Nuclear power foundation anchoring device

Abstract

The present disclosure provides a nuclear power foundation anchoring device, comprising an anchor rod, a sleeve and a reset assembly, the anchor rod is arranged in the anchor hole of the rock wall, the sleeve is arranged outside the anchor rod and is fixedly installed on the rock wall; the reset assembly is provided with at least one reset unit along the axial direction of the anchor rod, the reset unit comprises a first mounting rod, a second mounting rod, a first elastic member and a second elastic member, the first mounting rod, the second mounting rod, the first elastic member and the second elastic member are installed in the sleeve and are arranged outside the anchor rod; the axial two ends of the first elastic member are elastically connected with the first mounting rod and the second mounting rod respectively, the second elastic member is arranged outside the first mounting rod, the first elastic member and the second mounting rod, the first elastic member and the second elastic member are coaxially arranged; wherein, the inner side of the first mounting rod is provided with a mounting groove, and the anchor rod is fixedly provided with a mounting block embedded in the mounting groove.

Description

Technical Field

[0001] This disclosure relates to the field of nuclear power plant foundation pit anchoring technology, and in particular to a nuclear power plant foundation pit anchoring device. Background Technology

[0002] In nuclear power plant foundation pit and high slope support engineering, prestressed anchor bolts are the core load-bearing components that ensure the stability of the surrounding rock of the foundation pit.

[0003] Traditional anchor bolts typically employ a full-length bonded or tension-type structure, where the anchor bolt is integrally bonded to the surrounding rock anchor hole wall through grouting, relying on the tensile strength of the anchor bolt itself and the frictional resistance of the surrounding rock to provide support.

[0004] However, under seismic loads or long-term creep of the surrounding rock, the surrounding rock will undergo irreversible deformation and displacement. Traditional anchor bolts, lacking a yielding and reset mechanism, will either yield and fracture due to rigid resistance or lose preload due to plastic elongation. After an earthquake, the anchor bolts cannot return to their initial working position, and the support capacity will be drastically reduced, making it difficult to meet the stringent requirements for long-term seismic stability of nuclear power plant pits.

[0005] Based on this, this disclosure proposes a nuclear power plant foundation pit anchoring device in order to solve one or more of the above-mentioned technical problems. Summary of the Invention

[0006] This disclosure solves the above-mentioned technical problems through the following technical solution: The purpose of this disclosure is to provide a nuclear power plant foundation pit anchoring device.

[0007] According to the first aspect of this disclosure, the nuclear power plant foundation pit anchoring device includes: an anchor rod, a sleeve and a reset assembly, wherein the anchor rod is inserted into an anchor hole opened in the rock wall, and the sleeve is sleeved on the outside of the anchor rod and fixedly installed on the rock wall; The reset assembly is provided with at least one reset unit along the axial direction of the anchor rod. The reset unit includes a first mounting rod, a second mounting rod, a first elastic element, and a second elastic element. The first mounting rod, the second mounting rod, the first elastic element, and the second elastic element are installed in the sleeve and sleeved on the outside of the anchor rod. The first elastic element is elastically connected to the first mounting rod and the second mounting rod at its two axial ends, respectively. The second elastic element is sleeved on the outside of the first mounting rod, the first elastic element and the second mounting rod. The first elastic element and the second elastic element are coaxially arranged. The first mounting rod has an inner groove, and the anchor rod has a mounting block embedded in the mounting groove.

[0008] The technical solution described above, by setting a reset unit arranged along the axial direction of the anchor rod inside the sleeve, and utilizing the structure of the first elastic element and the second elastic element coaxially stacked, allows the first elastic element to bear high-frequency impact loads on the inner side and provide high-rigidity anti-relaxation reset force, while the second elastic element is sleeved on the outer side to bear large-stroke deformation to adapt to low-frequency creep displacement of the surrounding rock. The two work together to achieve automatic reset of the anchor rod after the earthquake and reduce permanent residual deformation, avoiding the problem of fatigue or crushing of a single elastic element under frequent vibration.

[0009] In one or more embodiments, the first elastic element is a disc spring, which includes a plurality of coaxially stacked disc springs.

[0010] In one or more embodiments, the second elastic element is a helical compression spring.

[0011] In one or more embodiments, the first mounting rod is provided with a first baffle on the side opposite to the second mounting rod, and the second mounting rod is provided with a second baffle on the side opposite to the first mounting rod; The two ends of the second elastic element elastically abut against the first baffle and the second baffle, respectively.

[0012] In one or more embodiments, the reset assembly is provided with at least two reset units along the axial direction of the anchor rod, and a fixing seat is provided between adjacent reset units. The fixing seat is sleeved on the outside of the anchor rod and positioned at the target position of the anchor rod. The fixed seat is annular, and its outer peripheral wall is provided with multiple balls, which roll and abut against the inner wall of the sleeve.

[0013] In one or more embodiments, a connecting flange is provided on the outside of the sleeve, one end of the reset assembly extends to the bottom of the sleeve, and the other end is provided with a stop plate, and the second elastic element of the reset unit near the outside of the anchor hole abuts against the stop plate; The anchoring device also includes a support component, which includes a housing with a mating flange. The housing is anchored to the rock wall by a plurality of threaded connectors that pass through the mating flange, the stop plate and the connecting flange in sequence to be fixedly connected to the rock wall.

[0014] In one or more embodiments, the connecting flange is further provided with an extension cylinder on the side opposite to the reset unit, and the support member further includes a mounting bracket and a connector, both of which are located inside the housing; The mounting bracket is fitted onto the outside of the extension tube and fixedly connected to the outer shell, and the connector is threadedly connected to the mounting bracket.

[0015] In one or more embodiments, the mounting bracket has an elastic ring on the side opposite to the reset assembly, and the inner wall of the elastic ring abuts against the outer wall of the extension cylinder.

[0016] In one or more embodiments, the elastic ring is fixed to the mounting bracket and sleeved on the outside of the extension cylinder, and the elastic ring includes a plurality of spaced-apart snap-fit ​​blocks, which elastically retract inward toward the axial direction of the extension cylinder.

[0017] In one or more embodiments, the connector has an internal bevel, which, when the connector is screwed into the mounting bracket, presses against the snap-fit ​​block to cause the elastic ring to elastically press against the outer wall of the extension cylinder. Attached Figure Description

[0018] The above and other features, properties and advantages of this disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, wherein: Figure 1 This is a schematic diagram of the overall structure of a nuclear power plant foundation pit anchoring device according to an embodiment of the present disclosure; Figure 2 for Figure 1 A schematic diagram of the internal structure of the anchoring device for the foundation pit of China Nuclear Power Plant at one angle; Figure 3 for Figure 2 Enlarged schematic diagram of part of the structure; Figure 4 for Figure 3 A schematic diagram of the exploded structure; Figure 5 for Figure 4 A partial structural breakdown diagram; Figure 6 This is a schematic diagram of the internal structure of a support member at one angle according to an embodiment of the present disclosure; Figure 7 for Figure 6 A schematic diagram of the explosion structure.

[0019] 1. Anchor bolt; 11. Mounting block; 12. Positioning groove; 2. Sleeve; 21. Connecting flange; 22. Extension sleeve; 3. Reset assembly; 31. Stop plate; 4. Rock face; 41. Anchor hole; 42. Limiting hole; 5. Reset unit; 51. First mounting rod; 511. Mounting groove; 512. First baffle; 52. Second mounting rod; 521. Second baffle; 53. First elastic element; 54. Second elastic element; 55. Fixed seat; 551. Ball bearing; 552. Limiting groove; 56. Limiting ring; 561. Limiting post; 6. Support components; 61. Housing; 62. Fitting flange; 63. Mounting bracket; 64. Connecting component; 641. Inclined surface; 65. Elastic ring; 651. Snap-fit ​​block. Detailed Implementation

[0020] The present disclosure will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present disclosure. However, the present disclosure can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present disclosure. Therefore, the scope of protection of the present disclosure should not be limited by the content of this specific embodiment.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure; the terms “comprising” and “having”, and any variations thereof, in the specification, claims and foregoing description of the drawings of this disclosure are intended to cover non-exclusive inclusion.

[0022] It should be noted that the nuclear power plant foundation pit anchoring device described in the following embodiments is mainly used in the prestressed anchor system in the foundation pit and high slope support engineering of nuclear power plants. However, the anchoring device proposed in this disclosure can also be applied to other geotechnical engineering anchoring fields that require seismic self-resetting function, such as tunnel support, slope reinforcement, water conservancy dam foundation, underground cavern and other projects, as long as it is necessary to ensure that the anchor can automatically reset and continuously provide support force after earthquake or surrounding rock deformation in these projects.

[0023] In this disclosure, the term axial refers to the direction along the length of the anchor bolt 1, and the terms radial or transverse refer to the direction perpendicular to the axis of the anchor bolt 1.

[0024] Figure 1 A schematic diagram of the overall structure of a nuclear power plant foundation pit anchoring device according to an embodiment of the present disclosure is shown. Figure 1 As shown, an embodiment of the nuclear power plant pit anchoring device disclosed herein includes at least an anchor rod 1, a sleeve 2, and a reset assembly 3.

[0025] Anchor bolt 1 is inserted into the anchor hole 41 opened in the rock wall 4. Here, anchor bolt 1 refers to a rod-shaped load-bearing component inserted into the anchor hole 41 in the rock wall 4 and used to anchor the surrounding rock to the support structure. The specific structural form is not limited here. For example, it may include threaded steel anchor bolts, seamless steel pipe anchor bolts, fiberglass anchor bolts, etc., and its length, diameter, material, and other parameters can be selected according to specific engineering design requirements.

[0026] Specifically, one end of the anchor rod 1 is embedded inside the rock wall 4, and the other end extends to the outside of the anchor hole 41 and connects to the reset assembly 3 inside the sleeve 2. A limiting hole 42 communicating with the anchor hole 41 is provided on the outlet side of the anchor hole 41, and the main body of the reset assembly 3 is embedded in the limiting hole 42.

[0027] Because the anchor rod 1 will displace along its axial direction during an earthquake or deformation of the surrounding rock, this disclosure provides a reset component 3, which can absorb the load of the anchor rod 1 deformation and drive the anchor rod 1 to rebound to the initial position after the load disappears.

[0028] Please refer to Figure 2 and Figure 3 The sleeve 2 is fitted onto the outside of the anchor rod 1 and fixedly installed on the rock wall 4. Specifically, the sleeve 2 is embedded in the limiting hole 42 and fixedly installed on the rock wall 4.

[0029] It should be noted that the sleeve 2 refers to the cylindrical structure that is sleeved on the outside of the anchor rod 1 and fixedly installed on the rock wall 4. Its function is to provide installation space and guide channel for the reset assembly 3, so that the anchor rod 1 can slide axially within the sleeve 2 without radial displacement. The cross-sectional shape of the sleeve 2 can be circular, rectangular, etc., and its material can be steel pipe, alloy pipe, etc., without limitation.

[0030] Optionally, the fixing method between the sleeve 2 and the rock wall 4 may include grouting fixing or mechanical expansion shell fixing.

[0031] If the sleeve 2 is fixed to the rock wall 4 by grouting, high-strength non-shrink grout can be injected into the annular gap between the sleeve 2 and the wall of the anchor hole 41 to make the sleeve 2 and the rock wall 4 form an integral anchor.

[0032] Alternatively, the sleeve 2 can be fixed to the rock wall 4 by mechanical expansion.

[0033] Furthermore, the outer wall of sleeve 2 can also be provided with an anti-corrosion coating (not shown in the figure) to adapt to the long-term corrosive environment of the nuclear power plant pit.

[0034] like Figure 3 and Figure 4 As shown, the reset assembly 3 is installed inside the sleeve 2 and sleeved on the outside of the anchor rod 1.

[0035] Specifically, the reset component 3 is an elastic reset device installed inside the sleeve 2 and sleeved on the outside of the anchor rod 1. Its function is to absorb energy and store elastic potential energy under the action of earthquake or surrounding rock deformation load, and release the elastic potential energy after the load disappears to drive the anchor rod 1 to rebound to the initial position.

[0036] Optionally, the reset assembly 3 is provided with at least one reset unit 5 along the axial direction of the anchor rod 1 to accommodate the requirements of different seismic resistance levels. For example... Figures 2 to 4As shown, the reset assembly 3 is provided with two reset units 5 along the axial direction of the anchor rod 1. However, this is just an example and the number of reset units 5 is not limited. In actual application, the number of reset units 5 can be set according to actual needs.

[0037] Please refer to Figure 4 and Figure 5 Each reset unit 5 includes a first mounting rod 51, a second mounting rod 52, a first elastic element 53, and a second elastic element 54. All of the above components are installed inside the sleeve 2 and sleeved on the outside of the anchor rod 1.

[0038] Specifically, in each reset unit 5, the first elastic member 53 is elastically connected to the first mounting rod 51 and the second mounting rod 52 at its two axial ends.

[0039] The first mounting rod 51 and the second mounting rod 52 refer to the hollow rod-shaped structures in the reset unit 5 used for mounting and supporting the elastic element, and they are arranged opposite each other along the axial direction of the anchor rod 1. The two ends of the first elastic element 53 are elastically connected to the side of the first mounting rod 51 facing the second mounting rod 52 and the side of the second mounting rod 52 facing the first mounting rod 51, respectively. The cross-sectional shape of the mounting rod is not limited here, and may include, for example, circular rings, square rings, etc., and its material may include alloy steel, carbon steel, etc., which is also not limited here.

[0040] The second elastic element 54 is sleeved on the outside of the first mounting rod 51, the first elastic element 53, and the second mounting rod 52. The first elastic element 53 and the second elastic element 54 are coaxially arranged, and the first elastic element 53 is located inside the second elastic element 54.

[0041] Specifically, the first elastic element 53 and the second elastic element 54 refer to the elastic elements in the reset unit 5 that provide elastic reset force. The first elastic element 53 is located on the inner side and is mainly used to bear high-frequency impact loads and provide high stiffness anti-relaxation reset force. The second elastic element 54 is located on the outer side and is mainly used to bear large stroke deformation to adapt to low-frequency surrounding rock creep displacement. The two are coaxially stacked to achieve collaborative work.

[0042] This coaxial composite structure enables the first elastic element 53 and the second elastic element 54 to work collaboratively during axial compression. Specifically, when subjected to high-frequency impact loads, the first elastic element 53, with its high stiffness, bears the impact first and provides restoring force. When subjected to low-frequency large-displacement loads, the second elastic element 54, with its large stroke characteristics, undertakes the main deformation. Both store elastic potential energy together, and release the potential energy simultaneously after the load disappears to drive the anchor rod 1 back to its initial position, achieving self-resetting.

[0043] It is particularly important to note that in the seismic support of nuclear power plant foundation pits, seismic loads typically include a superposition of high-frequency short-time impact components and low-frequency long-time displacement components. A single elastic element cannot simultaneously meet the dual requirements of high stiffness and relaxation resistance as well as large stroke deformation. Therefore, this disclosure achieves dual-frequency elastic response without increasing the radial dimension by coaxially stacking the first elastic element 53 and the second elastic element 54, effectively solving the problem of fatigue or crushing of a single elastic element.

[0044] Please continue to refer to Figure 4 and Figure 5 An installation groove 511 is provided on the inner side of the first mounting rod 51. The radial dimension of the installation groove 511 is larger than the radial dimension of the anchor rod 1. An installation block 11 is fixed on the anchor rod 1 and embedded in the installation groove 511. The size of the installation block 11 corresponds to the size of the installation groove 511. The circumferential positioning and axial sliding limit between the anchor rod 1 and the first mounting rod 51 can be achieved through the fitting of the two.

[0045] Specifically, when the anchor rod 1 is subjected to axial force and slides along the sleeve 2, the mounting block 11 slides accordingly within the mounting groove 511. The sliding of the mounting block 11 causes the first elastic element 53 to repeatedly compress and rebound. If the mounting block 11 moves to the bottom of the mounting groove 511 (near the anchor hole 41), the continued movement of the mounting block 11 will compress the second elastic element 54 through the first baffle 512 (see below), causing the second elastic element 54 to also be compressed.

[0046] The length of the mounting groove 511 limits the maximum sliding stroke of the mounting block 11, thereby limiting the maximum compression stroke of the reset unit 5, which can prevent the first elastic element 53 and the second elastic element 54 from being over-compressed and crushed.

[0047] According to a preferred embodiment of this disclosure, such as Figure 4 and Figure 5 As shown, the first elastic element 53 is a disc spring. A disc spring is a combined elastic element composed of several single disc springs coaxially stacked together. The disc spring has a truncated conical shell structure, and it bears axial loads and stores elastic potential energy through the elastic deformation of the disc spring plates. Disc springs have high stiffness and resistance to stress relaxation, and can withstand high-frequency short-term impact loads. Multiple disc springs can be combined by means of parallel stacking, overlapping stacking, or composite stacking.

[0048] Optionally, multiple disc springs can be coaxially stacked, meaning the central axes of all disc springs coincide and the convex surfaces of adjacent disc springs in the same direction are stacked together to obtain the required combined stiffness and load-bearing capacity. The number of disc springs and the stacking method can be selected according to the seismic requirements of the project, but this is not a limitation.

[0049] Optionally, the second elastic element 54 is a helical compression spring. A helical compression spring bears axial compressive loads and stores elastic potential energy through the torsional deformation of its spring wire. It features a large deformation stroke and good linear stiffness characteristics, making it suitable for handling low-frequency, large-displacement elastic deformation. The helical compression spring is made by winding spring wire along a helical line. Its parameters, such as the spring wire diameter, spring mean diameter, and effective number of turns, can be designed according to the required spring stiffness and stroke. The helical compression spring is fitted onto the outside of the disc spring, meaning the inner diameter of the helical compression spring is larger than the maximum outer diameter of the stacked disc springs. This allows the disc spring to be freely accommodated inside the helical compression spring without interference.

[0050] According to another preferred embodiment of this disclosure, such as Figure 4 and Figure 5 As shown, the first mounting rod 51 has a first baffle 512 on the side opposite to the second mounting rod 52, and the second mounting rod 52 has a second baffle 521 on the side opposite to the first mounting rod 51. The function of the first baffle 512 and the second baffle 521 is to provide elastic contact surfaces for the axial ends of the second elastic member 54.

[0051] The second elastic element 54 elastically abuts against the first baffle 512 and the second baffle 521 at its two axial ends, respectively. When the reset unit 5 is subjected to axial compression, the second elastic element 54 is compressed between the first baffle 512 and the second baffle 521, storing elastic potential energy. When the axial load disappears, the second elastic element 54 releases its potential energy, pushing the first baffle 512 and the second baffle 521 away from each other, thereby driving the anchor rod 1 to rebound.

[0052] The first baffle 512 and the second baffle 521 can be integrally formed with the first mounting rod 51 and the second mounting rod 52, or they can be fixed to the mounting rod by welding, bolt connection or other means, which is not limited here.

[0053] Please continue to refer to Figure 4 and Figure 5 The reset assembly 3 is provided with at least two reset units 5 along the axial direction of the anchor rod 1. A fixing seat 55 is provided between adjacent reset units 5. The fixing seat 55 is sleeved on the outside of the anchor rod 1 and positioned at the target position of the anchor rod 1.

[0054] The fixed seat 55 is annular, and its outer peripheral wall is provided with multiple balls 551, which roll and abut against the inner wall of the sleeve 2.

[0055] Optionally, the anchor rod 1 is provided with a positioning groove 12, and the fixing seat 55 is sleeved on the outside of the positioning groove 12 and positioned and cooperates with the anchor rod 1. That is, the position of the positioning groove 12 is the target position of the fixing seat 55 on the anchor rod 1.

[0056] It should be noted that if the reset assembly 3 includes at least two reset units 5, a fixing seat 55 will be provided between adjacent reset units 5. Moreover, the fixing seat 55 has multiple limiting grooves 552 on both axially opposite sides, and a limiting ring 56 is provided on the side of the first baffle 512 or the second baffle 521 facing the fixing seat 55. The limiting ring 56 is provided with a limiting post 561 that is adapted to the limiting groove 552.

[0057] It should be noted that the function of the fixed seat 55 is to provide axial positioning and separation for adjacent reset units 5, and at the same time, the ball bearings 551 reduce the frictional resistance when the reset assembly 3 slides in the sleeve 2.

[0058] The ball 551 is rotatably connected to the outer peripheral wall of the fixed seat 55, and the outer surface of the ball 551 is in rolling contact with the inner wall of the sleeve 2.

[0059] Optionally, the ball 551 can be made of high-strength alloy steel to withstand the contact compressive stress on the inner wall of the sleeve 2 and maintain long-term wear resistance.

[0060] When the reset assembly 3 slides axially within the sleeve 2 along with the anchor rod 1, the balls 551 rotate on the fixed seat 55 and generate rolling friction with the inner wall of the sleeve 2. By significantly reducing the original sliding friction to rolling friction, the resistance during the reset process of the anchor rod 1 can be reduced, ensuring the reliability and sensitivity of the self-reset. The number of balls 551 can be set according to the outer circumferential dimensions of the fixed seat 55; for example, 6 to 12 balls 551 can be evenly distributed along the outer circumferential wall of the fixed seat 55, and no limitation is made here.

[0061] Please refer to Figure 6 and Figure 7 The sleeve 2 is provided with a connecting flange 21 on its outer side. The function of the connecting flange 21 is to provide a flange connection interface between the sleeve 2 and the support 6, so that the sleeve 2 and the support 6 can be detachably and sealedly connected by fasteners such as bolts.

[0062] Specifically, the connecting flange 21 can be integrally formed with the sleeve 2, or it can be fixed to the outer peripheral wall of the sleeve 2 by welding or other means, which is not limited here.

[0063] One end of the reset assembly 3 extends to the bottom of the sleeve 2, and the other end is provided with a stop plate 31. The function of the stop plate 31 is to provide an axial abutment surface for the second elastic element 54 of the reset unit 5 near the outside of the anchor hole 41.

[0064] Specifically, one end of the second elastic element 54 of the reset unit 5 near the outside of the anchor hole 41 elastically abuts against the second baffle 521 of the reset unit 5, and the other end abuts against the stop plate 31. The stop plate 31 is fixed to the sleeve 2 or the support member 6. When the second elastic element 54 is axially compressed, the stop plate 31 bears the axial reaction force of the second elastic element 54 and provides a fixed support end for the second elastic element 54.

[0065] Further reference Figure 6 and Figure 7 The anchoring device also includes support components 6.

[0066] Specifically, the support member 6 includes a housing 61, on which a mating flange 62 is provided. The housing 61 is anchored to the rock wall 4 by a plurality of threaded connectors passing through the mating flange 62, the stop plate 31 and the connecting flange 21 in sequence, so as to be fixedly connected to the rock wall 4.

[0067] The function of the support component 6 is to seal the opening end of the sleeve 2 from the outside of the anchor hole 41, and to anchor the sleeve 2, the stop plate 31 and the support component 6 in series to the rock wall 4 through the flange connection structure.

[0068] Specifically, the threaded connector can be a high-strength bolt, which passes through the mating flange 62 on the outer shell 61 of the support member 6, the stop plate 31 and the connecting flange 21 on the sleeve 2 in sequence, and finally anchors into the rock wall 4 to a predetermined depth, so that the support member 6, the stop plate 31 and the sleeve 2 form an integral anchoring structure.

[0069] The number of threaded connectors can be selected according to the flange size and anchoring force requirements. For example, 4 to 8 bolts can be evenly distributed along the flange circumference. The specific number is not limited here.

[0070] Please continue to refer to Figure 7 An extension cylinder 22 is also provided on the side of the connecting flange 21 opposite to the reset unit 5. The extension cylinder 22 is fixed to the connecting flange 21, and its inner diameter is larger than the outer diameter of the anchor rod 1, so that the anchor rod 1 can pass through the center of the extension cylinder 22 without contacting the inner wall of the extension cylinder 22. The function of the extension cylinder 22 is to provide an installation reference and radial constraint object for the stabilizing components on its outer side.

[0071] Furthermore, the support component 6 also includes a mounting bracket 63 and a connector 64. Both the mounting bracket 63 and the connector 64 are located inside the housing 61. The mounting bracket 63 is fitted onto the outside of the extension tube 22 and is fixedly connected to the housing 61, and the connector 64 is threadedly connected to the mounting bracket 63.

[0072] The mounting bracket 63 serves to provide a mounting base for the elastic ring 65 and the connector 64. The mounting bracket 63 has a ring-shaped structure and is fitted onto the outside of the extension tube 22, allowing the extension tube 22 to pass through the center of the mounting bracket 63. The fixed connection between the mounting bracket 63 and the outer shell 61 can be achieved by bolting, welding, snap-fitting, etc., and is not limited here.

[0073] The function of the connector 64 is to adjust the tightness of the elastic ring 65 on the extension cylinder 22 by screwing it in. The threaded connection between the connector 64 and the mounting bracket 63 can be made by using internal and external threads. For example, the mounting bracket 63 has external threads on the outside and the connector 64 has internal threads on the inside. The connector 64 and the mounting bracket 63 are threadedly fastened together.

[0074] Furthermore, an elastic ring 65 is provided on the side of the mounting bracket 63 opposite to the reset assembly 3. The inner wall of the elastic ring 65 presses against the outer wall of the extension cylinder 22.

[0075] The function of the elastic ring 65 is to apply radial clamping force to the extension cylinder 22 to suppress the lateral vibration and eccentric bending moment generated by the anchor bolt 1 during earthquakes or surrounding rock deformation. The elastic ring 65 can be made of elastic materials such as rubber or polyurethane, and its inner wall maintains an elastic contact with the outer wall of the extension cylinder 22.

[0076] When the anchor rod 1 is subjected to a lateral vibration load, the extension cylinder 22 will have a tendency to lateral displacement. The elastic ring 65 applies a radial elastic constraint force to the extension cylinder 22 through its inner wall, which can suppress the lateral displacement of the extension cylinder 22, thereby limiting the lateral sway of the anchor rod 1 and preventing the anchor rod 1 from getting stuck with the inner wall of the sleeve 2 due to eccentric contact.

[0077] In one embodiment, the elastic ring 65 is fixed to the mounting bracket 63 and sleeved on the outside of the extension cylinder 22, and the elastic ring 65 includes a plurality of spaced-apart snap-fit ​​blocks 651. The snap-fit ​​blocks 651 elastically retract inward toward the axial direction of the extension cylinder 22.

[0078] Multiple snap-fit ​​blocks 651 are distributed circumferentially along the mounting frame 63. One end of each snap-fit ​​block 651 is fixed to the mounting frame 63, and the other end extends toward the axis of the extension cylinder 22 and elastically presses against the outer wall of the extension cylinder 22.

[0079] Optionally, the snap-fit ​​block 651 can be integrally molded onto the mounting bracket 63 using an elastic material, or it can be fixed onto the mounting bracket 63 as an independent component; no limitation is made here.

[0080] That is, the spaced distribution of the snap-fit ​​blocks 651 allows each snap-fit ​​block 651 to independently apply radial elastic force to the extension cylinder 22. When the extension cylinder 22 undergoes eccentric displacement, the snap-fit ​​block 651 on the offset side is further compressed to increase the resistance force, while the snap-fit ​​block 651 on the opposite side is appropriately loosened, thereby forming an adaptive radial constraint force distribution, so that the extension cylinder 22 can be uniformly elastically tightened under various eccentric states.

[0081] Furthermore, the connector 64 has an internal bevel 641. When the connector 64 is screwed into the mounting bracket 63, the bevel 641 presses against the locking block 651, so that the elastic ring 65 elastically presses against the outer wall of the extension cylinder 22.

[0082] The inclined surface 641 is located on the inner wall surface of the connector 64 in contact with the locking block 651. When the connector 64 is screwed into the mounting bracket 63 along the thread, the inclined surface 641 gradually penetrates and contacts the outer surface of the locking block 651. The wedge-shaped structure of the inclined surface 641 converts the axial screwing motion of the connector 64 into a radial compression motion on the locking block 651, causing the locking block 651 to elastically retract inward toward the axis of the extension cylinder 22, increasing the pressure of the elastic ring 65 against the outer wall of the extension cylinder 22. By adjusting the screwing depth of the connector 64, the clamping force of the elastic ring 65 on the extension cylinder 22 can be precisely controlled, ensuring that the clamping force is sufficient to suppress the lateral vibration of the anchor rod 1, while not being too large to hinder the axial sliding of the anchor rod 1. This adjustable clamping mechanism allows the anchoring device to adapt to engineering needs under different seismic resistance levels and geological conditions.

[0083] The following is combined with Figures 1 to 7 The working principle of a nuclear power plant foundation pit anchoring device according to an embodiment of this disclosure is described below: Under normal operating conditions, the anchor rod 1 is inserted into the anchor hole 41 of the rock wall 4, the sleeve 2 is fixedly installed on the rock wall 4, and the reset assembly 3 is installed inside the sleeve 2 and is in a pre-compressed state, providing initial preload to the anchor rod 1. The first elastic element 53 and the second elastic element 54 are coaxially stacked to maintain the axial preload of the anchor rod 1. The elastic ring 65 elastically presses against the outer wall of the extension cylinder 22 through the snap-fit ​​block 651, applying radial constraint to the anchor rod 1.

[0084] When an earthquake or surrounding rock deformation occurs, the rock wall 4 displaces, and the anchor rod 1 is subjected to axial force. When the axial force overcomes the preload of the reset assembly 3, the anchor rod 1 slides axially along the sleeve 2. The axial sliding of the anchor rod 1 will sequentially compress the first elastic element 53 and the second elastic element 54, both of which store elastic potential energy. Among them, the first elastic element 53 (disc spring) first bears the high-frequency impact load due to its high stiffness, while the second elastic element 54 (coil compression spring) bears the low-frequency large displacement deformation due to its large stroke characteristics. The two work together to avoid fatigue or crushing of a single elastic element due to overload.

[0085] While the anchor rod 1 is subjected to axial force, it may also experience lateral vibration and eccentric bending moment. At this time, the extension cylinder 22 will exhibit a tendency for lateral displacement. The locking block 651 of the elastic ring 65 applies a radial elastic constraint force to the outer wall of the extension cylinder 22, thereby suppressing the lateral displacement of the extension cylinder 22 and preventing the anchor rod 1 from getting stuck between it and the inner wall of the sleeve 2 due to eccentric contact, ensuring that the anchor rod 1 can smoothly slide axially within the sleeve 2. By adjusting the screw-in depth of the connector 64, the clamping force of the elastic ring 65 on the extension cylinder 22 can be controlled, effectively suppressing lateral vibration without hindering axial sliding.

[0086] When the seismic load or surrounding rock deformation load disappears, the first elastic element 53 and the second elastic element 54 release their stored elastic potential energy, which can push the first mounting rod 51 and the second mounting rod 52 away from each other, causing the anchor rod 1 to slide back to its initial position and achieve self-resetting. Because the first elastic element 53 (disc spring) has excellent stress relaxation resistance, it can still maintain sufficient restoring force after frequent vibrations, ensuring that the anchor rod 1 can reliably rebound after multiple seismic cycles and continue to provide support force.

[0087] In one embodiment, the construction method for the nuclear power plant foundation pit anchoring device includes the following steps: First, anchor holes 41 are drilled in the rock wall 4. After cleaning the holes, the sleeve 2 is inserted into the anchor holes 41 to the designed depth (corresponding to insertion into the limiting hole 42). The diameter of the limiting hole 42 can be 20-30 mm larger than the outer diameter of the sleeve 2 to allow space for grouting. However, the difference between the diameter of the limiting hole 42 and the sleeve 2 can be adjusted according to the specific grouting process and rock wall conditions, and is not limited here.

[0088] Then, the first mounting rod 51, the second mounting rod 52, the first elastic element 53, and the second elastic element 54 of the reset assembly 3 are assembled inside the sleeve 2 and fitted onto the outside of the anchor rod 1, wherein the mounting groove 511 on the inner side of the first mounting rod 51 engages and is positioned with the mounting block 11 on the anchor rod 1. When multiple reset units 5 are provided, the fixing seat 55 between adjacent reset units 5 is fitted onto the outside of the anchor rod 1, ensuring that the ball bearing 551 makes rolling contact with the inner wall of the sleeve 2.

[0089] Next, the sleeve 2 is fixed to the wall of the anchor hole 41 by grouting or mechanical expansion, and the support 6 is fixed to the rock wall 4 by bolts.

[0090] Then, place the extension cylinder 22 on the connecting flange 21 into the mounting bracket 63, install the elastic ring 65 into the mounting bracket 63 and screw it into the connector 64, so that the inclined surface 641 inside the connector 64 presses the snap block 651 of the elastic ring 65, so that the elastic ring 65 hugs the extension cylinder 22.

[0091] Finally, the screwing amount of the connector 64 is adjusted to control the clamping force of the elastic ring 65 on the extension cylinder 22, so that the clamping force can suppress the lateral vibration of the anchor rod 1 without hindering the axial sliding of the anchor rod 1.

[0092] Although various embodiments of this disclosure are described in the accompanying drawings with reference to structural examples of nuclear power plant foundation pit anchoring devices, it should be understood that the embodiments within the scope of this disclosure can be applied to geotechnical engineering anchoring systems or methods such as tunnel support, slope reinforcement, hydraulic dam foundations, and underground caverns that have similar structures and / or functions.

[0093] In the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, the technical terms such as "installation", "connection", "joining", and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can also refer to a mechanical connection. For those skilled in the art, the specific meaning of the above terms in the embodiments of this disclosure can be understood according to the specific circumstances.

[0094] This disclosure uses specific terms to describe embodiments of the present disclosure. Terms such as "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the present disclosure. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Furthermore, certain features, structures, or characteristics in one or more embodiments of the present disclosure can be appropriately combined.

[0095] While this disclosure has described above with reference to preferred embodiments, it is not intended to limit the scope of this disclosure. Any changes and modifications can be made by those skilled in the art without departing from the spirit and scope of this disclosure. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this disclosure, without departing from the content of the technical solution, fall within the protection scope defined by the claims of this disclosure.

Claims

1. A nuclear power plant foundation pit anchoring device, characterized in that, include: Anchor bolt, sleeve and reset assembly, wherein the anchor bolt is inserted into an anchor hole opened in the rock wall, and the sleeve is fitted on the outside of the anchor bolt and fixedly installed on the rock wall; The reset assembly is provided with at least one reset unit along the axial direction of the anchor rod. The reset unit includes a first mounting rod, a second mounting rod, a first elastic element, and a second elastic element. The first mounting rod, the second mounting rod, the first elastic element, and the second elastic element are installed in the sleeve and sleeved on the outside of the anchor rod. The first elastic element is elastically connected to the first mounting rod and the second mounting rod at its two axial ends, respectively. The second elastic element is sleeved on the outside of the first mounting rod, the first elastic element and the second mounting rod. The first elastic element and the second elastic element are coaxially arranged. The first mounting rod has an inner groove, and the anchor rod has a mounting block embedded in the mounting groove.

2. The nuclear power plant foundation pit anchoring device according to claim 1, characterized in that, The first elastic element is a disc spring, which includes multiple coaxially stacked disc springs.

3. The nuclear power plant foundation pit anchoring device according to claim 1, characterized in that, The second elastic element is a helical compression spring.

4. The nuclear power plant foundation pit anchoring device according to claim 1, characterized in that, The first mounting rod has a first baffle on the side opposite to the second mounting rod, and the second mounting rod has a second baffle on the side opposite to the first mounting rod. The two ends of the second elastic element elastically abut against the first baffle and the second baffle, respectively.

5. The nuclear power plant foundation pit anchoring device according to claim 1, characterized in that, The reset assembly has at least two reset units arranged along the axial direction of the anchor rod, and a fixing seat is provided between adjacent reset units. The fixing seat is sleeved on the outside of the anchor rod and positioned at the target position of the anchor rod. The fixed seat is annular, and its outer peripheral wall is provided with multiple balls, which roll and abut against the inner wall of the sleeve.

6. The nuclear power plant foundation pit anchoring device according to claim 1, characterized in that, The sleeve is provided with a connecting flange on the outside. One end of the reset assembly extends to the bottom of the sleeve, and the other end is provided with a stop plate. The second elastic element of the reset unit near the outside of the anchor hole abuts against the stop plate. The anchoring device also includes a support component, which includes a housing with a mating flange. The housing is anchored to the rock wall by a plurality of threaded connectors that pass through the mating flange, the stop plate and the connecting flange in sequence to be fixedly connected to the rock wall.

7. The nuclear power plant foundation pit anchoring device according to claim 6, characterized in that, The connecting flange is also provided with an extension cylinder on the side opposite to the reset unit. The support also includes a mounting bracket and a connector, both of which are located inside the housing. The mounting bracket is fitted onto the outside of the extension tube and fixedly connected to the outer shell, and the connector is threadedly connected to the mounting bracket.

8. The nuclear power plant foundation pit anchoring device according to claim 7, characterized in that, The mounting bracket has an elastic ring on the side opposite to the reset assembly, and the inner wall of the elastic ring presses against the outer wall of the extension cylinder.

9. The nuclear power plant foundation pit anchoring device according to claim 8, characterized in that, The elastic ring is fixed to the mounting bracket and sleeved on the outside of the extension cylinder, and the elastic ring includes a plurality of spaced-apart snap-fit ​​blocks, which elastically retract inward toward the axial direction of the extension cylinder.

10. The nuclear power plant foundation pit anchoring device according to claim 9, characterized in that, The connector has an internal bevel. When the connector is screwed into the mounting bracket, the bevel presses against the snap-fit ​​block, so that the elastic ring elastically presses against the outer wall of the extension cylinder.

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