combined pre-support rapid tunneling method further includes reinforcing support behind the tunneling face after the tunnel is excavated. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the combined pre-support rapid tunneling method according to an embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram of the tunnel, filling layer, and anchoring holes according to an embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram of an expansion anchor bolt according to an embodiment of the present invention.

[0026] Figure 4 This is the present invention. Figure 3 A magnified view of part a in the middle.

[0027] Figure label:

[0028] Lane 1;

[0029] Anchor hole 2; First anchor hole 21; Second anchor hole 22;

[0030] Infill layer 3; Wall 31; Ceiling wall 32;

[0031] 4. Expansion anchor bolt; 41. Rod body; 42. Barbs. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0033] The combined pre-support tunneling method of the present invention is described below with reference to the accompanying drawings.

[0034] like Figure 1 and Figure 2 As shown, the combined pre-support tunneling method of this invention includes:

[0035] S1. Determine the specific location of the roadway 1 to be excavated, and determine the location of the roof and sides of the roadway 1. Specifically, the specific location of the roadway 1 to be excavated is determined by geological transparency technology, the two sides of the roadway 1 are determined as the location of the sides of the roadway 1, and the top of the roadway 1 is determined as the location of the roof of the roadway 1.

[0036] S2. Drill multiple anchor holes 2 in the ground. The anchor holes 2 include first anchor holes 21 and second anchor holes 22. The first anchor holes 21 extend to the side wall, and the second anchor holes 22 extend to the top of the roadway. Specifically, the anchor holes 2 are divided into multiple rows, and the multiple rows of anchor holes 2 are distributed at intervals along the length of the roadway 1. Each row of anchor holes 2 includes multiple anchor holes 2 distributed at intervals along the width of the roadway 1. Among them, the anchor holes 2 located on both sides are the first anchor holes 21, which extend downward to the side wall of the roadway 1. The anchor holes 2 located in the middle are the second anchor holes 22, which extend downward to the top of the roadway 1.

[0037] It should be noted that the drilling of anchor holes 2 is carried out according to the actual geological conditions and the conditions of the roadway 1 to be excavated. For example, anchor holes 2 in the same row are arranged at intervals along a straight line, at intervals along an arc, or at intervals along a wavy line.

[0038] S3. Insert the expansion anchor into the anchoring hole 2. After the end of the expansion anchor reaches the first preset position, the expansion anchor is radially expanded. Specifically, when the lower end of the expansion anchor reaches the bottom of the anchoring hole 2, the lower end of the expansion anchor is radially expanded to complete the anchor support.

[0039] S4. Drilling is performed between two adjacent anchor holes 2. When the end of the drill bit reaches the second preset position, high-pressure water is introduced to both sides of the drill bit and filler material is introduced to the end of the drill bit. The high-pressure water breaks up the coal and rock mass to form a void. Specifically, after the bottom end of the drill bit reaches the position of the sidewall or the roof, the high-pressure water at both ends of the drill bit breaks up the coal and rock mass to form a void on one side or above the roadway 1. The lower end of the expansion anchor is located in the void. In other words, the high-pressure water at both ends of the drill bit breaks up the coal and rock mass to form a void at the sidewall and roof positions of the roadway 1.

[0040] S5. Simultaneously, the drill bit retracts and swivels, allowing filler material to enter the empty layer to form a continuous filler layer 3 extending along the length of roadway 1, thus completing the pre-support of roadway 1. Specifically, the drill bit retracts and swivels simultaneously, allowing filler material to be introduced into the empty layer from the end of the drill bit, bonding the coal and rock mass, filler material, and expansion bolts together to complete the pre-support of roadway 1.

[0041] S6. After the filling layer 3 has solidified, begin excavating tunnel 1.

[0042] The combined pre-support rapid tunneling method of this invention pre-supports the roadway 1 before tunneling, so that the sidewall and roof of the roadway 1 form a continuous filling layer 3 extending along the length of the roadway 1, ensuring the integrity and stability of the surrounding rock of the roadway 1. When tunneling the roadway 1, since the roof has been supported, the gap between the roof and the roof is avoided after tunneling, thus improving the safety and efficiency of tunneling.

[0043] In some embodiments, the filler includes a first filler and a second filler. When the drill bit is simultaneously retracting and swivel-spraying, the first filler enters the empty layer to form a wall 31 on the side of the sidewall away from the roadway 1. A portion of the expansion anchor located in the first anchor hole 21 is located within the wall 31. When the drill bit is simultaneously retracting and swivel-spraying, the second filler enters the empty layer to form a top wall 32 above the top plate. A portion of the expansion anchor located in the second anchor hole 22 is located within the top wall 32. The wall 31 and the top wall 32 constitute the filler layer 3.

[0044] It should be noted that after the first filler enters the empty layer at the side wall position, the first filler bonds the coal and rock mass and expansion anchor bolts at the side wall position to form a continuous wall 31 extending along the length of roadway 1, thus completing the pre-support of the side wall of roadway 1; after the second filler enters the empty layer at the roof position, the second filler bonds the coal and rock mass and expansion anchor bolts at the roof position to form a continuous roof wall 32 extending along the length of roadway 1, thus completing the pre-support of the roof of roadway 1.

[0045] By selecting different fillers and filling methods, the wall 31 and the roof slab can have different characteristics according to the actual situation. For example, after the tunnel 1 is excavated, the surrounding rock at the roof slab of the tunnel 1 is prone to subsidence, which causes the roof wall 32 to deform. Therefore, the roof wall 32 needs to have a certain degree of flexibility to prevent the roof wall 32 from cracking or even breaking when the surrounding rock at the roof slab of the tunnel 1 subsides.

[0046] In some embodiments, the wall 31 is a rigid wall 31, and the top wall 32 is a flexible top wall 32.

[0047] In one specific embodiment, the first filler is high-pressure cement slurry, which impacts the coal body and forms a coal slurry composite wall 31 with the coal body. After the coal slurry composite wall 31 solidifies, it forms a rigid wall 31. The second filler is line-x coating, which is sprayed onto the inner wall surface of the second anchoring hole 22 and the inner wall surface of the void layer to quickly bond the inner wall surface of the second anchoring hole 22 and the inner wall surface of the void layer, thereby forming a flexible top wall 32.

[0048] Understandably, after the coal slurry composite wall 31 solidifies, it forms a rigid wall 31 with high compressive strength, which is used to bear the pressure on both sides and the top of the roadway 1. The line-x coating forms a flexible roof wall 32 with a certain degree of flexibility. When the surrounding rock at the top of the roadway 1 sinks, the flexible roof wall 32 is less likely to crack or break, thus improving the safety of the roof wall 32.

[0049] In some embodiments, after drilling the anchor hole 2, the lower end of the anchor hole 2 is enlarged so that the lower end of the anchor hole 2 is an enlarged section.

[0050] In some embodiments, the expansion rate of the lower end of the expansion anchor is greater than the expansion rate of the other parts of the expansion anchor. Optionally, the expansion anchor includes a normal anchoring section and an enlarged head anchoring section, wherein the radius of the enlarged head anchoring section after unfolding is greater than the radius of the normal anchoring section after unfolding.

[0051] It is understandable that by enlarging the lower end of anchor hole 2, the anchor rod can produce a support effect similar to that of an enlarged anchor rod, thereby improving the ultimate bearing capacity of the anchor rod.

[0052] like Figure 3 and Figure 4 As shown, in a specific embodiment, the expansion anchor 4 includes a rod body 41 and a plurality of barbs 42. The lower ends of the plurality of barbs 42 are rotatably connected to the lower part of the rod body 41, so that the barbs 42 can swing up and down in the range of 0 to 90° on the rod body 41. When the expansion anchor 4 moves downward along the anchor hole 2 and the barbs 42 contact the hole wall of the anchor hole 2, the barbs 42 are pressed against the rod body 41 under the pressure of the anchor hole 2, so as to avoid the barbs 42 affecting the downward movement of the expansion anchor 4 along the anchor hole 2. When the barbs 42 move downward to the enlarged hole section of the anchor hole 2, the barbs 42 swing outward under the action of their own gravity.

[0053] Furthermore, the barbs 42 are divided into multiple rings, each ring of barbs 42 includes at least two barbs 42 that are circumferentially spaced along the rod body 41, and the multiple rings of barbs 42 are spaced along the axial direction of the rod body 41.

[0054] In some embodiments, the combined pre-support rapid tunneling method further includes reinforcing the tunnel 1 behind the tunneling face after tunneling, in order to enhance the safety of the tunnel 1. Specifically, based on the calculated location of reinforcement, holes are drilled into the wall 31 at the reinforcement location and anchor bolts are inserted to reinforce the wall 31 and the surrounding rock.

[0055] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0056] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0057] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0058] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0059] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0060] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A combined pre-support rapid tunneling method, characterized in that, include: Determine the specific location of the roadway to be excavated, and determine the location of the roof and sidewalls of the roadway; Multiple anchoring holes are drilled in the ground, including a first anchoring hole and a second anchoring hole. The first anchoring hole extends to the position of the side panel, and the second anchoring hole extends to the position of the top plate. The lower end of the anchoring holes is enlarged. An expansion anchor rod is placed into the anchoring hole. The expansion anchor rod includes a rod body and multiple barbs. The lower ends of the multiple barbs are rotatably connected to the lower part of the rod body, so that the barbs can swing up and down on the rod body within a range of 0 to 90°. When the expansion anchor rod moves downward along the anchoring hole and the barbs contact the hole wall, the barbs adhere to the rod body under the compression of the anchoring hole. When the end of the expansion anchor rod reaches the first preset position and the barbs enter the enlarged section of the anchoring hole, the barbs swing outward under their own weight, causing the expansion anchor rod to expand radially. Drilling is performed between two adjacent anchoring holes. When the end of the drill bit reaches the second preset position, high-pressure water is introduced to both sides of the drill bit and filler is introduced to the end of the drill bit. The high-pressure water breaks up the coal and rock mass to form a void layer on the side of the roadway away from the roadway and above the roof. The drill bit simultaneously retracts and sprays air, and the filler enters the empty layer to form a continuous filler layer extending along the length of the roadway, so that the coal and rock mass, the filler, and the expansion anchor are bonded together to complete the pre-support of the roadway; the filler layer includes a wall located on the side of the sidewall away from the roadway and a top wall located above the roof. After the filling layer solidifies, the tunnel excavation begins; The filler includes a first filler and a second filler. When the drill bit simultaneously retracts and jerks, the first filler material enters the empty layer to form the wall on the side of the rib away from the tunnel, and a portion of the expansion anchor located in the first anchor hole is located within the wall. When the drill bit simultaneously retracts and oscillates, the second filler material enters the empty layer to form the top wall above the top plate, and a portion of the expansion anchor located in the second anchoring hole is located within the top wall. The wall and the top wall constitute the filling layer; the wall is a rigid wall, and the top wall is a flexible top wall; The first filler is high-pressure cement slurry. The high-pressure cement slurry impacts the coal body and forms a coal slurry composite wall with the coal body. After the coal slurry composite wall solidifies, it forms the rigid wall. The second filler is line-x coating, which is sprayed onto the inner wall of the second anchoring hole and the inner wall of the empty layer to quickly bond the inner wall of the second anchoring hole and the inner wall of the empty layer, thereby forming the flexible top wall.

2. The combined pre-support rapid tunneling method according to claim 1, characterized in that, The expansion rate at the lower end of the expansion anchor is greater than the expansion rate of the other parts of the expansion anchor.

3. The combined pre-support rapid tunneling method according to claim 2, characterized in that, The expansion anchor bolt includes a normal anchoring section and an enlarged head anchoring section, wherein the radius of the enlarged head anchoring section after expansion is larger than the radius of the normal anchoring section after expansion.

4. The combined pre-support rapid tunneling method according to claim 1, characterized in that, The barbs are divided into multiple rings, each ring including at least two barbs spaced apart circumferentially along the rod body, and the multiple rings of barbs spaced apart axially along the rod body.

5. The combined pre-support rapid tunneling method according to any one of claims 1-4, characterized in that, It also includes reinforcing support behind the tunneling face after the tunnel is excavated.

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