Grouting construction method for glass fiber anchor rod of tunnel with extra-large cross section

Abstract

The invention discloses a grouting construction method for a glass fiber anchor rod of an extra-large-section tunnel, which comprises the following steps of: drilling in the section tunnel to drill a mounting hole for mounting the glass fiber anchor rod, performing rotary jet grouting on the inner wall of the mounting hole, and injecting a resin anchoring agent along the inner wall of the mounting hole, the depth filling rate eta of the resin anchoring agent in the mounting hole meets the relational expression: eta = k (D1-D2) 2 / D12, and k is a correction coefficient considering the depth of the resin anchoring agent; d1 is the diameter of the drill hole, and D2 is the diameter of the glass fiber anchor rod. By means of the grouting construction method, the gap between the mounting hole and the glass fiber anchor rod can be effectively filled, the binding force between the glass fiber anchor rod and surrounding rock mass is enhanced, rotary spraying treatment is conducted on the inner wall of the mounting hole, friction resistance of the glass fiber anchor rod in the drilling process can be reduced, and the surface damage risk caused by friction is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, and more specifically to a grouting construction method for a glass fiber anchor rod in a tunnel with an extra-large cross-section. Background Art

[0002] Anchor rods are widely used in tunnel construction and geotechnical engineering. They can combine surrounding rock with stable rock mass to produce suspension effect, composite beam effect and reinforcement effect to achieve the purpose of support. Generally speaking, metal anchor rods are often used for support in engineering, mainly steel. However, due to their heavy weight, steel anchor rods may encounter greater difficulties during installation. For example, after concrete pouring, steel anchor rods may tilt or offset, resulting in the inability to align the installation hole with the steel anchor rod, thereby increasing the difficulty of installation. In addition, during the construction process, due to its material properties, such as high strength and rigidity, although steel anchor rods can provide good support effects, their construction efficiency is relatively low. These factors make steel anchor rods have certain limitations in certain specific environments. Therefore, non-metallic anchor rods, such as fiberglass anchor rods, are often used for support in specific projects.

[0003] Fiberglass anchors, also known as basalt fiber anchors, have broad application prospects due to their high strength, light weight, and ability to be cut mechanically during the construction of underground structures.

[0004] However, for the New Austrian Tunnel Construction Method (also known as the New Austrian Tunnel Construction Method, which is a construction method based on tunnel engineering experience and rock mechanics theory, combining anchor rods and shotcrete as the main support means), during the anchor rod construction work carried out in the initial support stage, it was found that the anchor rods had the following deficiencies:

[0005] (1) Compared with steel bar materials, the plasticity of glass fiber anchor rods is not high, and it is easy to break during construction, which increases the difficulty of construction. Secondly, glass fiber anchor rods are easily damaged due to friction during drilling;

[0006] (2) Fiberglass anchors lack sufficient shear strength. The quality of fiberglass anchors is usually measured within 10% of the longitudinal strength. During the production of anchors and clamps, they need to be made according to the shear strength of the fiberglass anchors. Otherwise, the shear strength and tensile properties will be affected, which increases the difficulty and cost of making anchors and clamps.

[0007] (3) Compared with metal fiberglass anchors, another important defect of fiberglass anchors is their poor welding performance. Due to the high support strength required for large-section tunnels, a large number of fiberglass anchors are used in the initial tunnel support, and the construction time is long. The fiberglass anchor slurry must be fastened to the end of the fiberglass anchor before it completely penetrates the soil and solidifies. Due to the poor welding performance of fiberglass anchors, it is difficult to weld anchor fasteners like traditional metal fiberglass anchors. Secondly, fiberglass anchors are prone to damage due to friction during the fastener construction process. Summary of the invention

[0008] In order to overcome the deficiencies of the prior art, the present invention provides a grouting construction method for a glass fiber anchor rod in a tunnel with an extra-large cross-section, so as to solve the problem that the surface of the glass fiber rod is easily damaged due to friction during the drilling process.

[0009] The technical solution of the present invention is as follows: A grouting construction method for a glass fiber anchor rod in a large-section tunnel, wherein a hole is drilled in the section tunnel to drill a mounting hole for mounting the glass fiber anchor rod, the inner wall of the mounting hole is subjected to a rotary spraying treatment, and then a resin anchoring agent is injected along the inner wall of the mounting hole, and the depth filling rate η of the resin anchoring agent in the mounting hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction factor considering the penetration of resin anchor; D1 is the borehole diameter, and D2 is the glass fiber anchor diameter.

[0010] Further, the following steps are included:

[0011] S1. Drilling holes on the tunnel face at a predetermined depth and direction to drill installation holes for installing glass fiber anchor rods;

[0012] S2. Inject resin anchor along the inner wall of the mounting hole. The depth filling rate η of the resin anchor in the mounting hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction factor considering the penetration of resin anchor; D1 is the borehole diameter, and D2 is the glass fiber anchor diameter.

[0013] S3. Slip the porous pad onto the anchor head at the end of the fiberglass anchor rod so that the porous pad is in full contact with the surrounding rock. Then install the nut on the threaded portion of the fiberglass anchor rod and tighten it to press the pad against the surrounding rock. The nut interacts with the thread of the fiberglass anchor rod through its thread to generate a clamping force to ensure close contact and stable connection between the pad and the surrounding rock.

[0014] S4. Two adjacent fiberglass anchor rods are fixed by fasteners.

[0015] Further, in step S1, drilling is performed on the tunnel face at a predetermined depth and direction to drill out installation holes for installing glass fiber anchor rods, which specifically includes the following steps:

[0016] S11. Mark the hole position before drilling, and the hole position deviation should be less than 100mm;

[0017] S12. When drilling, the boom of the drill rig is pressed tightly against the palm face. In the initial stage of drilling, the rotation speed of the drill bit is controlled at 50r / min-60r / min, and the feed speed of the drill bit is controlled at 5mm / rev-10mm / rev. After the drilling depth reaches 20cm, the rotation speed and feed speed are increased to 100r / min-200r / min, and the feed speed of the drill bit is increased to 10mm / rev-20mm / rev.

[0018] S13. After drilling is completed, clean the rock powder and impurities in the hole.

[0019] Furthermore, before drilling, a concrete layer with a thickness of 5 cm to 10 cm is sprayed on the working surface for sealing before drilling.

[0020] Furthermore, before injecting the resin anchor, a drilling rig is used to drill a grouting pipe with a nozzle into a predetermined position of the installation hole, and the slurry is sprayed out from the nozzle in a high-pressure jet through high-pressure equipment to punch and fill the inner wall of the installation hole, so that a reinforcement layer is formed on the hole wall of the installation hole.

[0021] Furthermore, the diameter D1 of the mounting hole and the diameter D2 of the rod body of the glass fiber anchor rod satisfy the relationship: D1-D2≥20 mm.

[0022] Furthermore, the length of the rod body of the glass fiber anchor rod inserted into the mounting hole is not less than 95% of the length of the mounting hole.

[0023] Furthermore, the fiberglass anchor rods are arranged in a 1.2m×1.2m plum blossom pattern.

[0024] Furthermore, in step S2, a resin anchor is injected along the inner wall of the installation hole. Specifically, the resin anchor is injected into the installation hole through a grouting pump. During the grouting process, the grouting pressure gradually increases. The initial grouting pressure is 0.5MPa to 1.0MPa. The grouting pressure gradually increases to 1.2MPa and lasts for more than 10 minutes.

[0025] Furthermore, the filling amount of the resin anchoring agent is 50% to 70% of the effective anchoring length of the glass fiber anchor rod.

[0026] According to the above scheme, the beneficial effect of the present invention is that: the present invention provides a grouting construction method for a glass fiber anchor rod in a large-section tunnel, drilling is performed in the section tunnel to drill out a mounting hole for installing the glass fiber anchor rod, the inner wall of the mounting hole is subjected to a rotary spraying treatment, and then a resin anchoring agent is injected along the inner wall of the mounting hole, and the depth filling rate η of the resin anchoring agent in the mounting hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction factor considering the depth of the resin anchor; D1 is the borehole diameter, and D2 is the diameter of the fiberglass anchor. Through this grouting construction method, the gap between the installation hole and the fiberglass anchor can be effectively filled, and the bonding force between the fiberglass anchor and the surrounding rock mass can be enhanced, thereby protecting the fiberglass anchor from erosion by the external environment and improving its durability. Secondly, by performing rotary spraying treatment on the inner wall of the installation hole, the friction resistance of the fiberglass anchor during drilling can be reduced, and the risk of surface damage caused by friction can be reduced. At the same time, the filling of the resin anchor can further reduce the direct contact between the fiberglass anchor and the hole wall, thereby reducing wear. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a schematic flow chart of a grouting construction method of a glass fiber anchor rod for a tunnel with a particularly large cross section according to an embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of the construction process of glass fiber anchor rods;

[0030] Figure 3 Schematic diagram of the structure of the glass fiber anchor rod in an embodiment of the present invention.

[0031] In the figure, 1. rod body; 2. porous pad; 3. nut. DETAILED DESCRIPTION

[0032] The following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention, that is, the present invention is not limited to the described embodiments.

[0033] In order to better understand the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0034] In a preferred embodiment of the present invention, a grouting construction method for glass fiber anchor rods in large-section tunnels is provided, the core purpose of which is to overcome the low bending strength and poor welding performance of glass fiber anchor rods, and to ensure that the glass fiber anchor rods can give full play to their mechanical properties through a specific construction process, thereby achieving a good anchoring effect. Specifically, drilling is performed in the cross-section tunnel to drill out a mounting hole for installing the glass fiber anchor rod, the inner wall of the mounting hole is subjected to a rotary spraying treatment, and then a resin anchoring agent is injected along the inner wall of the mounting hole, and the depth filling rate η of the resin anchoring agent in the mounting hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction coefficient considering the depth of the resin anchor, and the value of k is 0.5-0.8; D1 is the borehole diameter, and D2 is the diameter of the glass fiber anchor rod. With this design, the optimal depth filling rate of the resin anchor can be quickly calculated through the mathematical model, which can not only improve the controllability of the filling depth, but also improve the construction efficiency, thereby optimizing the anchoring effect, ensuring the installation firmness and stability of the overall structure, and thus ensuring construction safety.

[0035] In this embodiment, if the depth filling rate η of the resin anchor in the mounting hole is insufficient, it may easily lead to insufficient anchoring force; and if the filling depth is too large, it may cause material waste and unnecessary cost increase.

[0036] In this embodiment, the diameter of the drill hole (D1) is determined according to the design requirements and the diameter of the fiberglass anchor rod (D2) to ensure that there is enough space for grouting. Specifically, the diameter of the drill hole (D1) is greater than the diameter of the fiberglass anchor rod body by more than 20 mm. This parameter setting ensures that there is enough space around the fiberglass anchor rod for grouting. The grouting material (such as cement slurry or resin) can fill the gap between the fiberglass anchor rod and the hole wall to form a good bond, improve the anchoring force, and help ensure the stability and bearing capacity of the fiberglass anchor rod. At the same time, it also provides a certain adaptability to the irregularity of the hole wall; secondly, this design allows the fiberglass anchor rod to be inserted freely, reducing friction and damage risks during installation, and ensuring that the fiberglass anchor rod can be smoothly inserted to the designed depth, which helps to improve construction efficiency, reduce material loss, and ensure the correct positioning of the fiberglass anchor rod. In this embodiment, the length of the fiberglass anchor rod body inserted into the hole is not less than 95%, and the over-depth is less than 50 mm. This design ensures that most of the length of the fiberglass anchor can be in contact with the surrounding rock, which can maximize the anchoring effect of the fiberglass anchor and improve the stability of the initial support of the tunnel. Secondly, the over-depth is limited to within 50mm to avoid additional costs and material waste caused by excessive drilling. At the same time, it also avoids the instability of the surrounding rock that may be caused by excessive drilling.

[0037] It is worth mentioning that in this embodiment, before drilling, a concrete layer with a thickness of 5 to 10 cm is sprayed on the working surface for pre-drilling sealing treatment. Spraying a concrete layer with a thickness of 5 to 10 cm on the working surface can effectively reinforce the working surface, fill and solidify the tiny cracks and gaps on the working surface, and reduce the risk of collapse that may occur during the drilling process. Secondly, the concrete layer with a thickness of 5 to 10 cm can be used as a guide layer to help the drilling equipment to accurately operate along the predetermined trajectory, reduce deviations, and thus improve the accuracy and efficiency of drilling. In this embodiment, if the concrete layer is too thin, that is, the thickness of the concrete layer is less than 5 cm, it is difficult to effectively reinforce the working surface, and it is easy to collapse and other safety problems during the drilling process; if the concrete layer is too thick, that is, the thickness of the concrete layer is greater than 10 cm, the amount of concrete material used will increase, which will increase the cost of the project. Secondly, the overly thick concrete layer increases the penetration difficulty of the drilling equipment and reduces the drilling efficiency. In the subsequent processing process, additional steps are required to remove the excess concrete layer, which increases the complexity and cost of the project.

[0038] In this embodiment, the inner wall of the installation hole is cleaned and reinforced by high-pressure rotary spraying technology to improve the roughness and adhesion of the inner wall, providing a good foundation for the subsequent injection of resin anchoring agent. Specifically, a drilling rig is used to drill a grouting pipe with a nozzle into a predetermined position of the installation hole, and the slurry is sprayed out from the nozzle in a high-pressure jet through high-pressure equipment to punch and fill the inner wall of the installation hole. When the drill rod is gradually lifted at a certain speed, the mixed slurry is forced to be stirred and consolidated with the soil particles synchronously with the lifting of the drill rod, thereby forming a reinforcement layer on the wall of the installation hole.

[0039] For further explanation, the embodiment provides a grouting construction method for a glass fiber anchor rod in a tunnel with a large cross section based on the above scheme, which specifically includes the following steps:

[0040] S1. Drilling holes on the tunnel face at a predetermined depth and direction to drill installation holes for installing glass fiber anchor rods;

[0041] Specifically, the above step S1 specifically includes the following steps:

[0042] S11. Before drilling, the surveyor shall mark the hole position, and the hole position deviation shall be less than 100mm;

[0043] S12. When drilling, the rig boom is pressed tightly against the palm face to prevent excessive vibration and improve drilling accuracy. In the early stage of drilling, the rotation speed of the drill bit is controlled at 50-60r / min (revolutions per minute), and the feed speed of the drill bit is controlled at 5-10mm / rev (millimeter per revolution). After drilling 20cm deep, the normal drilling speed is switched to. At this time, the rotation speed and feed speed are increased so that the rotation speed of the drill bit can be increased to 100-200r / min, and the feed speed of the drill bit can be increased to 10-20mm / rev, so as to improve the drilling efficiency and adapt to hard rock or relatively stable rock formations.

[0044] S13. After drilling is completed, clean the rock powder and impurities in the hole.

[0045] S2. Inject resin anchor along the inner wall of the mounting hole. The depth filling rate η of the resin anchor in the mounting hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction factor considering the penetration of resin anchoring agent, and the value of k is 0.5-0.8; D1 is the borehole diameter, and D2 is the diameter of the glass fiber anchor rod;

[0046] S3. Slip the porous pad onto the anchor head at the end of the fiberglass anchor rod so that the porous pad is in full contact with the surrounding rock. Then install the nut on the threaded portion of the fiberglass anchor rod and tighten it to press the pad against the surrounding rock. The nut interacts with the thread of the fiberglass anchor rod through its thread to generate a clamping force to ensure close contact and stable connection between the pad and the surrounding rock.

[0047] S4. Two adjacent fiberglass anchor rods are fixed by fasteners.

[0048] In step S1, drilling is performed on the tunnel face according to a predetermined depth and direction to drill installation holes for installing glass fiber anchor rods, which specifically includes the following steps:

[0049] S11. Mark the hole position before drilling, and the hole position deviation should be less than 100mm;

[0050] Specifically, in the construction of extra-large cross-section tunnels, accurate marking of the hole positions before drilling and controlling the hole position deviation within a range of less than 100mm can ensure the accuracy of the drilling, thereby providing accurate positioning for the subsequent glass fiber anchor installation and grouting construction, which helps to improve the construction quality of the entire tunnel support structure; secondly, when constructing in limited spaces such as tunnels, excessive drilling deviation may cause damage to surrounding structures. Controlling the hole position deviation within 100mm can protect the safety of surrounding structures, thereby reducing correction work, shortening construction time, and improving overall construction efficiency.

[0051] S12. When drilling, the boom of the drill rig is pressed tightly against the palm face. In the initial stage of drilling, the rotation speed of the drill bit is controlled at 50r / min-60r / min, and the feed speed of the drill bit is controlled at 5mm / rev-10mm / rev. After the drilling depth reaches 20cm, the rotation speed and feed speed are increased to 100r / min-200r / min, and the feed speed of the drill bit is increased to 10mm / rev-20mm / rev.

[0052] Specifically, the drill bit rotation speed is controlled at 50r / min to 60r / min, which helps reduce the wear of the drill bit during initial drilling, and can control the drilling direction in the early stage of drilling to avoid excessive drilling deviation. The feed speed is controlled at 5mm / rev to 10mm / rev to ensure that the drill bit will not be damaged or cause drilling deviation due to excessive advancement, and it can also reduce the friction between the drill bit and the rock to avoid overheating of the drill bit.

[0053] S13. After drilling is completed, clean the rock powder and impurities in the hole.

[0054] In this embodiment, before drilling, a concrete layer with a thickness of 5 cm to 10 cm is sprayed on the working surface for pre-drilling sealing treatment, thereby forming a protective layer on the working surface, which can significantly enhance the overall stability of the working surface and prevent safety hazards caused by vibration or collapse during the drilling process. It is worth mentioning that the thickness of the concrete layer is 5 cm to 10 cm. Such a design will neither cause the concrete layer to be too thick to increase construction costs and time, nor cause the concrete layer to be too thin to play an effective sealing and protective role.

[0055] In this embodiment, before injecting the resin anchor, a drilling rig is used to drill a grouting pipe with a nozzle into a predetermined position of the installation hole, and the slurry is sprayed out from the nozzle in a high-pressure jet through high-pressure equipment to punch and fill the inner wall of the installation hole, thereby forming a reinforcement layer on the wall of the installation hole.

[0056] In this embodiment, the diameter D1 of the mounting hole and the rod diameter D2 of the fiberglass anchor satisfy the relationship: D1-D2≥20mm. This design allows the diameter D1 of the mounting hole to be at least 20mm larger than the rod diameter D2 of the fiberglass anchor, ensuring that the fiberglass anchor can be easily and smoothly inserted into the mounting hole, reducing friction resistance during installation, and avoiding installation difficulties or damage to the fiberglass anchor due to size mismatch. Secondly, this design allows the gap between the mounting hole and the fiberglass anchor to provide sufficient space for the resin anchor, so that the resin anchor can fully fill the gap between the hole wall and the fiberglass anchor to form a strong bonding layer, thereby improving the anchoring force and stability of the fiberglass anchor.

[0057] In this embodiment, the length of the rod body of the glass fiber anchor rod inserted into the mounting hole is not less than 95% of the length of the mounting hole.

[0058] In this embodiment, the fiberglass anchor rods are arranged in a 1.2m×1.2m plum blossom pattern. Specifically, in the horizontal direction, the distance between adjacent fiberglass anchor rods is 1.2 meters; in the vertical direction, the distance between upper and lower adjacent fiberglass anchor rods is also 1.2 meters. This design ensures that the supporting force between the fiberglass anchor rods can be evenly distributed to achieve the expected reinforcement effect.

[0059] In this embodiment, in step S2, the resin anchor is injected along the inner wall of the installation hole, specifically: the resin anchor is injected into the installation hole through a grouting pump, and the grouting pressure gradually increases during the grouting process. The initial grouting pressure is 0.5MPa~1.0MPa, and the grouting pressure gradually increases to 1.2MPa and lasts for more than 10 minutes.

[0060] In this embodiment, the filling amount of the resin anchoring agent is 50% to 70% of the effective anchoring length of the glass fiber anchor rod.

[0061] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

[0062] The above is an exemplary description of the present invention in conjunction with the accompanying drawings. It is obvious that the implementation of the present invention is not limited to the above-mentioned method. As long as various improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A grouting construction method for glass fiber anchor rods in extra-large cross-section tunnels, characterized in that: Drilling is performed in the cross-section tunnel to drill out the installation hole for installing the glass fiber anchor rod, the inner wall of the installation hole is subjected to rotary spraying, and then the resin anchoring agent is injected along the inner wall of the installation hole. The depth filling rate η of the resin anchoring agent in the installation hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction factor considering the penetration of resin anchor; D1 is the borehole diameter, and D2 is the glass fiber anchor diameter.

2. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 1, characterized in that: The following steps are involved: S1. Drilling holes on the tunnel face at a predetermined depth and direction to drill installation holes for installing glass fiber anchor rods; S2. Inject resin anchor along the inner wall of the mounting hole. The depth filling rate η of the resin anchor in the mounting hole satisfies the relationship: η=k(D1-D2) 2 / D1 2 , where k is the correction factor considering the penetration of resin anchoring agent, and the value of k is 0.5-0.8; D1 is the borehole diameter, and D2 is the diameter of the glass fiber anchor rod; S3, putting the porous pad onto the anchor head at the end of the fiberglass anchor, then installing the nut on the threaded portion of the fiberglass anchor, and tightening it to press the pad tightly against the surrounding rock; S4. Two adjacent fiberglass anchor rods are fixed by fasteners.

3. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 2, characterized in that: In step S1, drilling is performed on the tunnel face according to a predetermined depth and direction to drill installation holes for installing glass fiber anchor rods, which specifically includes the following steps: S11. Mark the hole position before drilling, and the hole position deviation should be less than 100mm; S12. When drilling, the boom of the drill rig is pressed tightly against the palm face. In the initial stage of drilling, the rotation speed of the drill bit is controlled at 50r / min-60r / min, and the feed speed of the drill bit is controlled at 5mm / rev-10mm / rev. After the drilling depth reaches 20cm, the rotation speed and feed speed are increased to 100r / min-200r / min, and the feed speed of the drill bit is increased to 10mm / rev-20mm / rev. S13. After drilling is completed, clean the rock powder and impurities in the hole.

4. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 1, characterized in that: Before drilling, a concrete layer with a thickness of 5cm to 10cm is sprayed on the working surface for sealing before drilling.

5. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 2, characterized in that: Before injecting the resin anchor, use a drill to drill a grouting pipe with a nozzle into the predetermined position of the installation hole, and use high-pressure equipment to spray the slurry out from the nozzle in a high-pressure jet to punch and fill the inner wall of the installation hole, so that a reinforcement layer is formed on the hole wall of the installation hole.

6. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 1, characterized in that: The diameter D1 of the mounting hole and the diameter D2 of the glass fiber anchor rod satisfy the relationship: D1-D2≥20mm.

7. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 1, characterized in that: The length of the rod body of the fiberglass anchor rod inserted into the mounting hole is not less than 95% of the length of the mounting hole.

8. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 1, characterized in that: The fiberglass anchor rods are arranged in a 1.2m×1.2m plum blossom shape.

9. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 2, characterized in that: In step S2, a resin anchor is injected along the inner wall of the installation hole. Specifically, the resin anchor is injected into the installation hole through a grouting pump. During the grouting process, the grouting pressure gradually increases. The initial grouting pressure is 0.5MPa to 1.0MPa. The grouting pressure gradually increases to 1.2MPa and lasts for more than 10 minutes.

10. The grouting construction method of a glass fiber anchor rod for a large-section tunnel as claimed in claim 1, characterized in that: The filling amount of the resin anchoring agent is 50% to 70% of the effective anchoring length of the glass fiber anchor rod.

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