Hydraulic expansion anchor rod suitable for surrounding fractured rock mass and its usage method

Abstract

This application discloses a hydraulic expansion anchor rod suitable for surrounding crushed rock mass and its method of use, The anchor rod includes a body and a water injection bag, and one end of the body is disposed around the borehole. The anchor rod is stretched and fixed to the surrounding crushed rock body to form an anchor fixing segment; The other end of the body is a free end and extends from the surrounding crushed rock mass, and is subjected to tensile stress. The water injection bag is attached to the anchor rod body, and The water injection bag is in close contact with the anchor rod body after water injection. The anchor rod body extends in the axial and radial directions and fixes the anchor. Axial pressing force is applied to the segment and the free end, and the surrounding crushed rock mass around the water injection bag is pressed against the segment and the free end. A radial pressing force is applied to the borehole to ensure sufficient contact, and three-directional stress is applied to the surrounding crushed rock around the borehole. The present application provides a water injection bag that expands by injecting water, thereby consolidating the surrounding crushed rock mass. This increases the integrity of the surrounding fractured rock mass and the friction between the anchor rod structure and the surrounding fractured rock mass. .

Description

Technical Field

[0001] This application relates to the technical field of rock and soil anchor fixing, and specifically to a hydraulic expansion anchor suitable for surrounding fractured rock mass and its usage method.

Background Art

[0002] In the construction of rock mass projects, construction safety accidents often occur in the surrounding fractured rock mass. According to on-site practical experience , in order to ensure the safety of construction, appropriate support and protection measures are the most effective means to ensure the stability of the rock mass in the surrounding fractured zone. The support and protection measures by anchor rods are widely applied to the construction of rock mass projects as a convenient, economical and effective means. However, the existing anchor rod structure does not have a very ideal support effect in the rock mass of the surrounding fractured zone , cracks and large gaps occur in the fractured rock mass, and the damage to the anchor slurry is also large. Therefore, the anchor fixing effect between one side and the surrounding fractured rock mass is poor, the frictional force between the rock mass within the anchor fixing area and the anchor itself is very small, and it is difficult for the anchor rod to achieve the expected effect in the fractured rock mass . Therefore, the existing anchor rod structure cannot meet the support and protection requirements of the surrounding fractured zone in rock mass projects.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The embodiments of this application provide a hydraulic expansion anchor rod suitable for surrounding fractured rock mass and its usage method to solve the problem that the existing anchor rod structure in the surrounding fractured rock mass in geotechnical engineering cannot meet the support and protection requirements of the project. The technical solutions are as follows

Means for Solving the Problems

[0004] The first aspect of the present application provides a hydraulic expansion anchor rod suitable for surrounding fractured rock masses, including an anchor rod body and a water injection bag. One end of the anchor rod body extends and is fixed to the surrounding fractured rock mass around the excavation hole to form an anchor fixing segment. The other end of the anchor rod body is a free end and extends out of the surrounding fractured rock mass, and the surrounding fractured rock mass is fixed by applying tensile stress. The water injection bag is mounted on the anchor rod body and is in close contact with the anchor rod body. The water injection bag is located between the anchor fixing segment and the free end. Among them, after the water injection bag is filled with water, it expands along the axial direction and the radial direction of the anchor rod body respectively, and applies an axial pressing force to the anchor fixing segment and the free end respectively, and applies a radial pressing force to the surrounding fractured rock mass around the water injection bag to make sufficient contact, providing triaxial stress to the surrounding fractured rock mass around the excavation hole. For example, in the hydraulic expansion anchor rod suitable for surrounding fractured rock masses provided by one embodiment, the water injection bag is provided with a telescopic folding belt along the axial direction of the anchor rod body, and the water injection bag expands along the axial direction of the anchor rod body after being filled with water through the telescopic folding belt. For example, in the hydraulic expansion anchor rod suitable for surrounding fractured rock masses provided by one embodiment, a water injection pipe is provided at the end of the water injection bag facing the free end, and the water injection pipe extends out of the surrounding fractured rock mass.

[0005]

[0006]

[0007] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment a lateral anchor tray is provided at the free end of the anchor rod body, and a tensile stress is applied to the anchor rod body through the said external anchor tray.

[0008] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment the water injection pipe penetrates through the external anchor tray and extends out from the external anchor tray, so that after the external anchor tray applies a tensile stress to the anchor rod body, water is injected into the water injection bag through the water injection pipe.

[0009] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment a rust prevention layer is applied to the outer wall surface where the anchor rod body contacts the water injection bag.

[0010] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment two expansion and contraction folding belts are provided at intervals along the axial direction of the anchor rod body on the water injection bag, and one of the expansion and contraction folding belts expands towards the free end after water injection, and the other said expansion and contraction folding belt expands towards the anchor fixing segment after water injection.

[0011] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment after water injection, the water injection bag expands in the axial direction of the anchor rod body through the two expansion and contraction folding belts, and both ends of the water injection bag abut against the anchor fixing segment and the said external anchor tray respectively, and apply an axial pressing force to the anchor fixing segment and the external anchor tray. ​

[0012] The second aspect of the present application provides a method for using the hydraulic expansion anchor rod suitable for surrounding fractured rock masses, including the following steps: S1 Insert and fix the head of the anchor fixing segment of the anchor rod body into the excavation hole; S2 Apply stress to the anchor rod body by tension with an external anchor tray; S3 Inject water into the water injection bag through a water injection pipe, expand the water injection bag with folds, expand the water injection bag radially around the anchor rod body, fully contact the surrounding fractured rock mass around the water injection bag to apply a radial pressing force, and expand the telescopic fold belt on the water injection bag to expand the anchor rod body axially, and apply an axial pressing force to the anchor fixing segment and the external anchor tray.

Advantages of the Invention

[0013]

[0014] ​​​​​​​​​​​​​​​​To more clearly explain the technical solutions in the embodiments or the background art of this specification, The following briefly describes the drawings that need to be used in the embodiments. Of course, the drawings in the following description are only some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without creative efforts.

[0015] Figure 1 is a schematic structural diagram of the un-injected state of the hydraulic expansion anchor rod of this application.

[0016] Figure 2 is a schematic cross-sectional view of the un-injected state of the hydraulic expansion anchor rod of this application.

[0017] Figure 3 is a schematic structural diagram of the injected state of the hydraulic expansion anchor rod of this application.

[0018] Figure 4 is a schematic cross-sectional view of the injected state of the hydraulic expansion anchor rod of this application.

Modes for Carrying Out the Invention

[0019] The following combines the drawings of the embodiments of this application to clearly and completely explain the technical solutions of the embodiments of this application. Of course, the embodiments described here are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative efforts

[0020] Unless otherwise defined, the technical terms or scientific terms used in this application have the ordinary meanings understood by those with ordinary skills in the field to which this application belongs. The "first", "second" and similar terms used in this application do not represent order, number, or importance, but are used to distinguish different components. Terms such as "comprised of" or "including" The term "including" means that the elements or objects described before the term cover the elements or objects listed after the term and equivalents thereof without excluding other elements or objects. Similar terms such as "connected" or "communicating" do not refer only to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper", "lower", "left", "right", etc. are used only to represent relative positional relationships, and if the absolute position of the object being described changes, the relative positional relationship may change accordingly. It is intended to cover the elements or objects listed after the term and equivalents thereof without excluding other elements or objects. Similar terms such as "connected" or "communicating" do not refer only to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper", "lower", "left", "right", etc. are used only to represent relative positional relationships, and if the absolute position of the object being described changes, the relative positional relationship may change accordingly. not limited to physical or mechanical connections, and can include electrical connections, whether direct or indirect. Terms such as "upper", "lower" ", "left", "right", etc. are used only to represent relative positional relationships, and if the absolute position of the object being described changes, the relative positional relationship may change accordingly. "left", "right", etc. are used only to represent relative positional relationships, and if the absolute position of the object being described changes, the relative positional relationship may change accordingly.

[0021] As shown in FIGS. 1-4, the first aspect of the present application provides a hydraulic expansion anchor rod suitable for surrounding fractured rock masses, including an anchor rod body 10 and a water injection bag 20. One end of the anchor rod body 10 extends and is fixed to the surrounding fractured rock mass 30 around the excavation hole to form an anchor fixing segment 11. The other end of the anchor rod body 10 is a free end 12, and extends out of the surrounding fractured rock mass 30, and the surrounding fractured rock mass 30 is fixed by applying a tensile stress. The water injection bag 20 is mounted on the anchor rod body 10 and is in close contact with the anchor rod body 10, and the water injection 20 bag is between the anchor fixing segment 11 and the free end 12. Among them, after the water injection bag 20 is filled with water, it expands along the axial direction and the radial direction of the anchor rod body 10 respectively, and applies an axial pressing force to the anchor fixing segment 11 and the free end 12 respectively, and applies a radial pressing force to the surrounding fractured rock mass 30 around the water injection bag 20 to make sufficient contact, and provides triaxial stress to the surrounding fractured rock mass 30 around the excavation hole. One end of the anchor rod body 10 extends and is fixed to the surrounding fractured rock mass 30 around the excavation hole to form an anchor fixing segment 11, and the other end of the anchor rod body 10 is a free end 12, which extends out of the surrounding fractured rock mass 30 and fixes the surrounding fractured rock mass 30 by applying a tensile stress. The water injection bag 20 is mounted on the anchor rod body 10 and is in close contact with the anchor rod body 10, and the water injection 20 bag is between the anchor fixing segment 11 and the free end 12. 20 is mounted on the anchor rod body 10 and is in close contact with the anchor rod body 10, and the water injection 20 bag is between the anchor fixing segment 11 and the free end 12. Among them, after the water injection bag 20 is filled with water, it expands along the axial direction and the radial direction of the anchor rod body 10 respectively, and applies an axial pressing force to the anchor fixing segment 11 and the free end 12 respectively, and applies a radial pressing force to the surrounding fractured rock mass 30 around the water injection bag 20 to make sufficient contact, and provides triaxial stress to the surrounding fractured rock mass 30 around the excavation hole. Among them, after the water injection bag 20 is filled with water, it expands along the axial direction and the radial direction of the anchor rod body 10 respectively, and applies an axial pressing force to the anchor fixing segment 11 and the free end 12 respectively, and applies a radial pressing force to the surrounding fractured rock mass 30 around the water injection bag 20 to make sufficient contact, and provides triaxial stress to the surrounding fractured rock mass 30 around the excavation hole. Among them, after the water injection bag 20 is filled with water, it expands along the axial direction and the radial direction of the anchor rod body 10 respectively, and applies an axial pressing force to the anchor fixing segment 11 and the free end 12 respectively, and applies a radial pressing force to the surrounding fractured rock mass 30 around the water injection bag 20 to make sufficient contact, and provides triaxial stress to the surrounding fractured rock mass 30 around the excavation hole. Among them, after the water injection bag 20 is filled with water, it expands along the axial direction and the radial direction of the anchor rod body 10 respectively, and applies an axial pressing force to the anchor fixing segment 11 and the free end 12 respectively, and applies a radial pressing force to the surrounding fractured rock mass 30 around the water injection bag 20 to make sufficient contact, and provides triaxial stress to the surrounding fractured rock mass 30 around the excavation hole. Among them, after the water injection bag 20 is filled with water, it expands along the axial direction and the radial direction of the anchor rod body 10 respectively, and applies an axial pressing force to the anchor fixing segment 11 and the free end 12 respectively, and applies a radial pressing force to the surrounding fractured rock mass 30 around the water injection bag 20 to make sufficient contact, and provides triaxial stress to the surrounding fractured rock mass 30 around the excavation hole.

[0022] According to the above embodiments, in this application, a water injection bag 20 made of a flexible material is installed on the anchor rod body 10 By injecting water, the water injection bag 20 with folds is expanded, and the water injection bag 20 is inflated to cause significant deformation in the radial direction, compressing the surrounding fractured rock mass and increasing the integrity of the surrounding fractured rock mass and the frictional force between the anchor rod structure and the surrounding fractured rock mass, ensuring the support and protection effects on the surrounding fractured rock mass of the anchor rod structure. This application is easy to operate, has low costs, greatly enhances the support effect of the anchor rod structure on the surrounding fractured rock mass, and can effectively guarantee the construction safety of the rock mass project in the surrounding fractured rock mass Compared with the conventional hydraulic expansion anchor rod that uses a rigid expansion housing and can only provide a limited radial force and cannot provide sufficient pressing force on the surrounding fractured rock mass around the excavation hole, thus failing to achieve the purpose of compressing the surrounding fractured rock mass, the water injection bag 20 made of a flexible material in this application can achieve large double deformations in the radial and axial directions. As a result, the outer surface of the water injection bag 20 can be in full contact with the surrounding fractured rock mass, compressing the surrounding fractured rock mass around the excavation hole, and applying triaxial stress to the surrounding fractured rock mass around the excavation hole in combination with the tensile stress applied from the free end 12 of the anchor rod body 10

[0023] Moreover, in this application, by fixing the water injection bag 20 in the middle section of the anchor rod body 10, the water injection bag 20 uniformly expands around the entire anchor rod during water injection and inflation, effectively avoiding stress concentration of the anchor rod. Compared with the conventional hydraulic expansion anchor rod using a rigid expansion housing, the hydraulic expansion housing and the anchor rod are separated, and the housing expands to cause the anchor rod to separate, which is avoided in this application can be in full contact with the surrounding fractured rock mass, compressing the surrounding fractured rock mass around the excavation hole, and applying triaxial stress to the surrounding fractured rock mass around the excavation hole in combination with the tensile stress applied from the free end 12 of the anchor rod body 10 can be applied to the surrounding fractured rock mass around the excavation hole

[0024] In addition, in this application, by fixing the water injection bag 20 in the middle section of the anchor rod body 10, when the water injection bag 20 is inflated, it expands uniformly around the entire anchor rod, effectively avoiding stress concentration of the anchor rod. Compared with the conventional hydraulic expansion anchor rod using a rigid expansion housing, the hydraulic expansion housing and the anchor rod are separated, and the housing expands to cause the anchor rod to separate, which is avoided in this application from separating, which is a problem that occurs in the conventional hydraulic expansion anchor rod using a rigid expansion housing and the housing expands to cause the anchor rod Press it to closely attach the anchor rod to the surrounding fractured rock mass, and due to the different unevenness of the rock around the excavation wall the anchor rod is prone to stress concentration and is likely to be damaged or destroyed.

[0025] The hydro - expansion anchor rod with the water injection bag 20 of the present application can be used for the support and protection of the surrounding fractured rock mass while the conventional anchor rod cannot adapt to the support and protection of the surrounding fractured rock mass, and the present application does not require an anchor fixing agent, and the frictional force between the outer surface of the water injection bag 20 and the excavation wall provides the support resistance

[0026] Among them, the water injection bag 20 is in close contact with the anchor rod body 10, and it is realized that there is no water leakage after the water injection bag 20 is injected with water.

[0027] For example, in the hydro - expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment as shown in FIG. 1, a telescopic folding belt 21 is provided along the axial direction of the anchor rod body 10 on the water injection bag 20, and the telescopic folding belt 21 expands along the axial direction of the anchor rod body 10 after the water injection bag 20 is injected with water.

[0028] For example, in the hydro - expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment as shown in FIGS. 1 and 3, a water injection pipe 22 is provided at the end of the water injection bag 20 facing the free end 12, and the water injection pipe 22 extends out from the surrounding fractured rock mass 30.

[0029] For example, in the hydro - expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment as shown in FIGS. 1 and 3, an external anchor is provided at the free end 12 of the anchor rod body 10 ​​​​​A tray 13 is provided, and tensile stress is applied to the anchor rod body 10 via the external anchor tray 13.

[0030] According to the above embodiment, an external anchor tray 13 is installed at the free end 12 of the anchor rod body 10 so that stress is applied to the anchor rod body 10 by the tension of the external anchor tray 13, and an anchor fixing effect is exerted on the surrounding fractured rock mass 30.

[0031] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment as shown in FIGS. 1 and 3, the water injection pipe 22 penetrates the external anchor tray 13 and extends out of the external anchor tray 13. After the external anchor tray 13 applies tensile stress to the anchor rod body 10, water is injected into the water injection bag 20 through the water injection pipe 22.

[0032] According to the above embodiment, by installing the water injection pipe 22 of the water injection bag 20 outside and extending it out of the external anchor tray 13, water can be easily injected into the water injection bag 20 after the tension of the external anchor tray 13.

[0033] For example, in a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass provided by one embodiment as shown in FIGS. 2 and 4, a rust prevention layer 14 is applied to the outer wall surface where the anchor rod body 10 contacts the water injection bag 20.

[0034] According to the above embodiment, by applying the rust prevention layer 14 to the contact area between the anchor rod body 10 and the water injection bag 20, it is possible to prevent the anchor rod body 10 from reacting with water and corroding during long-term use, which may affect the strength of the anchor rod body 10.

[0035] For example, in a hydraulic expansion anchor rod suitable for a surrounding fractured rock mass provided by one embodiment, as shown in FIG. 1, two expansion and contraction fold belts 21 are provided at intervals along the axial direction of the anchor rod body 10 in the water injection bag 20, and one of the expansion and contraction fold belts 21 expands toward the free end 12 after water injection, and the other expansion and contraction fold belt 21 expands toward the anchor fixing segment 11 after water injection.

[0036] For example, in a hydraulic expansion anchor rod suitable for a surrounding fractured rock mass provided by one embodiment, after water injection, the water injection bag 20 expands in the axial direction of the anchor rod body 10 through the two expansion and contraction fold belts 21, and both ends of the water injection bag 20 are in contact with the anchor fixing segment 11 and the external anchor tray 13 respectively, and an axial pressing force is applied to the anchor fixing segment 11 and the external anchor tray 13.

[0037] After water is injected into the water injection bag 20 through the water injection pipe 22, a form of the expanded water injection bag is formed. As shown in FIG. 3, at this time, the water injection bag 20 is in close contact with the surrounding fractured rock mass 13 of the water injection bag 20 due to the water injection expansion action, and the water injection bag 20 also expands axially through the expansion and contraction fold belt 21 and contacts the anchor fixing segment 11 and the external anchor tray 13. Due to the expansion action of the water injection bag 20, the pressing force of the water injection bag 20 on the surrounding fractured rock mass 30 and the frictional force between the water injection bag 20 and the surrounding fractured rock mass 30 become the anchor fixing force, and further prevent the reduction of the anchor fixing action due to the relaxation of the tensile stress during the long-term use of the anchor rod body 10. The pressing force of the water injection bag 20 on the surrounding fractured rock mass 30 and the frictional force between the water injection bag 20 and the surrounding fractured rock mass 30 become the anchor fixing force, and further prevent the reduction of the anchor fixing action due to the relaxation of the tensile stress during the long-term use of the anchor rod body 10. In addition, the pressing force of the anchor fixing segment 11 and the external anchor tray 13 at both ends of the water injection bag 20 and the radial pressing force of the water injection bag 20 on the surrounding fractured rock mass 30 are in a three-directional stress state. ​​​​​​​​​​​ It can be effectively formed and is useful for fixing and stabilizing rock masses.

[0038] The second aspect of the present application provides a method of using the hydraulic expansion anchor rod suitable for surrounding fractured rock masses, including the following steps:

[0039] S1 Insert and fix the head of the anchor fixing segment 11 of the anchor rod body 10 into the excavation hole. .

[0040] S2 Apply stress to the anchor rod body 10 by tension with the external anchor tray 13.

[0041] S3 Inject water into the water injection bag 20 through the water injection pipe 22, expand the water injection bag 20 with folds to expand the water injection bag 20 in the radial direction of the anchor rod body 10, and fully contact the surrounding fractured rock mass 30 around the water injection bag 20 to apply a radial pressing force. Then, expand the expansion and contraction fold zone 21 on the water injection bag 20 to expand the water injection bag 20 in the axial direction of the anchor rod body 10 and apply an axial pressing force to the anchor fixing segment 11 and the external anchor tray 13. to expand it in the radial direction of the anchor rod body 10, make sufficient contact with the surrounding fractured rock mass 30 around the water injection bag 20 to apply a radial pressing force, and expand the expansion and contraction fold zone 21 on the water injection bag 20 to expand it in the axial direction of the anchor rod body 10 and apply an axial pressing force to the anchor fixing segment 11 and the external anchor tray 13. and expand the expansion and contraction fold zone 21 on the water injection bag 20 to expand it in the axial direction of the anchor rod body 10 and apply an axial pressing force to the anchor fixing segment 11 and the external anchor tray 13. to expand it in the axial direction of the anchor rod body 10 and apply an axial pressing force to the anchor fixing segment 11 and the external anchor tray 13. Apply an axial pressing force to the anchor fixing segment 11 and the external anchor tray 13.

[0042] Although the embodiments of the present application have been disclosed as above, it is not limited to the operations described in the specification and embodiments, and can be fully applied to various fields suitable for the present application. Those skilled in the art can easily modify this, so without departing from the general concepts defined in the claims and the equivalent scope, the present application is not limited to the specific details and the drawings described herein. It is not limited to the operations defined in the specification and embodiments, and can be fully applied to various fields suitable for the present application. Those skilled in the art can easily modify this, so without departing from the general concepts defined in the claims and the equivalent scope, the present application is not limited to the specific details and the drawings described herein. Those skilled in the art can easily modify this, so without departing from the general concepts defined in the claims and the equivalent scope, the present application is not limited to the specific details and the drawings described herein. Without departing from the general concepts defined in the claims and the equivalent scope, the present application is not limited to the specific details and the drawings described herein. The present application is not limited to the specific details and the drawings described herein.

Claims

1. A hydraulic expansion anchor rod suitable for surrounding fractured rock masses, comprising: an anchor rod body; One end of the anchor rod body extends and is fixed to the surrounding fractured rock mass around the excavation hole, and forms an anchor fixing segment. The other end of the anchor rod body is a free end and extends out of the surrounding fractured rock mass. By applying tensile stress, the surrounding fractured rock mass is fixed by the anchor. The water injection bag is mounted on the anchor rod body and is in close contact with the anchor rod body. and The water injection bag is located between the anchor fixing segment and the free end. Among them, after the water injection bag is filled with water, it expands along the axial direction and the radial direction of the anchor rod body respectively. and Apply axial pressing forces to the anchor fixing segment and the free end respectively. Apply a radial pressing force to the surrounding fractured rock mass around the water injection bag to make sufficient contact, providing triaxial stress to the surrounding fractured rock mass around the excavation hole. The water injection bag is provided with a telescopic folding belt along the axial direction of the anchor rod body. and After the water injection bag is filled with water, it expands along the axial direction of the anchor rod body through the telescopic folding belt. A water injection pipe is provided at the end of the water injection bag facing the free end. and The water injection pipe extends out of the surrounding fractured rock mass. An outer anchor tray is provided at the free end of the anchor rod body. Tensile stress is applied to the anchor rod body through the outer anchor tray. The water injection bag is provided with two telescopic folding belts at intervals along the axial direction of the anchor rod body. One of the telescopic folding belts expands towards the free end after water injection, and the other telescopic folding belt expands towards the anchor fixing segment after water injection. A hydraulic expansion anchor rod suitable for surrounding fractured rock masses.

2. The water injection pipe penetrates through the outer anchor tray and extends out of the outer anchor tray. Thereby, after the outer anchor tray applies tensile stress to the anchor rod body, water is injected into the water injection bag through the water injection pipe. The hydraulic expansion anchor rod suitable for surrounding fractured rock masses according to Claim 1.

3. An anti-rust layer is applied to the outer wall surface where the anchor rod body and the water injection bag are in contact. The hydraulic expansion anchor rod suitable for surrounding fractured rock masses according to Claim 1.

4. After the water injection bag is filled with water, it expands along the axial direction of the anchor rod body through the two telescopic folding belts. and ​ ​ ​ ​ ​ Both ends of the water injection bag are respectively in contact with the anchor fixing segment and the external anchor tray, and apply an axial pressing force to the anchor fixing segment and the external anchor tray. The hydraulic expansion anchor rod suitable for the surrounding fractured rock mass according to claim 1. **Claim 5** A method of using a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass according to any one of claims 1 to 4, comprising the following steps: S1 Insert and fix the head of the anchor fixing segment of the anchor rod body into the excavation hole. S2 Apply stress to the anchor rod body by tension with the external anchor tray. S3 Inject water into the water injection bag through the water injection pipe. Expand the water injection bag with folds to expand the water injection bag in the radial direction of the anchor rod body. Sufficiently contact the surrounding fractured rock mass around the water injection bag to apply a radial pressing force. Then, expand the telescopic fold zone on the water injection bag to expand the anchor rod body in the axial direction. Apply an axial pressing force to the anchor fixing segment and the external anchor tray. The method of using a hydraulic expansion anchor rod suitable for the surrounding fractured rock mass. ​ ​

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