Roadway wall caving control method

Abstract

The invention discloses a roadway wall caving control method which comprises the following steps: S1, after roadway tunneling, spraying a high-toughness composite material on a wall part so as to improve the toughness of the surface of the wall part; s2, pre-stress full-length anchoring supporting is conducted on the roadway through anchor rods with the ultrahigh elongation rate or anchor cables with the ultrahigh elongation rate, and high-rigidity and large-area steel belts or steel beams are used for connection so that the anchoring force and the overall surface protection capacity of the anchor rods and the anchor cables can be improved; s3, before working face stoping, a roadway roof is punched to form a pressure relief hole, high-pressure water is introduced into the pressure relief hole so that a rock stratum in the pressure relief hole can be broken, high-pressure water jet is introduced into the pressure relief hole so that the rock stratum can be further broken, and sufficient pressure relief can be conducted on the roof; the roadway wall caving control method has the advantages of being simple in step, good in control effect and the like.

Description

Technical Field

[0001] The present invention relates to the field of deep earth energy development engineering, and in particular to a three-level control method for large-section tunnel spalling. Background Art

[0002] With the development of intelligent coal mining technology and the requirements of energy supply, the existing coal mining equipment is relatively large. In order to transport the equipment to the coal mining face, the cross-section of the mining tunnel is getting larger and larger, exceeding 25 square meters. For some large mining height and full thickness mining faces in the mining area, a strong dynamic pressure effect is generated during the mining process of the working face. The coal seam is generally strong, which leads to serious spalling in the mining tunnel, affecting the intelligent mining of the working face. It is urgent to solve this problem.

[0003] In the related art, the tunnel support adopts the method of reinforcing anchor rods and anchor cables, which is easy to cause large-scale falling of the unsupported part between the anchor rods and the anchor cables, resulting in poor support effect. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention proposes a tunnel spalling control method with strong supporting effect and stable supporting.

[0006] The tunnel spalling control method according to an embodiment of the present invention includes: S1: after tunnel excavation, spraying a composite material with high toughness on the sidewall to improve the toughness of the sidewall surface; S2: using an anchor rod with ultra-high elongation or an anchor cable with ultra-high elongation to perform prestressed full-length anchor support on the tunnel to improve the stability of the tunnel, and two adjacent anchor rods or anchor cables are connected by a high-rigidity steel belt or steel beam to improve the support stiffness and support surface area of ​​the anchor rods or anchor cables; S3: before the working face is mined, drilling holes in the tunnel roof to form pressure relief holes, passing high-pressure water into the pressure relief holes to fracture the rock formation in the pressure relief holes, and passing a high-pressure water jet into the pressure relief holes to further break the rock formation to relieve pressure on the roof.

[0007] The tunnel spalling control method of the embodiment of the present invention is arranged with steps S1 to S3, wherein the brittleness of the coal body on the surface of the sidewall is modified and controlled by composite materials, while the ejection and spalling of the coal body are suppressed; secondly, timely support and control are performed by high prestressed composite anchor rods and cables to reduce the expansion deformation in the initial stage of excavation; finally, the mining stress control of the coal mining working face is transferred by multi-source pressure relief to reduce the force of the tunnel from the source, thereby solving the problem of sidewall spalling at large mining height and ultra-large section, ensuring intelligent mining of the working face, and improving mining efficiency and mining safety.

[0008] In some embodiments, in step S1, the bonding strength between the composite material and the sidewall is not less than 3 MPa, the flexural strength of the composite material is not less than 5 MPa, and the spraying thickness of the composite material is 3 mm-5 mm.

[0009] In some embodiments, in step S2, the yield load of the anchor rod is not less than 350 kN, the preload applied to the anchor rod is greater than 40% of the yield load of the anchor rod, the maximum force elongation of the anchor rod is ≥15%, and the anchor rod is connected with a high-rigidity W-shaped steel belt.

[0010] In some embodiments, in step S2, the breaking force of the anchor cable is not less than 585 kN, the preload force applied to the anchor cable is greater than 40% of the cable body yield load of the anchor cable, the maximum force elongation of the anchor cable is ≥7%, and the anchor cable is connected with a high-rigidity steel beam.

[0011] In some embodiments, in step S3, a hole is drilled in the top plate by using a drill rig to form the pressure relief hole, and high-pressure water or a high-pressure water jet is injected into the pressure relief hole by using a pump.

[0012] In some embodiments, in step S3, the diameter of the pressure relief hole is 56 mm-200 mm, and the length of the pressure relief hole is 20 m-200 m.

[0013] In some embodiments, in step S3, the number of the pressure relief holes is multiple, and the multiple pressure relief holes are arranged in multiple rows along the length direction of the lane, and each row includes a plurality of pressure relief holes arranged at intervals along the width direction of the lane.

[0014] In some embodiments, in step S2, drilling, grouting, pre-tightening and other anchoring support operations are performed using integrated drilling and anchoring.

[0015] In some embodiments, the composite material may be a silicate polyurea composite fiber material. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flow chart of a laneway slab control method according to an embodiment of the present invention.

[0017] Figure 2 It is a top view of the working face mining of the tunnel spalling control method according to an embodiment of the present invention.

[0018] Figure 3 It is a cross-sectional view of a mining tunnel of a tunnel spalling control method according to an embodiment of the present invention.

[0019] Tunnel spalling control method 100; coal mining working face 1; mining tunnel 2; composite material 3; anchor rod 4; pressure relief hole 5. DETAILED DESCRIPTION

[0020] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0021] The following describes a lane flap control method 100 according to an embodiment of the present invention with reference to the accompanying drawings.

[0022] like Figure 1-3 As shown, the lane collapse control method 100 according to an embodiment of the present invention includes steps S1 to S3.

[0023] S1: After the tunnel is excavated, the sidewall is sprayed with a composite material 3 having high toughness to improve the toughness of the sidewall surface. Figure 1 and Figure 3 As shown, after the mining tunnel 2 is excavated, the composite material 3 can be sprayed on the side of the mining tunnel 2. The composite material 3 has good adhesion and toughness, and forms a tough protective layer on the side to improve the toughness of the side surface. When the mining tunnel 2 undergoes a large deformation, it still maintains toughness, and the side does not experience brittle fracture, thereby suppressing the ejection or falling of the coal body on the side after destruction.

[0024] S2: Using anchor rods 4 with ultra-high elongation or anchor cables with ultra-high elongation to carry out prestressed full-length anchor support for the tunnel, so as to improve the stability of the tunnel. Two adjacent anchor rods 4 or anchor cables are connected by high-rigidity steel belts or steel beams, so as to improve the support stiffness and support surface area of ​​the anchor rods 4 or anchor cables. Specifically, Figure 2 and Figure 3 As shown, after the composite material 3 is sprayed, the tunnel is supported by anchor rods 4 or anchor cables, thereby effectively improving the stability of the tunnel and preventing the tunnel roof and side from being deformed or collapsed due to uneven force. Adjacent anchor rods or anchor cables are connected by high-rigidity, large-area steel belts or steel beams to form an integral support system, thereby enhancing the integrity and stability of the support system and improving the support effect and support surface area.

[0025] S3: Before the working face is mined, the tunnel roof is perforated to form a pressure relief hole 5, high-pressure water is introduced into the pressure relief hole 5 to fracture the rock formation in the pressure relief hole 5, and a high-pressure water jet is introduced into the pressure relief hole 5 to further break the rock formation, so as to relieve the pressure on the roof. Specifically, Figure 1 and Figure 3As shown, before the working face is mined, the tunnel roof is drilled to form a pressure relief hole 5, and high-pressure water is introduced into the pressure relief hole 5 to fracture the rock strata in the hole of the pressure relief hole 5. The rock strata are then crushed by a high-pressure water jet, thereby achieving two-stage crushing and pressure relief, cutting off the connection between the hard roof of the large mining height mining face and the tunnel, reducing the strong mining stress, and reducing the stress acting on the side of the tunnel from the source.

[0026] The tunnel spalling control method 100 of the embodiment of the present invention is arranged with steps S1 to S3, and the brittleness of the coal body on the surface of the spalling part is modified and controlled by the composite material 3, and the ejection and spalling of the coal body on the spalling part are suppressed at the same time. Secondly, the high prestressed anchor rods 4 are used for timely support and control to reduce the expansion deformation in the initial stage of excavation, thereby reducing the force of the tunnel from the source and improving the mining efficiency and mining safety.

[0027] The tunnel spalling control method 100 of the embodiment of the present invention, after spraying the composite material 3, the surface toughness of the spalling part will be significantly improved, and its shear and tensile resistance will be enhanced, which will help reduce the risk of the spalling part being broken or falling off due to the vibration and pressure generated during the tunnel excavation process. After spraying the composite material 3, the surface of the spalling part has good adhesion and toughness, which provides a support basis for the support work of the anchor rod 4 or anchor cable, so that the anchor cable and anchor rod 4 can be more effectively fixed on the spalling part, thereby ensuring the stability and reliability of the support structure. The presence of the composite material 3 can also reduce the corrosion and wear of the support material due to direct exposure to harsh environments, thereby extending the service life of the support structure.

[0028] In some embodiments, in step S1, the bonding strength between the composite material 3 and the side part is not less than 3MPa. Specifically, during tunnel excavation and subsequent mining, the side part will be subjected to various stresses, such as ground pressure, water pressure, etc. If the bonding strength is lower than 3MP, the composite material 3 may fall off the side part, resulting in support failure. Therefore, the bonding strength between the composite material 3 and the side part is not less than 3MPa. It can ensure that a stable bond is formed between the composite material 3 and the side part, and the durability of the composite material 3 enables it to withstand various stresses for a long time without being damaged.

[0029] In some embodiments, in step S1, the flexural strength of the composite material 3 is not less than 5 MPa. Specifically, the flexural strength is a measure of the material's ability to resist bending stress. During tunnel excavation, the sidewalls may be subjected to bending stress from different directions. If the flexural strength of the composite material 3 is less than 5 MPa, it may break under the action of the bending stress, thereby affecting the support effect. Therefore, the flexural strength of the composite material 3 is not less than 5 MPa, which can better resist external shocks and vibrations and improve the overall performance of the tunnel support.

[0030] In some embodiments, in step S1, the spraying thickness of the composite material 3 is 3mm-5mm. Specifically, the spraying thickness of the composite material 3 can be any one of 3mm, 4mm, and 5mm. If the spraying thickness is less than 3mm, the composite material 3 will be too thin and the composite material 3 will not provide sufficient protection. If the spraying thickness is greater than 5mm, the composite material 3 will be too thick, which may increase costs and reduce construction efficiency. Therefore, the spraying thickness of the composite material 3 is 3mm-5mm, which can ensure that the composite material 3 can completely cover the surface of the side part, forming a uniform protective layer, which helps to reduce the weathering, corrosion and other damage to the side part due to exposure to the outside, and within the thickness range of 3mm-5mm, the performance of the composite material 3 can be fully exerted.

[0031] In some embodiments, in step S2, the yield load of the anchor rod 4 with ultra-high elongation is not less than 350kN, the pre-tightening force applied to the anchor rod 4 is greater than 40% of the yield load of the anchor rod 4, the maximum force elongation of the anchor rod 4 is ≥15%, and the anchor rod 4 is connected by a high-rigidity, large-area W-shaped steel belt. Specifically, the yield load of the anchor rod 4 is not less than the yield load of 350kN, which can ensure that the anchor rod 4 will not easily undergo plastic deformation or damage when subjected to various stresses generated during tunnel excavation and mining, thereby improving the stability and reliability of the anchor rod 4 support structure, and improving the resistance of the anchor rod 4 to external impact and vibration, and reducing the risk of safety accidents caused by the failure of the anchor rod 4. In addition, after the anchor rod 4 is installed, a pre-tightening force can be applied to the anchor rod 4, and the pre-tightening force is greater than 40% of the yield load of the anchor rod 4, ensuring that the anchor rod 4 can maintain sufficient tightening force when subjected to external forces, and is not easy to loosen or fall off, thereby improving the support effect and reducing the deformation and collapse risks of the tunnel roof and the side. Secondly, the maximum force elongation of anchor rod 4 is ≥15%, which can ensure that anchor rod 4 has a certain deformation capacity when subjected to external force, so that anchor rod 4 can absorb and disperse energy by deformation when subjected to impact or vibration, thereby extending the service life of anchor rod 4. Finally, W-shaped steel belt has high rigidity, can effectively transmit and disperse stress, and prevent support failure caused by local stress concentration. Moreover, large-area W-shaped steel belt can increase the contact area with the surrounding rock of the tunnel, and improve the overall stability and bearing capacity of the support system. Therefore, the support method of connecting anchor rods with W-shaped steel belts can significantly improve the overall stability of the tunnel, prevent deformation or collapse of the tunnel roof and side due to uneven force, increase the surface area and rigidity of the support system, and extend the service life of the support structure.

[0032] In some embodiments, in step S2, the breaking force of the anchor cable is not less than 585kN, the pre-tightening force applied to the anchor cable is greater than 40% of the yield load of the anchor cable, the maximum force elongation of the anchor cable is ≥7%, and the anchor cable is connected with a high-rigidity steel beam. Specifically, the breaking force of the anchor cable is not less than 585kN, which can ensure that the anchor cable will not easily break when it is subjected to various tensile forces generated during tunnel excavation and mining, thereby maintaining the stability and reliability of the support structure, and also improving the ability to resist external shocks and vibrations, reducing the risk of safety accidents caused by anchor cable failure, extending the service life of the anchor cable, and ensuring the safety and stability of the tunnel. In addition, after the anchor cable is installed, a pre-tightening force can be applied to the anchor cable, and the pre-tightening force is greater than 40% of the yield load of the anchor cable, which can ensure that the anchor cable can maintain sufficient tightening force when subjected to external forces, and is not easy to loosen or fall off, thereby improving the stability of the anchor cable and reducing the deformation and collapse risks of the tunnel roof and side. Secondly, the maximum force elongation of the anchor cable is ≥7%, which can ensure that the anchor cable has a certain deformation capacity when subjected to external force, so as to better adapt to the deformation and displacement of the tunnel. When the anchor cable is impacted or vibrated, the energy is absorbed and dispersed through the deformation of the anchor cable, reducing the risk of damage to the anchor cable, increasing the service life of the anchor cable and reducing the support cost. Finally, by connecting the anchor cables with high-rigidity steel beams, a more stable support system can be formed, which significantly improves the stiffness of the support system, thereby better controlling the deformation of the tunnel surrounding rock, and the steel beam connection can increase the bearing capacity of the support system, so that the support structure can better resist the pressure and deformation of the tunnel surrounding rock.

[0033] In some embodiments, in step S3, a drilling rig is used to drill a hole in the roof to form a pressure relief hole 5, and a pump is used to inject high-pressure water or a high-pressure water jet into the pressure relief hole 5. Thus, the roof is drilled by a drilling rig to form a pressure relief hole 5, and a pump is used to provide injection power for the high-pressure water or the high-pressure water jet, so that the tunnel spalling control method 100 is more reasonably set.

[0034] In some embodiments, in step S3, the aperture of the pressure relief hole 5 is 56mm-200mm. Specifically, the aperture of the pressure relief hole 5 can be any one of 56mm, 60mm, 70mm, 80mm, 90mm, 100mm, 150mm, and 200mm. When the aperture of the pressure relief hole 5 is less than 56mm, the aperture of the pressure relief hole 5 will be too small, increasing the construction difficulty and cost of the drilling rig. When the aperture of the pressure relief hole 5 is greater than 200mm, the aperture of the pressure relief hole 5 will be too large, increasing the risk and maintenance cost during the drilling process. Therefore, setting the aperture diameter range of 56mm-200mm can ensure that the pressure relief hole 5 has enough area to release the high pressure stress inside the top plate. And according to the hardness, thickness and integrity of the rock formation, etc., the pressure relief holes 5 of different apertures are selected. For example, when the rock formation is hard and the integrity is good, a larger aperture diameter can be selected to improve the pressure relief effect, and when the rock formation is soft and severely broken, a smaller aperture diameter can be selected to avoid excessive damage to the rock formation.

[0035] In some embodiments, in step S3, the length of the pressure relief hole 5 is 20m-200m. Specifically, the length of the pressure relief hole 5 can be any one of 20m, 40m, 60m, 80m, 100m, 120m, 140m, 160m, 180m, and 200m, and the length of the pressure relief hole 5 can be selected according to actual conditions, for example: in the case of hard rock formations with good integrity, or long tunnels and deep mining depths, longer pressure relief holes 5 can be drilled, and in the case of soft rock formations with severe crushing, the length of the pressure relief hole 5 can be shortened to reduce risks and costs during construction.

[0036] In some embodiments, in step S3, the number of the pressure relief holes 5 is multiple, and the multiple pressure relief holes 5 are arranged in multiple rows along the length direction of the lane, and each row includes a plurality of pressure relief holes 5 arranged in a spaced relationship along the width direction of the lane. Specifically, Figure 1 and Figure 3 As shown, the pressure relief holes 5 are arranged in multiple rows along the front-to-back direction, and each row includes a plurality of pressure relief holes 5 arranged along the left-to-right direction. Thus, the pressure relief area of ​​the roof is increased through the plurality of pressure relief holes 5, and the high pressure stress inside the tunnel roof is effectively released, the stress concentration around the tunnel is reduced, and the risk of deformation and damage to the tunnel is reduced. In addition, the plurality of pressure relief holes 5 can form a plurality of stress release channels, so that the stress is more evenly distributed around the tunnel, thereby improving the overall stability of the tunnel.

[0037] In some embodiments, in step S2, drilling, grouting, pre-tightening and other anchoring support operations are performed by using drilling-anchor integration. Thus, multiple processes such as drilling, grouting and anchoring are integrated into one by using drilling-anchor integration technology, so that the anchor 4 support is completed at one time, the construction efficiency is improved, the waiting time and manual operation during the construction process are reduced, thereby shortening the construction period and reducing the construction cost.

[0038] In some embodiments, the composite material 3 may be a silicate polyurea composite fiber material. Specifically, the composite material 3 may be a silicate modified polyurea composite fiber material, which combines the hardness of silicate and the toughness of polyurea, so that the composite material 3 has higher strength and toughness, thereby improving the toughness and strength of the butt.

[0039] The construction steps of the tunnel spalling control method 100 of the embodiment of the present invention are as follows:

[0040] After tunnel excavation, high-toughness and strong-adhesion silicate-modified polyurea composite fiber material is first sprayed on the side of the tunnel. Before completing the anchor rod 4 and anchor cable support, the entire space is covered with the side of the tunnel anchor rod 4 and anchor cable support and the unsupported coal body. The bonding strength of the sprayed material with the coal is not less than 3MPa, the bearing capacity is not less than the metal mesh, the flexural strength is not less than 5MPa, and the spraying thickness is 3mm to 5mm. It still maintains toughness after large deformation and does not break brittlely. On the one hand, it improves the integrity of the side and the entire space, and on the other hand, it suppresses the ejection or falling of the coal body after damage. Secondly, high-strength and ultra-high elongation anchor bolts 4 and anchor cables are promptly supported in the gangway. The yield load of anchor bolts 4 is not less than 350kN, and the breaking force of anchor cables is not less than 585kN. High preload is applied to anchor bolts 4 and anchor cables. The preload is more than 40% of the yield load of anchor bolts 4 / cable body. The maximum force elongation of anchor bolts 4 is ≥15%, and the maximum force elongation of anchor cables is ≥7%. Finally, before the working face is mined, multi-source pressure relief holes 5 are arranged on the top plate of the tunnel to relieve the hard The rock strata are decompressed by hydraulic fracturing and high-pressure water jet punching. The diameter of the drill hole is 56mm to 200mm and the length of the drill hole is 20m to 200m. The hydraulic fracturing destroys the hard rock strata far away from the tunnel. The high-pressure water jet punching increases the crushing energy, realizes two-stage crushing and decompression, cuts off the connection between the hard roof of the large mining height recovery working face and the tunnel, reduces the strong mining stress, and reduces the stress acting on the side of the tunnel from the source. After the decompression is completed, the coal mining working face 1 is mined. Therefore, the composite material 3 modifies and controls the brittleness of the coal body on the side surface, and at the same time inhibits the ejection and shedding of the coal body. The high prestressed anchor rod 4 anchor cable is used for timely support and control to reduce the expansion deformation in the early stage of excavation. Through multi-source decompression transfer, the mining stress control of the coal mining working face is reduced from the source, thereby solving the problem of shearing of the side of the large mining height and super-large section, and ensuring intelligent mining of the working face.

[0041] In summary, the control method of the invention can be used to improve the active support effect of anchor rods 4 and anchor cables, the brittleness of the coal body in the side and the confining pressure of the unsupported space, reduce the impact of coal mining on the tunnel, effectively control the shedding of coal body in the side, and ensure intelligent mining of the working face.

[0042] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0043] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0044] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0046] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0047] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A tunnel slab control method, characterized in that: include: S1: After the tunnel is excavated, a composite material with high toughness is sprayed on the sidewall to improve the toughness of the sidewall surface; S2: Using anchor rods with ultra-high elongation or anchor cables with ultra-high elongation to perform prestressed full-length anchor support on the tunnel, so as to improve the stability of the tunnel, and two adjacent anchor rods or anchor cables are connected by high-rigidity steel belts or steel beams, so as to improve the support stiffness and support surface area of ​​the anchor rods or anchor cables; S3: Before mining at the working face, the tunnel roof is drilled to form a pressure relief hole, high-pressure water is passed through the pressure relief hole to fracture the rock formation in the pressure relief hole, and a high-pressure water jet is passed through the pressure relief hole to further break the rock formation, so as to relieve pressure on the roof.

2. The tunnel rib control method according to claim 1, characterized in that: In step S1, the bonding strength between the composite material and the side part is not less than 3 MPa, the flexural strength of the composite material is not less than 5 MPa, and the spraying thickness of the composite material is 3 mm-5 mm.

3. The tunnel rib control method according to claim 1, characterized in that: In step S2, the yield load of the anchor rod is not less than 350 kN, the preload applied to the anchor rod is greater than 40% of the yield load of the anchor rod, the maximum force elongation of the anchor rod is ≥15%, and the anchor rod is connected with a high-rigidity W-shaped steel belt.

4. The tunnel rib control method according to claim 1, characterized in that: In step S2, the breaking force of the anchor cable is not less than 585 kN, the pre-tightening force applied to the anchor cable is greater than 40% of the cable body yield load of the anchor cable, the maximum force elongation of the anchor cable is ≥7%, and the anchor cable is connected by a high-rigidity steel beam.

5. The tunnel rib control method according to claim 1, characterized in that: In step S3, a hole is drilled in the top plate by using a drilling machine to form the pressure relief hole, and high-pressure water or a high-pressure water jet is injected into the pressure relief hole by using a pump.

6. The tunnel rib control method according to claim 1, characterized in that: In step S3, the diameter of the pressure relief hole is 56 mm-200 mm, and the length of the pressure relief hole is 20 m-200 m.

7. The tunnel rib control method according to claim 1, characterized in that: In step S3, the number of the pressure relief holes is multiple, and the multiple pressure relief holes are arranged in multiple rows along the length direction of the lane, and each row includes a plurality of pressure relief holes arranged at intervals along the width direction of the lane.

8. The tunnel rib control method according to claim 1, characterized in that: In step S2, drilling, grouting, pre-tightening and other anchoring support operations are performed using integrated drilling and anchoring.

9. The tunnel rib control method according to claim 1, characterized in that: The composite material may be a silicate polyurea composite fiber material.

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