Anchoring device and method with site-specific weakening and multi-stage negative pressure energy absorption

Abstract

The application discloses an anchoring device and method with point weakening and multi-stage negative pressure energy absorption, which comprises an anchor rod, a first energy absorption assembly and a second energy absorption assembly. The anchor rod comprises a pre-tightening section, a weakening section and an anchoring section connected in sequence. The first energy absorption assembly comprises a first shell and a first closed ring, both of which are sleeved on the pre-tightening section. The first closed ring divides the internal space of the first shell into a positive pressure cavity and a negative pressure cavity. The second energy absorption assembly comprises a second shell, a second closed ring and a third closed ring, both of which are sleeved on the anchor rod. The second shell is filled with a non-Newtonian fluid. The anchoring device with point weakening and multi-stage negative pressure energy absorption can meet the requirements of energy absorption and pressure deformation of large deformation roadways through multi-stage negative pressure energy absorption and point weakening, thereby ensuring the effectiveness of the whole anchoring system.

Description

Technical Field

[0001] This invention belongs to the field of tunnel support technology, and particularly relates to an anchoring device and method for fixed-point weakening and multi-stage negative pressure energy absorption. Background Technology

[0002] With the increasing number and depth of coal mine roadways, large-scale tunnel construction faces increasingly complex geological conditions, and geological stability issues, especially large deformation of the surrounding rock, frequently occur. In areas with large deformation of the surrounding rock, when the anchor cable exceeds its ultimate bearing deformation length or strength, the anchor cable will break and fail, which may lead to underground engineering safety accidents.

[0003] In soft rock slopes, foundation pits, mine roadways, and deep underground engineering, when using prestressed anchor cable support, the yield deformation of the steel strands used is only 3-5% of the free length of the anchor cable. When the surrounding rock mass deforms significantly, the anchor cable will be stretched beyond its yield strength and break. At the same time, the deformation of the surrounding rock due to the orifice fracture can generate a large transverse shear stress, which in turn causes transverse shear failure of the anchor cable, resulting in the inability to fully utilize the tensile strength of the anchor cable. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose an anchoring device with fixed-point weakening and multi-stage negative pressure energy absorption. This anchoring device, through multi-stage negative pressure energy absorption and fixed-point weakening, adapts to the requirements of large deformation roadways, such as energy absorption and pressure deformation, ensuring the effectiveness of the entire anchoring system.

[0005] A second aspect of the present invention also proposes an anchoring method that uses point weakening and multi-stage negative pressure energy absorption.

[0006] The anchoring device for fixed-point weakening and multi-stage negative pressure energy absorption according to an embodiment of the present invention includes an anchor rod, a first energy-absorbing component, and a second energy-absorbing component. The anchor rod includes a pre-tightening section, a weakening section, and an anchoring section connected in sequence. The first energy-absorbing component includes a first housing and a first sealing ring. The first housing is sleeved on the pre-tightening section, and the first sealing ring is sleeved on the anchor rod and located inside the first housing. The outer peripheral wall of the first sealing ring abuts against the inner peripheral wall of the first housing to divide the internal space of the first housing into a positive pressure chamber and a negative pressure chamber. The negative pressure chamber is farther away from the anchoring section than the positive pressure chamber. The second energy-absorbing component includes a second housing, a second sealing ring, and a third sealing ring. The second housing is sleeved on the weakening section, and both the second and third sealing rings are sleeved on the anchor rod. The outer peripheral walls of the second and third sealing rings abut against the inner peripheral wall of the second housing. The second housing is filled with a non-Newtonian fluid.

[0007] The anchoring device of the present invention, which features fixed-point weakening and multi-stage negative pressure energy absorption, increases the pre-tightening force between the first shell and the anchor hole by pressurizing the positive pressure chamber. Through the negative pressure chamber, when the surrounding rock deforms, the relative displacement between the first sealed ring and the first shell causes a change in pressure within the positive and negative pressure chambers, absorbing the energy transferred to the anchoring device by the surrounding rock deformation and reducing the risk of pre-tightening section breakage. Through the second energy-absorbing component, when the impact force occurs instantaneously, the non-Newtonian fluid becomes solid to improve impact resistance. When the stress on the anchor rod exceeds the weakened strength, the fixed-point weakening point of the weakened section breaks, and the second and third sealed rings move towards the end of the second shell and deform to absorb the energy transferred to the anchoring device by the surrounding rock deformation. Simultaneously, the second shell and the non-Newtonian fluid continue to perform anchoring functions.

[0008] In some embodiments, the first energy-absorbing component further includes a first pressure switch and a second pressure switch, wherein the first pressure switch is connected to the first housing and communicates with the negative pressure chamber, and the second pressure switch is connected to the first housing and communicates with the positive pressure chamber.

[0009] In some embodiments, both the first pressure switch and the second pressure switch are digital display pressure switches.

[0010] In some embodiments, both the second sealing ring and the third sealing ring are provided with pressure control valves.

[0011] In some embodiments, there are multiple second energy-absorbing components, which are distributed at intervals along the axial direction of the anchor bolt.

[0012] In some embodiments, the anchor bolt further includes a tray fitted onto the first housing.

[0013] The anchoring method for point weakening and multi-stage negative pressure energy absorption according to the second aspect of the present invention includes:

[0014] An anchoring device is provided, wherein the anchoring device is a fixed-point weakening and multi-stage negative pressure energy absorption anchoring device as described in any of the above embodiments, the weakening section is fixed-point weakened to form a weakening surface, and the second and third sealed rings are located on both sides of the weakening surface.

[0015] Drill holes in the surrounding rock and enlarge the shallow anchoring holes to form a larger diameter, and place the anchoring agent on the anchoring section and the outer wall of the first shell.

[0016] The anchoring device is installed in the anchoring hole, and the anchoring device is rotated to fill the anchoring agent between the anchoring section and the anchoring hole, and between the outer wall of the first shell and the anchoring hole, so that the anchoring section and the anchoring hole are bonded together and the first shell is bonded together with the shallow surrounding rock.

[0017] The negative pressure chamber is depressurized to reduce the pressure inside it, and the positive pressure chamber is pressurized to increase the pressure inside it.

[0018] The anchoring method of fixed-point weakening and multi-stage negative pressure energy absorption in this embodiment of the invention increases the pre-tightening force between the first shell and the anchor hole by pressurizing the positive pressure cavity through the anchoring device of the above embodiment; through the setting of the negative pressure cavity of the anchoring device of the above embodiment, when the surrounding rock deforms, the surrounding rock squeezes the first shell, increasing the pressure in the positive pressure cavity. The first sealed ring moves from the positive pressure cavity to the negative pressure cavity and deforms to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock, reducing the risk of breakage of the pre-tightening section; through the setting of the second energy-absorbing component of the anchoring device of the above embodiment, when the impact force occurs instantaneously, the non-Newtonian fluid is solid to improve the impact resistance; when the stress on the anchor rod is higher than the strength after weakening, the fixed-point weakening point of the weakened section breaks, the second sealed ring and the third sealed ring move towards the end of the second shell and deform to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock, while the second shell and the non-Newtonian fluid continue to play an anchoring role.

[0019] In some embodiments, two digital pressure switches are added to the first housing, one of which is connected to the positive pressure chamber and the other is connected to the negative pressure chamber.

[0020] In some embodiments, pressure control valves are added to both the second and third sealing rings. When the anchor bolt breaks and the second and third sealing rings deform and move toward both ends of the anchor bolt, a non-connected positive pressure zone and a negative pressure zone are simultaneously generated in the second housing. When the pressure in the positive pressure zone is greater than the threshold of the pressure control valve and / or the pressure in the negative pressure zone is less than the threshold of the pressure control valve, the pressure control valve opens to connect the positive pressure zone and the negative pressure zone, so that the non-Newtonian fluid flows to the negative pressure zone.

[0021] In some embodiments, there are multiple weakening surfaces and multiple second energy-absorbing components, and the multiple second energy-absorbing components and the multiple weakening surfaces correspond one-to-one. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the anchoring device for fixed-point weakening and multi-stage negative pressure energy absorption according to an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the anchoring method of fixed-point weakening and multi-stage negative pressure energy absorption according to an embodiment of the present invention.

[0024] Figure label:

[0025] Anchor bolt 1; Pre-tightening section 11; Weakened section 12; Anchoring section 13;

[0026] First energy-absorbing component 2; First housing 21; Positive pressure chamber 211; Negative pressure chamber 212; First sealing ring 22; First pressure switch 23; Second pressure switch 24;

[0027] Second energy-absorbing component 3; second housing 31; second sealing ring 32; third sealing ring 33;

[0028] Tray 4. Detailed Implementation

[0029] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0030] The following describes, in conjunction with the accompanying drawings, an anchoring device for fixed-point weakening and multi-stage negative pressure energy absorption according to an embodiment of the present invention.

[0031] like Figure 1 As shown, the anchoring device for fixed-point weakening and multi-stage negative pressure energy absorption in this embodiment of the invention includes an anchor rod 1, a first energy-absorbing component 2, and a second energy-absorbing component 3.

[0032] Anchor bolt 1 includes a pre-tightening section 11, a weakening section 12 and an anchoring section 13 connected in sequence. The weakening section 12 is weakened at a fixed point to create a weakened surface.

[0033] The first energy-absorbing component 2 includes a first housing 21 and a first sealing ring 22. The first housing 21 is fitted onto the pre-tightening section 11, and the first sealing ring 22 is fitted onto the anchor rod 1 and located inside the first housing 21. The outer peripheral wall of the first sealing ring 22 abuts against the inner peripheral wall of the first housing 21 to divide the internal space of the first housing 21 into a positive pressure chamber 211 and a negative pressure chamber 212. The negative pressure chamber 212 is farther away from the anchoring section 13 relative to the positive pressure chamber 211. It should be noted that after the anchoring device is installed, the pressure in the negative pressure chamber 212 is reduced by depressurizing it, and the pressure in the positive pressure chamber 211 is increased by pressurizing it, thereby ensuring the pre-tightening force of the anchoring system. When the surrounding rock deforms, the first sealing ring 22 and the first housing 21 undergo relative displacement, and the pressure in the positive pressure chamber 211 and the negative pressure chamber 212 changes to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock, reducing the risk of breakage of the pre-tightening section 11.

[0034] The second energy-absorbing component 3 includes a second housing 31, a second sealing ring 32, and a third sealing ring 33. The second housing 31 is fitted onto the weakened section 12. The second sealing ring 32 and the third sealing ring 33 are both fitted onto the anchor rod 1. The outer peripheral walls of the second sealing ring 32 and the third sealing ring 33 abut against the inner peripheral wall of the second housing 31. The second housing 31 is filled with a non-Newtonian fluid. It should be noted that when the impact force occurs instantaneously, the non-Newtonian fluid is solid to improve the impact resistance; when the stress on the anchor rod 1 is higher than the ultimate strength of the weakened section 12 after weakening, the weakened section 12 fractures at the fixed weakening point, the second sealing ring 32 and the third sealing ring 33 move toward the end of the second shell 31 and deform, and the pressure changes at various points in the second shell 31 to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock. At the same time, the second shell 31 and the non-Newtonian fluid continue to play an anchoring role; the second shell 31 blocks the anchoring agent at the anchoring section 13, making the anchoring agent at the anchoring section 13 more compact to increase the anchoring effect of the anchor rod 1.

[0035] The anchoring device of the present invention, which features fixed-point weakening and multi-stage negative pressure energy absorption, increases the pre-tightening force between the first shell 21 and the anchor hole by pressurizing the positive pressure chamber 211. Through the setting of the negative pressure chamber 212, when the surrounding rock deforms, the relative displacement between the first sealed ring 22 and the first shell 21 causes a change in the pressure within the positive pressure chamber 211 and the negative pressure chamber 212, absorbing the energy transferred to the anchoring device by the deformation of the surrounding rock and reducing the risk of breakage of the pre-tightening section 11. Through the setting of the second energy-absorbing component 3, when the impact force occurs instantaneously, the non-Newtonian fluid becomes solid to improve impact resistance. When the stress on the anchor rod 1 is higher than the strength after weakening, the fixed-point weakening point of the weakened section 12 breaks, and the second sealed ring 32 and the third sealed ring 33 move towards the end of the second shell 31 and deform to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock. Simultaneously, the second shell 31 and the non-Newtonian fluid continue to play an anchoring role.

[0036] like Figure 1 As shown, in some embodiments, the first energy-absorbing component 2 further includes a first pressure switch 23 and a second pressure switch 24. The first pressure switch 23 is connected to the first housing 21 and communicates with the negative pressure chamber 212, and the second pressure switch 24 is connected to the first housing 21 and communicates with the positive pressure chamber 211. It can be understood that the first pressure switch 23 is connected to a pressure-reducing device, which uses the first pressure switch 23 to reduce the pressure in the negative pressure chamber 212. The second pressure switch 24 is connected to a pressure-boosting device, which uses the second pressure switch 24 to increase the pressure in the positive pressure chamber 211.

[0037] Furthermore, both the first pressure switch 23 and the second pressure switch 24 are digital display pressure switches. The two digital display pressure switches display the internal pressure of the positive pressure chamber 211 and the negative pressure chamber 212 in real time.

[0038] In some embodiments, pressure control valves (not shown) are provided on both the second sealing ring 32 and the third sealing ring 33. It is understood that after the pressure control valve is set with an opening threshold, when the pressure difference between the two sides of the second sealing ring 32 and / or the third sealing ring 33 exceeds the set threshold, the pressure control valve opens to connect the two sides of the second sealing ring 32 and / or the third sealing ring 33, so that non-Newtonian fluid flows from the positive pressure area to the negative pressure area to regulate the pressure on both sides of the second sealing ring 32 and / or the third sealing ring 33.

[0039] In some embodiments, there are multiple second energy-absorbing components 3, which are distributed at intervals along the axial direction of the anchor bolt 1.

[0040] In some embodiments, the anchor bolt 1 further includes a tray 4, which is fitted onto the first housing 21 and is used to provide preload to the anchor bolt 1.

[0041] The anchoring method for point weakening and multi-stage negative pressure energy absorption according to the second aspect of the present invention includes:

[0042] An anchoring device is provided, which is a fixed-point weakening and multi-stage negative pressure energy absorption anchoring device of any of the above embodiments, to perform fixed-point weakening on the weakened section 12 to form a weakened surface, and to place the second sealing ring 32 and the third sealing ring 33 on both sides of the weakened surface.

[0043] Drill holes in the surrounding rock and enlarge the shallow anchoring holes to form a larger hole diameter, and place the anchoring agent on the outer wall of the anchoring section 13 and the first shell 21.

[0044] The anchoring device is installed in the anchoring hole. The anchoring device is rotated to fill the anchoring agent between the anchoring section 13 and the anchoring hole, and between the outer wall of the first shell 21 and the anchoring hole, so that the anchoring section 13 and the anchoring hole are bonded together and the first shell 21 is bonded together with the shallow surrounding rock.

[0045] The negative pressure chamber 212 is depressurized to reduce the pressure inside the negative pressure chamber 212, and the positive pressure chamber 211 is pressurized to increase the pressure inside the positive pressure chamber 211.

[0046] The anchoring method of fixed-point weakening and multi-stage negative pressure energy absorption in this embodiment of the invention increases the preload between the first shell 21 and the anchor hole by pressurizing the positive pressure chamber 211 through the anchoring device of the above embodiment; through the setting of the negative pressure chamber 212 of the anchoring device of the above embodiment, when the surrounding rock deforms, the surrounding rock squeezes the first shell 21, increasing the pressure in the positive pressure chamber 211. The first sealed ring 22 moves from the positive pressure chamber 211 to the negative pressure chamber 212 and deforms to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock. This reduces the risk of breakage in the pre-tightening section 11. Through the arrangement of the second energy-absorbing component 3 in the anchoring device of the above embodiment, when the impact force occurs instantaneously, the non-Newtonian fluid becomes solid to improve impact resistance. When the stress on the anchor rod 1 exceeds the weakened strength, the weakened section 12 breaks at its fixed weakening point. The second sealing ring 32 and the third sealing ring 33 move towards the end of the second shell 31 and deform to absorb the energy transferred to the anchoring device by the deformation of the surrounding rock. Simultaneously, the second shell 31 and the non-Newtonian fluid continue to play an anchoring role.

[0047] In some embodiments, two digital pressure switches are added to the first housing 21. One digital pressure switch is connected to the positive pressure chamber 211, and the other digital pressure switch is connected to the negative pressure chamber 212. The two digital pressure switches display the pressure in the positive pressure chamber 211 and the negative pressure chamber 212 in real time, respectively.

[0048] In some embodiments, pressure control valves are added to both the second sealing ring 32 and the third sealing ring 33. When the anchor rod 1 breaks and the second sealing ring 32 and the third sealing ring 33 deform and move toward both ends of the anchor rod 1, a non-connected positive pressure zone and a negative pressure zone are simultaneously generated in the second housing 31. When the pressure in the positive pressure zone is greater than the threshold of the pressure control valve and / or the pressure in the negative pressure zone is less than the threshold of the pressure control valve, the pressure control valve opens to connect the positive pressure zone and the negative pressure zone, so that the non-Newtonian fluid flows to the negative pressure zone, thereby adjusting the pressure difference on both sides of the second sealing ring 32 and / or the third sealing ring 33.

[0049] In some embodiments, there are multiple weakening surfaces and multiple second energy-absorbing components 3, and the multiple second energy-absorbing components 3 correspond one-to-one with the multiple weakening surfaces.

[0050] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, 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. Therefore, they should not be construed as limitations on this invention.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0052] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0053] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0054] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0055] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A spot-weakened and multi-stage negative pressure energy-absorbing anchoring device, characterized by, The anchor rod comprises a pre-tightening section, a weakening section and an anchoring section connected in sequence; The first energy-absorbing assembly comprises a first shell and a first closed ring, the first shell is sleeved on the pre-tightening section, the first closed ring is sleeved on the anchor rod and located in the first shell, the outer peripheral wall of the first closed ring abuts against the inner peripheral wall of the first shell to divide the inner space of the first shell into a positive pressure cavity and a negative pressure cavity, the negative pressure cavity is away from the anchoring section relative to the positive pressure cavity; The second energy-absorbing assembly comprises a second shell, a second closed ring and a third closed ring, the second shell is sleeved on the weakening section, the second closed ring and the third closed ring are both sleeved on the anchor rod, and the outer peripheral wall of the second closed ring and the outer peripheral wall of the third closed ring both abut against the inner peripheral wall of the second shell, and the second shell is filled with a non-Newtonian fluid. The first energy-absorbing assembly further comprises a first pressure switch and a second pressure switch, the first pressure switch is connected to the first shell and communicates with the negative pressure cavity, and the second pressure switch is connected to the first shell and communicates with the positive pressure cavity.

2. The spot-weakened and multi-stage negative pressure energy-absorbing anchoring device of claim 1, wherein, Both the first pressure switch and the second pressure switch are digital pressure switches.

3. The spot-weakened and multi-stage negative pressure energy-absorbing anchoring device of claim 2, wherein, Both the second closed ring and the third closed ring are provided with a pressure control valve.

4. The spot-weakened and multi-stage negative pressure energy-absorbing anchoring device of claim 1, wherein, There are multiple second energy-absorbing assemblies, and the multiple second energy-absorbing assemblies are distributed along the axial direction of the anchor rod.

5. The spot-weakened and multi-stage negative pressure energy-absorbing anchoring device of claim 1, wherein, The anchor rod further comprises a tray, and the tray is sleeved on the first shell.

6. The spot-weakened and multi-stage negative pressure energy absorbing anchoring device of claim 1, wherein, The anchor device is provided, and the anchor device is the anchor device for spot weakening and multi-stage negative pressure energy absorption according to any one of claims 1-6, the weakening section is spot weakened to form a weakening surface, and the second closed ring and the third closed ring are located on both sides of the weakening surface; 7. A method of anchoring by site weakening and multi-stage negative pressure energy absorption, characterized by, The surrounding rock is drilled and the shallow anchor hole is reamed to form a larger hole diameter, and the anchor agent is placed on the outer wall of the first shell and the anchoring section; The anchor device is installed in the anchor hole, the anchor device is rotated to fill the anchor agent between the anchoring section and the anchor hole and between the outer wall of the first shell and the anchor hole, the anchoring section and the anchor hole are bonded to be integrated, and the first shell and the shallow surrounding rock are bonded to be integrated; The negative pressure cavity is pumped to reduce the pressure in the negative pressure cavity, and the positive pressure cavity is pressurized to increase the pressure in the positive pressure cavity. Two digital pressure switches are additionally provided on the first shell, one of the digital pressure switches communicates with the positive pressure cavity, and the other digital pressure switch communicates with the negative pressure cavity. Pressure control valves are additionally provided on the second closed ring and the third closed ring, when the anchor rod is broken and the second closed ring and the third closed ring are deformed and move to both ends of the anchor rod, the second shell simultaneously generates a non-communicating positive pressure area and a negative pressure area, when the pressure of the positive pressure area is greater than the threshold value of the pressure control valve and / or the pressure of the negative pressure area is less than the threshold value of the pressure control valve, the pressure control valve is opened to make the positive pressure area and the negative pressure area communicate, so that the non-Newtonian fluid flows to the negative pressure area.

8. The method of spot-weakening and multi-stage negative pressure energy absorption anchorage of claim 7, wherein, ​ 9. The method of spot-weakening and multi-stage negative pressure energy- absorbing anchoring of claim 7, wherein, ​ 10. The method of spot-weakening and multi-stage negative pressure energy- absorbing anchorage of claim 7, wherein, The weakening surfaces and the second energy-absorbing components are provided in plurality, and the plurality of second energy-absorbing components and the plurality of weakening surfaces are in one-to-one correspondence.

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