A composite anchoring method for water-rich surrounding rock using resin and microbial cement

Abstract

This invention relates to the field of underground engineering support technology, specifically disclosing a method for composite anchoring of resin and microbial cement in water-rich surrounding rock. The method includes: drilling anchor holes with a diameter larger than the anchor rod diameter in the surrounding rock of the tunnel to form an annular cavity, and pushing resin anchoring agent into the bottom of the anchor hole; injecting microbial self-healing cement slurry into the annular cavity to form a plastic slurry; inserting the anchor rod within a predetermined time after grouting and rotating and stirring it, causing the resin anchoring agent to solidify on the outer surface of the anchor rod to form a resin anchoring section, while simultaneously coating and mixing the plastic microbial cement slurry on the outside of the resin anchoring section to form a composite anchor body; finally, curing is performed to completely solidify the resin anchoring section, and the microbial cement slurry hardens to form a protective shell. This method, by constructing a coaxial composite structure of resin anchoring section and microbial cement protective shell, achieves a synergistic effect of rapid and immediate support for the surrounding rock and long-term impermeability, corrosion resistance, and dynamic self-healing, significantly improving the durability and stability of the anchoring system in water-rich environments.

Description

Technical Field

[0001] This invention relates to the field of underground engineering support technology, and in particular to a composite anchoring method for water-rich surrounding rock resin and microbial cement. Background Technology

[0002] Rock bolt support for roadways is one of the most commonly used active support methods in coal mines, metal mines, and various underground engineering projects. Resin anchors, in particular, are widely used in fully mechanized mining face roadways, rock tunnels, and chamber support due to their advantages such as rapid curing, high early strength, and simple construction process. Currently, projects often employ single resin anchors or combinations of resin anchors and cement mortar anchors, forming an integrated load-bearing system with the surrounding rock through anchor bolts and cables to improve the integrity and stability of the surrounding rock.

[0003] However, traditional anchoring systems face severe challenges in water-rich surrounding rock, especially under conditions of seepage (or gushing) water. Long-term immersion and scouring by groundwater accelerates the corrosion of anchor steel, causing cracks and pores within the resin or cement anchor body. The interfacial bond strength between the anchor body and the surrounding rock / anchor gradually weakens, significantly increasing the permeability of the anchoring zone. Particularly under mining disturbances or surrounding rock deformation, micro-cracks within the anchor body and surrounding rock mass continuously expand and connect, allowing groundwater to form stable seepage channels around the anchoring zone. This results in a continuous decrease in anchoring force, concentrated roadway deformation, and ultimately premature failure of the anchor support system.

[0004] Current common improvement measures (such as enhancing the corrosion resistance of anchor bolts and improving the water resistance of anchoring agents) mostly focus on improving the corrosion resistance or impermeability of individual materials. However, under long-term groundwater immersion conditions, these methods are difficult to effectively guarantee interfacial bonding performance and overall durability, and have limited ability to block seepage channels in the anchoring zone over the long term. In addition, existing anchoring systems are mostly "static" structures, lacking the ability to self-repair and re-seal newly formed cracks and seepage channels under the continuous action of groundwater.

[0005] Therefore, in order to address the problems of roadway deformation and support failure caused by anchor corrosion and interface deterioration under water-rich conditions, a new composite anchoring method of resin and microbial cement for water-rich surrounding rock is urgently needed. Summary of the Invention

[0006] The purpose of this invention is to provide a composite anchoring method for water-rich surrounding rock using resin and microbial cement. This method combines the rapid and high-strength anchoring performance of resin with the long-term impermeability and self-healing ability of cement-based materials. Furthermore, by optimizing the interface structure and construction process between the resin anchoring section and the outer cement shell, the overall corrosion resistance and long-term stability of the anchoring area in water-rich surrounding rock are improved.

[0007] To achieve the above objectives, the present invention provides the following solution: a method for composite anchoring of water-rich surrounding rock with resin and microbial cement, comprising:

[0008] S1. Drill anchor holes in the surrounding rock of the roadway. The diameter of the anchor holes is larger than the diameter of the anchor rod to be installed, so as to form an annular cavity between the anchor rod and the wall of the anchor hole; push the resin anchoring agent into the bottom of the anchor hole.

[0009] S2. Inject microbial self-healing cement slurry into the anchor hole to form a slurry in a plastic state; the microbial self-healing cement slurry contains cement-based materials, porous carrier particles, soluble calcium source and nutrients, and mineralized microorganisms in a spore state are fixed on the surface of the porous carrier particles.

[0010] S3. Within a predetermined time after grouting is completed in step S2, an anchor rod is inserted into the anchor hole, and the anchor rod is rotated and stirred to solidify the resin anchoring agent and form a resin anchoring section on the outer surface of the anchor rod. At the same time, the microbial self-healing cement slurry in a plastic state coats the outside of the resin anchoring section and mixes with it to form a composite anchor body. The resin anchoring agent contains coarse aggregate with a particle size of 1~3mm, so that the outer surface of the solidified resin anchoring section forms rough aggregate protrusions composed of partially exposed coarse aggregate.

[0011] S4. Perform curing to fully solidify the resin anchoring section, while the microbial self-healing cement grout hardens to form a microbial self-healing cement shell.

[0012] Optionally, in step S1, the radial thickness of the annular cavity is 8mm to 15mm.

[0013] Optionally, in step S2, the microbial self-healing cement grout is injected from the bottom of the anchor hole upwards through the grouting pipe, and the grouting pressure is 0.2~0.5MPa.

[0014] Optionally, in step S3, the predetermined time is 10 to 30 minutes after the microbial self-healing cement slurry is injected.

[0015] Optionally, in step S3, the length L1 of the resin anchoring section along the axial direction of the anchor hole is 0.5~1.5m.

[0016] Optionally, in step S3, by pre-fitting a sleeve with protrusions to the resin anchoring agent or by setting external ribs on the corresponding section of the anchor rod, annular or spiral ribs are formed on the outer surface of the cured resin anchoring section.

[0017] Optionally, by weight, the microbial self-healing cement slurry comprises: 100 parts cement, 10-40 parts mineral admixture, 5-30 parts porous carrier particles carrying spore-forming microorganisms, 5-30 parts soluble calcium source, 1-10 parts nutrient solution, and 40-80 parts water.

[0018] Optionally, the anchor rod is a hollow anchor rod with a lateral grout outlet, and the grouting step is carried out after the resin section is formed. First, the resin anchoring section is formed at the bottom of the anchor hole, and then microbial self-healing cement grout is injected into both ends of the anchoring section through the channel of the anchor rod.

[0019] Compared with the prior art, the present invention discloses at least the following beneficial effects:

[0020] This invention achieves the following technical effects by constructing a coaxial composite anchor body with an anchor bolt at its center, an inner resin anchoring section, and an outer microbial self-healing cement shell: the inner resin anchoring section, utilizing the rapid curing properties of resin, can form a high-strength anchor body within minutes of mixing, providing immediate and effective support for the surrounding rock; the outer microbial self-healing cement shell, with its dense cement matrix, provides long-term protection against groundwater seepage, protecting the anchor bolt and inner resin section from corrosion. Furthermore, the porous carrier particles pre-placed inside the shell, carrying microbial spores, can induce the formation of calcium carbonate precipitates upon contact with groundwater. It automatically seals the newly formed micro-cracks in the shell itself and at the interface with the surrounding rock, realizing dynamic self-repair of the seepage channels in the anchoring zone. At the same time, during the rotation and stirring process of the anchor bolt, the cement slurry in a plastic state fully interlocks with the macroscopic ribs and micro-aggregate protrusions formed on the outer surface of the resin section, forming a rough transition interface with mechanical locking function. This significantly enhances the shear bond strength and integrity between the resin section and the cement shell, thereby synergistically realizing the anchoring system's rapid support, long-term seepage resistance, corrosion resistance and continuous self-repair capability in water-rich surrounding rock environments, effectively improving the durability and stability of the support structure. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a flowchart of the composite anchoring method of water-rich surrounding rock resin and microbial cement according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of the composite anchor solid applicable to water-rich surrounding rock in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram showing the positional relationship between the anchor bolt, the resin anchoring section, and the microbial self-healing cement shell in an embodiment of the present invention;

[0025] Figure 4 This is a partially enlarged schematic diagram of the interface area between the resin anchoring section and the microbial self-healing cement shell in an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of the arrangement of composite anchor bodies in the surrounding rock of the tunnel in an embodiment of the present invention;

[0027] Figure 6 for Figure 5 A magnified view of a portion of the middle anchorage area A.

[0028] Figure reference numerals: 10, surrounding rock; 20, anchor hole; 30, anchor bolt; 40, resin anchoring section; 41, protruding rib; 42, aggregate protrusion; 50, microbial self-healing cement shell; 51, porous carrier particles; 70, seepage direction of sprinkling (gushing) water. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] The technical problem this invention aims to solve is that under long-term exposure to seepage (rushing) water, anchor bolts and their anchorage zones in the surrounding rock of roadways are prone to corrosion. The interfacial bond strength between the resin or cement anchor and the surrounding rock / anchor bolt continuously decreases, leading to a significant increase in the permeability of the anchorage zone. This, in turn, results in a continuous decrease in anchoring force, concentrated deformation of the surrounding rock, and premature failure of the support system. Existing single-resin anchors or resin-cement composite anchors are insufficient to simultaneously provide rapid support and long-term corrosion resistance, impermeability, and self-healing properties. They also lack the ability to permanently seal and repair newly formed fissures and seepage channels caused by groundwater.

[0031] Therefore, embodiments of the present invention provide a method and structure for composite anchoring of water-rich surrounding rock with resin and microbial cement. By constructing a coaxial composite anchor body with an inner resin anchoring section and an outer microbial self-healing cement shell in a single anchor hole, and optimizing the interface structure and construction time matching between the two, the anchoring system can achieve rapid molding, corrosion resistance, impermeability and long-term self-healing.

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Reference Figures 1 to 6 As shown in the figure, this embodiment provides a composite anchoring method for water-rich surrounding rock resin and microbial cement. This method comprehensively utilizes the rapid and high-strength anchoring characteristics of resin anchoring agents and the impermeability and long-term mineralization repair capabilities of microbial self-healing cement grout. It is used to improve the corrosion resistance and long-term stability of the surrounding rock anchoring support system in the environment of seepage (rushing) water. It is suitable for the surrounding rock anchoring support of coal mine roadways, metal mine roadways and other underground engineering projects with groundwater or seepage (rushing) water.

[0034] like Figure 1 As shown, the composite anchoring method for water-rich surrounding rock resin and microbial cement in this embodiment specifically includes the following steps:

[0035] Step S1: Drill holes and apply resin anchoring agent.

[0036] In the surrounding rock 10 of the roadway where water seeps in, anchor holes 20 are drilled according to the design support parameters (such as location, angle, and depth), and the pre-prepared resin anchoring agent is pushed into the bottom of the anchor holes 20.

[0037] In this embodiment, the diameter of the anchor hole 20 needs to be larger than the diameter of the anchor rod 30 to be installed, so as to form an annular cavity with a predetermined radial thickness between the anchor rod 30 and the wall of the anchor hole 20.

[0038] For example, in one specific embodiment, the diameter of the anchor rod 30 can be selected to be 22 mm, and the diameter of the anchor hole 20 can be 45 mm, thereby forming an annular cavity with a radial thickness of 11.5 mm.

[0039] After drilling is completed, the hole needs to be cleaned to create favorable conditions for subsequent grouting and anchoring. This step provides the spatial basis for the subsequent construction of the composite anchor body.

[0040] One or more sections of resin anchoring agent are pushed into the anchor hole 20 near the bottom of the hole. The total length of the resin anchoring section 40 is L1, which is 1.0m in this embodiment.

[0041] Step S2: Inject microbial self-healing cement grout.

[0042] The pre-prepared microbial self-healing cement grout is injected through the grouting pipe, starting from the bottom of the anchor hole 20 and proceeding upwards. In this embodiment, the grouting pressure should be controlled at 0.2~0.5MPa to ensure that the grout completely fills the annular cavity formed in step S1 and can moderately penetrate into the hole wall of the anchor hole 20 and the surrounding rock fissures 10. After grouting, a microbial self-healing cement grout in a plastic state, extending axially along the anchor hole 20, is formed in the annular cavity. After hardening, this grout will form a microbial self-healing cement shell 50 encasing the inner side. The matrix of the microbial self-healing cement shell 50 is a cement-based material, with porous carrier particles 51 uniformly distributed inside. The surface of the porous carrier particles 51 is fixed with mineralized microorganisms in a spore state and contains soluble calcium sources and nutrients.

[0043] Step S3: Install anchor bolts to form a composite anchor body.

[0044] While the self-healing microbial cement grout has not yet fully set and is still in a plastic state, the grouting pipe is removed and the anchor rod 30 is inserted.

[0045] Specifically, within 10 to 30 minutes after grouting is completed in step S2, when the microbial self-healing cement grout has not yet fully set and is in a plastic state, the grouting pipe is removed and the anchor rod 30 is inserted. The anchor rod 30 is driven to rotate and stir using a drilling rig, so that the resin anchoring agent is broken, mixed and quickly solidified, thereby forming a resin anchoring section 40 on the outer surface of the anchor rod 30.

[0046] During this mixing process, the plastic microbial self-healing cement grout is forcibly coated onto the outside of the forming resin anchoring section 40 and undergoes shear mixing with it. The resin anchoring section 40 reaches its load-bearing strength within minutes, achieving rapid initial support for the surrounding rock 10. At this point, a composite anchor body is initially formed within the anchor hole 20, centered on the anchor rod 30, with the inner layer being the resin anchoring section 40 and the outer layer being the plastic microbial cement grout.

[0047] like Figure 2 As shown, the composite anchor body described in this embodiment includes surrounding rock 10, anchor hole 20, anchor rod 30, resin anchoring section 40, and microbial self-healing cement shell 50.

[0048] In one specific embodiment, the anchor hole 20 is drilled in the surrounding rock 10 of the roadway where water seeps in (or surges in), and the surrounding rock 10 may be coal-bearing strata, sandstone, mudstone, or a combination thereof. The anchor rod 30 is arranged at the center of the anchor hole 20 and is typically made of threaded steel. The resin anchoring section 40 is fitted onto the outer surface of the anchor rod 30 and fixed to it, forming a high-strength anchor body arranged axially along the anchor rod 30. The microbial self-healing cement shell 50 fills the entire annular cavity between the anchor rod 30, the resin anchoring section 40, and the wall of the anchor hole 20, and is fixed to the wall of the anchor hole 20. In the cross-section of the anchor hole 20, the resin anchoring section 40 and the microbial self-healing cement shell 50 are coaxially arranged, with the resin anchoring section 40 located on the inner side and the microbial self-healing cement shell 50 on the outer side, together forming a composite anchor body within a single hole.

[0049] Based on the above embodiments, further, such as Figure 2 , Figure 3 and Figure 4 As shown, the anchor bolt 30 is placed at the center of the anchor hole 20, and the anchor bolt 30 is made of conventional left-hand threaded steel.

[0050] Based on the above embodiments, a resin anchoring section 40 is further provided around the anchor rod 30 at a deep position at the bottom of the hole. The resin anchoring section 40 is formed by curing a resin anchoring agent, and its axial length L1 along the anchor hole 20 is 0.5~1.5m, which is 1.0m in this embodiment. After curing, the resin anchoring section 40 wraps around the outer surface of the anchor rod 30, forming a high-strength anchor body with the anchor rod 30.

[0051] like Figure 4 As shown, the outer surface of the resin anchoring section 40 is formed with ribs 41 and rough aggregate protrusions 42; the ribs 41 are distributed circumferentially along the resin anchoring section 40, and can be continuous annular ribs 41 or spiral ribs 41 extending axially; the rough aggregate protrusions 42 are irregular protrusions formed by the partial exposure of coarse aggregate particles in the resin anchoring agent, partly embedded in the resin body and partly extending into the outer microbial cement shell.

[0052] The structure of the above-mentioned composite anchor body is as follows: Figures 3 to 5 As shown, Figure 3 A schematic diagram showing the positional relationship between the anchor bolt 30, the resin anchoring section 40, and the microbial self-healing cement shell 50 is shown. Figure 4 The mechanical interlocking structure formed by the annular or spiral ribs 41 and rough aggregate protrusions 42 on the outer surface of the resin anchoring section 40 and the outer microbial self-healing cement shell 50 is shown. Figure 5 The relative positional relationship of the anchorage zone and the groundwater seepage path are shown under the action of water saturation (rushing).

[0053] Step S4: Maintenance and Service.

[0054] After the installation of anchor bolt 30 is completed, curing is performed to ensure the complete solidification of the resin anchoring section 40. Simultaneously, the self-healing cement grout from plastic microorganisms hardens, ultimately forming a robust self-healing cement shell 50, thus completing the construction of the entire composite anchor body. During the subsequent long-term service of the roadway, when seepage water flows along the seepage direction 70 (e.g., Figure 5 When the microorganisms (in the direction indicated by the middle arrow) seep into the anchorage zone, the dormant mineralizing microorganisms in the self-healing cement shell 50 are activated, inducing the formation of carbonate mineral precipitates such as calcium carbonate. These precipitates can gradually fill and seal the newly formed microcracks and seepage channels at the interface between the shell and the surrounding rock 10, achieving dynamic self-repair of anchorage damage, thereby maintaining its low permeability and structural integrity for a long time.

[0055] Building upon the above embodiments, to further enhance the interfacial performance between the resin anchoring section 40 and the outer microbial self-healing cement shell 50, and to strengthen the overall integrity of the composite structure, this embodiment uses a specially formulated resin anchoring agent. Specifically, the resin anchoring agent used in this embodiment incorporates coarse aggregate particles (such as quartz sand) with a particle size of 1-3 mm. When the anchor rod 30 is rotated and stirred to solidify the resin and form the resin anchoring section 40, these coarse aggregate particles will be partially exposed at the outer edge of the resin, forming irregular aggregate protrusions 42. Simultaneously, by pre-fitting a thin-walled sleeve with annular or spiral protrusions onto the resin anchoring agent, or by pre-setting external ribs on the corresponding sections of the anchor rod 30, annular or spiral ribs 41 can be formed on the outer surface of the cured resin anchoring section 40.

[0056] Furthermore, the resin anchoring section 40 possesses a rough outer surface combining macroscopic and microscopic features, formed by ribs 41 and aggregate protrusions 42. During the mixing process in step S3, the plastic microbial cement slurry tightly coats this rough surface, embedding itself in the grooves of the ribs 41 and enveloping the aggregate protrusions 42. After the slurry hardens, a strong mechanical bond and a rough transition interface layer are formed between the resin anchoring section 40 and the microbial self-healing cement shell 50. This interface structure greatly enhances the shear bond strength between the two, effectively inhibits the initiation and development of annular microcracks at the interface, and fundamentally reduces interface permeability, thereby improving the sealing performance and long-term durability of the entire composite anchor.

[0057] In step S4, some groundwater enters the capillary pores inside the microbial self-healing cement shell 50 and the micro-cracks at the interface between the shell and the surrounding rock 10. The mineralizing microorganisms in the porous carrier particles 51 gradually recover under the influence of groundwater and a small amount of nutrients, inducing Ca2+ uptake. 2+ CO3 in the environment 2- / HCO3 -The reaction generates dense carbonate mineral precipitates in the shell and hole wall fissures, thereby gradually filling and sealing the newly formed fissures and seepage channels in the anchoring zone.

[0058] Based on the above embodiments, the composition of the microbial self-healing cement slurry may further include, by weight: 100 parts cement, 10-40 parts mineral admixtures (such as slag powder), 5-30 parts porous carrier particles carrying spore-forming microorganisms (such as diatomaceous earth particles), 5-30 parts soluble calcium source (such as calcium lactate), 1-10 parts nutrient solution (such as urea solution), and 40-80 parts water. By adjusting the admixtures, the initial setting and final setting times of the slurry can be controlled at 2-4 hours and 6-12 hours, respectively, to ensure sufficient plastic window period for step S3 construction and to achieve excellent interfacial shear mixing effect.

[0059] As another preferred embodiment of this method, the anchor bolt 30 can be a hollow anchor bolt. In this modified scheme, the order of construction steps can be adaptively adjusted: that is, step S1 can be performed first, followed by step S3, which uses resin anchoring agent to form a resin anchoring section 40 deep in the anchor hole 20; subsequently, through the hollow channel of the anchor bolt 30 itself, microbial self-healing cement grout is injected into the annular cavity outside the resin anchoring section 40 (equivalent to step S2), thereby forming a microbial self-healing cement shell 50. Although the grouting path and some process sequences are different from the aforementioned embodiments, the final composite anchor body constructed with the anchor bolt 30 as the center, the inner layer being the resin anchoring section 40, and the outer layer being the microbial self-healing cement shell 50, has the same core composition, spatial arrangement, optimized interface structure, and working principle of "rapid support + long-term self-healing". The hollow anchor bolt scheme provides greater flexibility for on-site construction and the possibility of subsequent maintenance and grouting.

[0060] It should be understood that the specific parameters in the above embodiments (such as aperture, rod diameter, grout ratio, construction time window, etc.) can be adjusted according to the actual engineering geological conditions, hydrological conditions and support design requirements. These reasonable changes based on the core concept of this invention should be included within the protection scope of this invention.

[0061] The embodiments of the present invention combine the rapid and high-strength characteristics of resin anchoring with the long-term impermeability and self-healing function of microbial cement shell, which can significantly improve the corrosion resistance and service life of the anchoring system in water-rich surrounding rock.

[0062] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0063] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method of composite anchoring of water-rich country rock resin with microbial cement, characterized in that, include: S1. Drill anchor holes (20) in the surrounding rock (10) of the roadway. The diameter of the anchor holes (20) is larger than the diameter of the anchor rod (30) to be installed, so as to form an annular cavity between the anchor rod (30) and the wall of the anchor hole (20); push the resin anchoring agent into the bottom of the anchor hole (20); S2. Inject microbial self-healing cement slurry into the anchor hole (20) to form a slurry in a plastic state; the microbial self-healing cement slurry contains cement-based materials, porous carrier particles (51), soluble calcium source and nutrients, and mineralized microorganisms in a spore state are fixed on the surface of the porous carrier particles (51). S3. Within a predetermined time after the grouting is completed in step S2, an anchor rod (30) is inserted into the anchor hole (20), and the anchor rod (30) is rotated and stirred to solidify the resin anchoring agent and form a resin anchoring section (40) on the outer surface of the anchor rod (30). At the same time, the microbial self-healing cement slurry in a plastic state is coated on the outside of the resin anchoring section (40) and mixed with it to form a composite anchoring body. The resin anchoring agent contains coarse aggregate with a particle size of 1~3mm, so that the outer surface of the solidified resin anchoring section (40) forms a rough aggregate protrusion (42) composed of the partial exposure of the coarse aggregate. S4. Perform curing to fully solidify the resin anchoring section (40), while the microbial self-healing cement slurry hardens to form a microbial self-healing cement shell (50).

2. The water-rich host rock resin and microbial cement composite anchoring method according to claim 1, characterized in that, In step S1, the radial thickness of the annular cavity is 8mm to 15mm.

3. The method for composite anchoring of water-rich surrounding rock resin and microbial cement according to claim 1, characterized in that, In step S2, the microbial self-healing cement grout is injected from bottom to top through the grouting pipe from the bottom of the anchor hole (20), and the grouting pressure is 0.2~0.5MPa.

4. The method for composite anchoring of water-rich surrounding rock resin and microbial cement according to claim 1, characterized in that, In step S3, the predetermined time is 10 to 30 minutes after the microbial self-healing cement slurry is injected.

5. The method for composite anchoring of water-rich surrounding rock resin and microbial cement according to claim 1, characterized in that, In step S3, the length L1 of the resin anchoring section (40) along the axial direction of the anchor hole (20) is 0.5~1.5m.

6. The method for composite anchoring of water-rich surrounding rock resin and microbial cement according to claim 1, characterized in that, In step S3, by pre-fitting a sleeve with protrusions on the resin anchoring agent or setting external ribs on the corresponding section of the anchor rod (30), annular or spiral protrusions (41) are formed on the outer surface of the cured resin anchoring section (40).

7. The method for composite anchoring of water-rich surrounding rock resin and microbial cement according to claim 1, characterized in that, By weight, the microbial self-healing cement slurry comprises: 100 parts cement, 10-40 parts mineral admixture, 5-30 parts porous carrier particles (51) carrying spore-forming microorganisms, 5-30 parts soluble calcium source, 1-10 parts nutrient solution, and 40-80 parts water.

Images