Stability control method for raise boring construction shaft pre-support surrounding rock

Abstract

The invention provides a raise boring construction shaft pre-support surrounding rock stability control method, and belongs to the technical field of mine construction.The raise boring construction shaft pre-support surrounding rock stability control method includes the steps that shaft site selection is optimized through the position of a fracture zone, the trend of the fracture zone and the fracture degree of the fracture zone, the position of a shaft is determined, and a shaft temporary support area and a shaft permanent support area are divided; secondly, the crushed zone is pretreated, specifically, glass fiber reinforced plastic anchor rods are vertically installed in the temporary supporting area of the shaft in a radial and outward mode, steel bar anchor rods are arranged in the permanent supporting area of the shaft at a preset angle, and the shaft is pretreated before construction, so that the phenomenon that the shaft is blocked due to collapse of the crushed zone in the construction process of the guide hole of the shaft is effectively prevented; and continuous large-scale collapse of the crushed zone in the slope expanding process and after the shaft is formed is prevented, so that the integrality and stability of shaft surrounding rock in raise-boring construction crossing the crushed zone are improved, and the situation that the shaft is difficult to treat after being damaged is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine construction, in particular to a method for controlling the stability of pre-supporting surrounding rock of a shaft in a counter-bore drilling construction. BACKGROUND

[0002] In the process of mine construction, the counter-bore, as a blind shaft connecting different roadways underground, is an important shaft and roadway project, and is usually constructed by counter-bore drilling method. The counter-bore drilling method has the following advantages: on the one hand, the equipment and personnel are operated on the operation platform, avoiding the entry of personnel into the shaft, fundamentally improving the operation conditions and effectively reducing the labor intensity; on the other hand, the counter-bore construction is carried out from bottom to top, causing less disturbance to the rock mass around the shaft wall, and the forming quality of the shaft wall can be better controlled during the expansion of the shaft wall, reducing overbreak and underbreak, improving the engineering quality, and making the shaft wall smoother, which is helpful to the long-term stability of the shaft.

[0003] However, in the process of counter-bore drilling construction, unfavorable strata such as fracture zones are often encountered. When the counter-bore drilling expands, it will destroy the original stress distribution of the strata, causing damage to the surrounding rock during and after construction, and even causing the shaft to collapse, thereby blocking the lower position chamber, increasing the amount of shaft construction, and causing additional problems such as personnel safety. At present, the existing technology mainly focuses on repairing and governing the shaft wall after the shaft collapses, and does not effectively improve the overall strength of the surrounding rock of the shaft passing through the fracture zone and other unfavorable strata before construction. This treatment method not only increases the workload, reduces the work efficiency, and increases the construction cost, but also makes the shaft construction more uncertain. SUMMARY

[0004] To solve the above problems in the prior art, the present application provides a method for controlling the stability of pre-supporting surrounding rock of a shaft in a counter-bore drilling construction. The present application optimizes the site selection of the shaft by the position, direction and fracture degree of the fracture zone, determines the position of the shaft and divides the temporary support area and the permanent support area of the shaft. Secondly, the fracture zone is pretreated, mainly including installing glass steel anchor rods vertically outward in the temporary support area of the shaft and arranging steel anchor rods at a predetermined angle in the permanent support area of the shaft. By pretreating the shaft before construction, the method effectively prevents the shaft from being blocked due to the collapse of the fracture zone during construction, and prevents large-scale collapse of the fracture zone during the expansion process and after the shaft is formed, thereby improving the integrity and stability of the surrounding rock of the shaft passing through the fracture zone, and avoiding the difficulty in governing the damaged shaft. To achieve the above purpose, the technical solution is as follows: The present application provides a method for controlling the stability of pre-supporting surrounding rock of a shaft in a counter-bore drilling construction, which comprises: S1, based on the geological survey of the reverse drilling pre-construction area, predicting the position of the fracture zone, the strike of the fracture zone and the damage depth of the fracture zone; S2, according to the position of the fracture zone, the strike of the fracture zone and the damage depth of the fracture zone, determining the wellbore construction area and the wellbore pilot hole position; S3, according to the wellbore construction area and the wellbore pilot hole position, determining the plastic zone of the wellbore surrounding rock, obtaining the wellbore temporary support area and the wellbore permanent support area; S4, according to the wellbore temporary support area, by installing glass steel anchor rod, obtaining the stable temporary support area; S5, according to the wellbore permanent support area, by installing steel anchor rod, obtaining the stable permanent support area; S6, according to the wellbore pilot hole position, the stable temporary support area and the stable permanent support area, installing the reverse drilling machine and constructing, obtaining the stable wellbore.

[0005] Optionally, in the S2, according to the position of the fracture zone, the strike of the fracture zone and the damage depth of the fracture zone, determining the wellbore construction area and the wellbore pilot hole position, comprising: According to the position of the fracture zone, the strike of the fracture zone and the damage depth of the fracture zone, controlling the distance between the fracture zone and the upper section or the lower section of the wellbore to be not more than 30m, determining the wellbore construction area and the wellbore pilot hole position.

[0006] Optionally, in the S3, according to the wellbore construction area and the wellbore pilot hole position, determining the plastic zone of the wellbore surrounding rock, obtaining the wellbore temporary support area and the wellbore permanent support area, comprising: S31, according to the wellbore pilot hole position, determining the plastic zone of the wellbore surrounding rock, selecting the area between the outside of the wellbore pilot hole and the wellbore wall, obtaining the wellbore temporary support area; S32, according to the plastic zone of the wellbore surrounding rock, selecting the area between the wellbore wall and the stable rock stratum, obtaining the wellbore permanent support area.

[0007] Optionally, in the S4, according to the wellbore temporary support area, by installing glass steel anchor rod, obtaining the stable temporary support area, comprising: According to the wellbore temporary support area, the glass steel anchor rods are uniformly staggered arranged from the center boundary of the wellbore pilot hole wall to the outer ring of the wellbore wall, obtaining the stable temporary support area, the included angle between the adjacent glass steel anchor rods and the center line of the wellbore pilot hole position is 30°~60°, and the glass steel anchor rod spacing is 0.5~1.2m.

[0008] Optionally, in the S5, according to the wellbore permanent support area, by installing steel anchor rod, obtaining the stable permanent support area, comprising: According to the wellbore permanent support area, the steel anchor rods are arranged in the annularly uniform staggered distribution of not less than two circles outside the wellbore wall, the first circle of steel anchor rods close to the wellbore wall is the inner circle anchor rod, and the second circle and the outside steel anchor rods are the outer circle anchor rods, the steel anchor rod is a vertical anchor rod in the inner circle anchoring hole, the steel anchor rod has an angle of 60°~90° with the horizontal plane in the outer circle anchoring hole, and the distance between adjacent steel anchor rods is 0.5~2m.

[0009] Optionally, the glass steel anchor rods are all vertical anchor rods, the effective length of the glass steel anchor rod is not less than 1.5 times the depth of the broken zone, and the diameter of the glass steel anchor rod is 18~22mm.

[0010] Optionally, the steel anchor rod is a hollow grouting anchor rod, the effective length of the hollow grouting anchor rod is not less than 1.5 times the depth of the broken zone, and the diameter of the hollow grouting anchor rod is 25~38mm.

[0011] Optionally, the arrangement rule of the glass steel anchor rod comprises: Rule 1: If the broken zone is close to the upper section, the glass steel anchor rod is arranged from the upper section downward, and the glass steel anchor rod needs to penetrate the broken zone and embed in the stable rock layer by not less than 500mm; Rule 2: If the broken zone is close to the lower section, the glass steel anchor rod is arranged from the lower section upward, and the glass steel anchor rod needs to penetrate the broken zone and embed in the stable rock layer by not less than 500mm.

[0012] Optionally, the arrangement rule of the steel anchor rod comprises: Rule 3: If the broken zone is close to the upper section, the steel anchor rod is arranged from the upper section downward, and the steel anchor rod needs to penetrate the broken zone and embed in the stable rock layer by not less than 500mm; Rule 4: If the broken zone is close to the lower section, the steel anchor rod is arranged from the lower section upward, and the steel anchor rod needs to penetrate the broken zone and embed in the stable rock layer by not less than 500mm.

[0013] Compared with the prior art, the technical scheme of the present application has at least the following beneficial effects: The glass steel anchor rod has the characteristics of light weight, large deflection and high strength, can be cut by the reverse drilling machine in the construction process without damaging the drill bit, and can constrain the displacement of large broken rocks in the broken zone, prevent the large area instantaneous collapse of the wellbore in the broken zone during the guide hole construction, effectively improve the integrity and stability of the rock in the wellbore, the hollow self-feeding grouting anchor rod is used for the steel anchor rod, the hollow self-feeding grouting anchor rod is used for the steel anchor rod, the adhesion of the broken zone can be more effectively enhanced by using the hollow self-feeding grouting anchor rod around the well wall, the bearing capacity of the stratum is improved, the collapse of the wellbore after the construction is prevented, and the foundation is created for the subsequent support process of improving the stability of the well wall, the position of the broken zone, the trend of the broken zone and the broken degree of the broken zone are optimized, the position of the wellbore is determined, and the temporary support area and the permanent support area of the wellbore are divided, the broken zone is pretreated, mainly including vertically installing the glass steel anchor rod outwardly in the temporary support area of the wellbore and arranging the steel anchor rod at a predetermined angle in the permanent support area of the wellbore, the wellbore is pretreated before construction, the wellbore is effectively prevented from being blocked due to the collapse of the broken zone during the construction of the guide hole of the wellbore, and the large-scale collapse of the broken zone is prevented during the expansion process and after the wellbore is formed, so that the integrity and stability of the surrounding rock of the reverse drilling construction wellbore passing through the broken zone are improved, and the situation that the wellbore is difficult to treat after being damaged is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0015] Figure 1 is the flow chart of the reverse drilling construction wellbore pre-supporting surrounding rock stability control method embodiment of the present application; Figure 2 is the schematic diagram of the wellbore support in the reverse drilling construction area in the reverse drilling construction wellbore pre-supporting surrounding rock stability control method embodiment of the present application; Figure 3 is the top view of the wellbore support in the reverse drilling construction area in the reverse drilling construction wellbore pre-supporting surrounding rock stability control method embodiment of the present application.

[0016] The figure number is explained: the reverse drilling pre-construction area 1, the wellbore surrounding rock plastic zone 2, the broken zone 3, the stable rock stratum 4, the steel anchor rod 5, the glass steel anchor rod 6, the wellbore guide hole 7. DETAILED DESCRIPTION

[0017] The technical solutions in the present application will be described below with reference to the drawings.

[0018] In the embodiments of the present application, the words such as "example", "for example", etc. are used to represent an example, illustration or description. Any embodiment or design scheme described as "example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the word "example" is intended to present the concept in a specific manner. In addition, in the embodiments of the present application, the meaning expressed by "and / or" can be both, or can be one of the two.

[0019] In order to make the technical problems, technical solutions and advantages to be solved by the present application clearer, the following will be described in detail in combination with the drawings and specific embodiments.

[0020] As Figure 2 shown in the schematic diagram of the shaft lining of the reverse circulation drilling construction area in the reverse circulation drilling construction shaft pre-supporting surrounding rock stability control method embodiment of the present application and as Figure 3 shown in the top view of the shaft lining of the reverse circulation drilling construction area in the reverse circulation drilling construction shaft pre-supporting surrounding rock stability control method embodiment of the present application, the present embodiment is to perform reverse circulation drilling construction from-80 middle section to-180 middle section in a certain mine, and the diameter of the shaft is 3 m, which is used as a ventilation shaft.

[0021] As Figure 1 shown in the flowchart of the reverse circulation drilling construction shaft pre-supporting surrounding rock stability control method embodiment of the present application, the method comprises: S1, based on the geological investigation of the reverse circulation drilling pre-construction area 1, predicting the position of the fracture zone 3, the trend of the fracture zone 3 and the damage depth of the fracture zone 3; Specifically, the geological investigation supplements the geological information of the construction area through borehole peeping, three-dimensional scanning and other means.

[0022] S2, according to the position of the fracture zone 3, the trend of the fracture zone 3 and the damage depth of the fracture zone 3, determining the shaft construction area and the position of the shaft pilot hole 7; Specifically, according to the position of the fracture zone 3, the trend of the fracture zone 3 and the damage depth of the fracture zone 3, determining the shaft construction area and the position of the shaft pilot hole 7, comprising: According to the position of the fracture zone 3, the trend of the fracture zone 3 and the damage depth of the fracture zone 3, controlling the distance between the fracture zone 3 and the upper section or the lower section of the shaft to be not more than 30 m, and determining the shaft construction area and the position of the shaft pilot hole 7.

[0023] Further, in the present embodiment, the fracture zone 3 cannot be avoided due to the shaft construction, the fracture zone 3 in the shaft construction area has an angle of 50° with the horizontal, is about 3 m wide and is about 10 m away from the lower section; the position of the shaft pilot hole 7 is determined, and the diameter is 216 mm.

[0024] S3, determining the plastic zone 2 of the wellbore surrounding rock according to the wellbore construction area and the position of the wellbore pilot hole 7, obtaining the temporary support area of the wellbore and the permanent support area of the wellbore; Specifically, in this embodiment, the radius of the plastic zone 2 of the wellbore surrounding rock is about 3m; Specifically, in this embodiment, S3, according to the wellbore construction area and the position of the wellbore pilot hole 7, the plastic zone 2 of the wellbore surrounding rock is determined, and the temporary support area of the wellbore and the permanent support area of the wellbore are obtained, comprising: S31, according to the position of the wellbore pilot hole 7, determining the plastic zone 2 of the wellbore surrounding rock, selecting the area between the outside of the wellbore pilot hole 7 and the wellbore wall, and obtaining the temporary support area of the wellbore; S32, according to the plastic zone 2 of the wellbore surrounding rock, selecting the area between the wellbore wall and the stable rock stratum 4, and obtaining the permanent support area of the wellbore.

[0025] S4, according to the temporary support area of the wellbore, installing glass steel anchor rod 6 to obtain a stable temporary support area; Specifically, S4, according to the temporary support area of the wellbore, installing glass steel anchor rod 6 to obtain a stable temporary support area, comprising: According to the temporary support area of the wellbore, the glass steel anchor rod 6 is arranged uniformly and staggered from the center boundary of the wellbore pilot hole 7 wall to the outer ring of the wellbore wall, and the included angle between the adjacent glass steel anchor rod 6 and the center line of the wellbore pilot hole 7 position is 30°-60°, and the spacing of the glass steel anchor rod 6 is 0.5-1.2m.

[0026] Further, the glass steel anchor rod 6 is a vertical anchor rod, the effective length of the glass steel anchor rod 6 is not less than 1.5 times the depth of the fracture zone 3, and the diameter of the glass steel anchor rod 6 is 18-22mm.

[0027] The arrangement rule of the glass steel anchor rod 6 comprises: Rule 1: If the fracture zone 3 is close to the upper section, the glass steel anchor rod 6 is arranged from the upper section to the lower section, and the glass steel anchor rod 6 needs to penetrate the fracture zone 3 and embed in the stable rock stratum 4 by not less than 500mm; Rule 2: If the fracture zone 3 is close to the lower section, the glass steel anchor rod 6 is arranged from the lower section to the upper section, and the glass steel anchor rod 6 needs to penetrate the fracture zone 3 and embed in the stable rock stratum 4 by not less than 500mm.

[0028] Further, in the embodiment, to ensure that the glass steel anchor rods 6 in the temporary support area of the shaft can effectively play a role and ensure the maximization of economic benefits, the diameter of the glass steel anchor rod 6 is 22 mm, the length is 17 m, the number of the glass steel anchor rod 6 in each circle is 6, the included angle of the center line of the glass steel anchor rod 6 in each adjacent circle and the position of the shaft guide hole 7 is 60°, the spacing between the first adjacent glass steel anchor rod 6 is 0.5 m, and the spacing between the second adjacent glass steel anchor rod 6 is 1 m.

[0029] S5, according to the shaft permanent support area, a stable permanent support area is obtained by installing the steel anchor rod 5; Specifically, in S5, according to the shaft permanent support area, a stable permanent support area is obtained by installing the steel anchor rod 5, which includes: According to the shaft permanent support area, the steel anchor rod 5 is arranged in an annular and staggered manner outside the shaft wall, and the number of the steel anchor rod 5 is not less than two circles. The first circle of the steel anchor rod 5 near the shaft wall is an inner circle anchor rod, and the second circle and the outside of the steel anchor rod are outer circle anchor rods. The steel anchor rod 5 in the inner circle anchoring hole is a vertical anchor rod, and the included angle between the steel anchor rod 5 in the outer circle anchoring hole and the horizontal plane is 60°-90°. The spacing between the adjacent steel anchor rods 5 is 0.5-2 m.

[0030] Further, the effective length of the steel anchor rod 5 is not less than 1.5 times the depth of the fracture zone 3, the diameter of the steel anchor rod 5 is 25-38 mm, and the spacing between the adjacent steel anchor rods 5 is 0.5-2 m.

[0031] The arrangement rule of the steel anchor rod 5 includes: Rule 3: If the fracture zone 3 is close to the upper section, the steel anchor rod 5 is arranged from the upper section downward, and the steel anchor rod 5 needs to penetrate the fracture zone 3 and be embedded in the stable rock layer 4 by not less than 500 mm; Rule 4: If the fracture zone 3 is close to the lower section, the steel anchor rod 5 is arranged from the lower section upward, and the steel anchor rod 5 needs to penetrate the fracture zone 3 and be embedded in the stable rock layer 4 by not less than 500 mm.

[0032] Further, in the embodiment, the number of anchoring hole positions in each circle of the steel anchor rod 5 is 12, the inner circle anchoring hole is a vertical hole, the outer circle anchoring hole is punched into the rock mass at a predetermined angle with the horizontal angle of 85°, and the included angle between the center line of the two adjacent steel anchor rods 5 closest to the outer circle anchoring hole and the inner circle anchoring hole is 60°. The steel anchor rod 5 is selected to be 38 mm, the length of the steel anchor rod 5 in the inner circle anchoring hole is 18 m, and the length of the steel anchor rod 5 in the outer circle anchoring hole is 20 m.

[0033] S6, according to the shaft guide hole 7 position, the stable temporary support area and the stable permanent support area, a stable shaft is obtained by installing the reverse drilling machine and construction.

[0034] The application provides a method and system for controlling the stability of pre-supporting surrounding rock of a shaft drilled by a reverse drilling machine, which first adopts a glass steel anchor rod, has the characteristics of light weight, large deflection and high strength, and can be cut by the reverse drilling machine without damaging the drill bit and restricting the displacement of large broken rocks in the broken zone during construction, preventing large-area instantaneous collapse of the shaft in the broken zone during the guide hole construction, effectively improving the integrity and stability of the rock inside the shaft, secondly, the hollow self-feeding grouting anchor rod is used to support the broken zone, which can effectively enhance the adhesion of the broken zone and improve the bearing capacity of the stratum, prevent collapse of the shaft after construction, and create a foundation for subsequent support procedures to improve the stability of the shaft wall, finally, the position of the broken zone, the trend of the broken zone and the degree of fragmentation of the broken zone are optimized to determine the position of the shaft and divide the temporary support area and the permanent support area of the shaft; secondly, the broken zone is pretreated, mainly including installing glass steel anchor rods radially outward and vertically in the temporary support area of the shaft and arranging steel anchor rods at a predetermined angle in the permanent support area of the shaft, and by pretreating the shaft before construction, effectively preventing the shaft from being blocked due to collapse of the broken zone during the construction process, and preventing large-scale collapse of the broken zone during the expansion process and after the shaft is formed, thereby improving the integrity and stability of the surrounding rock of the shaft drilled through the broken zone, and avoiding the difficulty in treating the damaged shaft.

[0035] It can be understood that the application is described by the above embodiments, which should not be interpreted as limiting the embodiments and the scope of the application. Those skilled in the art know that various changes or equivalent replacements can be made to the features and embodiments without departing from the spirit and scope of the application. In addition, under the guidance of the application, the features and embodiments can be modified to adapt to specific conditions and materials without departing from the spirit and scope of the application. Therefore, the application is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the application are within the scope of the application.

Claims

1. A method for controlling the stability of pre-supporting surrounding rock in a shaft during uphole drilling construction, characterized in that, The method comprises: S1, based on the geological survey of the reverse drilling pre-construction area, predicting the position of the fracture zone, the trend of the fracture zone and the damage depth of the fracture zone; S2, according to the position of the fracture zone, the trend of the fracture zone and the damage depth of the fracture zone, determine the wellbore construction area and the wellbore pilot hole position; S3, according to the wellbore construction area and the wellbore pilot hole position, determine the plastic zone of the wellbore surrounding rock, get the wellbore temporary support area and the wellbore permanent support area; S4, according to the wellbore temporary support area, by installing glass steel anchor rod, get the stable temporary support area; S5, according to the wellbore permanent support area, by installing steel anchor rod, get the stable permanent support area; S6, according to the wellbore pilot hole position, the stable temporary support area and the stable permanent support area, install the reverse drilling machine and construction, get the stable wellbore.

2. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 1, characterized by, In S2, according to the position of the fracture zone, the trend of the fracture zone and the damage depth of the fracture zone, determine the wellbore construction area and the wellbore pilot hole position, comprising: According to the position of the fracture zone, the trend of the fracture zone and the damage depth of the fracture zone, control the distance between the fracture zone and the upper section of the wellbore or the lower section of the wellbore not more than 30m, determine the wellbore construction area and the wellbore pilot hole position.

3. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 1, characterized by, In S3, according to the wellbore construction area and the wellbore pilot hole position, determine the plastic zone of the wellbore surrounding rock, get the wellbore temporary support area and the wellbore permanent support area, comprising: S31, according to the wellbore pilot hole position, determine the plastic zone of the wellbore surrounding rock, select the area between the outside of the wellbore pilot hole and the wellbore wall, get the wellbore temporary support area; S32, according to the plastic zone of the wellbore surrounding rock, select the area between the wellbore wall and the stable rock formation, get the wellbore permanent support area.

4. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 1, characterized by, In S4, according to the wellbore temporary support area, by installing glass steel anchor rod, get the stable temporary support area, comprising: According to the wellbore temporary support area, the glass steel anchor rod is uniformly staggered arranged from the center boundary of the wellbore pilot hole wall to the outer ring of the wellbore wall, get the stable temporary support area, the included angle between the center line of adjacent glass steel anchor rod and the wellbore pilot hole position is 30°~60°, the distance between the glass steel anchor rods is 0.5~1.2m.

5. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 1, characterized by, In S5, according to the wellbore permanent support area, by installing steel anchor rod, get the stable permanent support area, comprising: According to the wellbore permanent support area, the steel anchor rod is uniformly staggered distributed in the outer ring of the wellbore wall, not less than two circles of steel anchor rods, the first circle of steel anchor rod near the wellbore wall is inner circle anchor rod, the second circle and outer steel anchor rod is outer circle anchor rod, the steel anchor rod in the inner circle anchoring hole is vertical anchor rod, the included angle between the steel anchor rod and the horizontal plane in the outer circle anchoring hole is 60°~90°, the distance between adjacent steel anchor rods is 0.5~2m.

6. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 4, characterized by, The glass steel anchor rod is all vertical anchor rod, the effective length of the glass steel anchor rod is not less than 1.5 times of the depth of the fracture zone, the diameter of the glass steel anchor rod is 18~22 mm.

7. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 5, characterized by, The steel reinforcement anchor rod is a hollow grouting anchor rod, the effective length of the hollow grouting anchor rod is not less than 1.5 times the depth of the fracture zone, and the diameter of the hollow grouting anchor rod is 25~38mm.

8. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 6, characterized by, The arrangement rules for the fiberglass anchors include: Rule 1: If the fracture zone is close to the upper section, the fiberglass anchors shall be arranged from the upper section downwards, and the fiberglass anchors shall penetrate the fracture zone and be embedded in the stable rock layer for no less than 500mm. Rule 2: If the fracture zone is close to the lower section, the fiberglass anchors shall be arranged from the lower section upwards, and the fiberglass anchors shall penetrate the fracture zone and be embedded in the stable rock layer for no less than 500mm.

9. The pre-supporting rock stability control method for a shaft construction wellbore according to claim 7, characterized by, The arrangement rules for the steel anchor rods include: Rule 3: If the fractured zone is close to the upper section, the steel anchors shall be arranged from the upper section downwards, and all steel anchors shall penetrate the fractured zone and be embedded in the stable rock layer for no less than 500mm. Rule 4: If the fractured zone is close to the lower section, the steel anchor rods shall be arranged from the lower section upwards, and all steel anchor rods shall penetrate the fractured zone and be embedded in the stable rock layer for no less than 500mm.

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