Prestressed anti-floating anchor rod
By designing a prestressed anti-buoyancy anchor structure, the installation of the anchor and the grouting process can be carried out simultaneously, which solves the problems of low construction efficiency and inaccurate positioning, and improves the stability and pull-out bearing capacity of the anchor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHAANXI HUASHAN CONSTR
- Filing Date
- 2025-07-18
- Publication Date
- 2026-07-07
AI Technical Summary
Existing anti-buoyancy anchor construction technology suffers from low efficiency in process connection and lack of positioning devices, resulting in long construction period, reduced anchoring force and uneven stress.
The prestressed anti-buoyancy anchor structure, including anchor head, anchor pipe, threaded rod and anchor plate, is adopted. Through the anchor positioning structure and multi-point anchoring design, combined with the integration of the grouting system, the anchor installation and grouting process can be carried out simultaneously. The positioning steel plate and spring-steel plate composite buffer system ensure the verticality and controllability of prestress application.
It improves construction efficiency, ensures the stability and long-term performance of anchor bolts, solves the problems of low process connection efficiency and lack of positioning devices in traditional processes, and enhances pull-out bearing capacity and anti-buoyancy effect.
Smart Images
Figure CN224468367U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of building construction technology, and in particular to a prestressed anti-buoyancy anchor. Background Technology
[0002] As a core component of the anti-buoyancy system for underground structures, anti-buoyancy anchors differ fundamentally from foundation piles in their technical characteristics. Foundation piles, as typical compressive strength components, primarily transfer the load from the superstructure vertically to the deep bearing layer through the pile body. Their stress mode is top-down pressure transmission, and the load magnitude dynamically changes with the building's function. Anti-buoyancy anchors, on the other hand, belong to the tensile strength system. Their main function is to resist the upward pull of groundwater buoyancy on the structure. Their stress mechanism exhibits a reverse transmission characteristic from the pile top to the pile bottom—the tensile force is dispersed to stable strata through the bond or mechanical interlocking between the anchor body and the surrounding soil and rock. This mechanical characteristic requires that the design of anti-buoyancy anchors focus on the tensile strength of the anchor body, the length of the anchoring section, and the bonding performance between the grout and the soil-rock interface. Their arrangement density and anchoring force need to be accurately verified based on the groundwater level fluctuation range, structural self-weight, and buoyancy calculations. Especially in water-rich strata or high-water areas, the anchor's tensile strength must meet the structural safety reserve requirements under extreme hydrological conditions.
[0003] The limitations of traditional anti-buoyancy anchor bolt construction techniques are becoming increasingly apparent. Current techniques employ a step-by-step approach: first, drilling to the designed depth; then, lowering the pre-tied reinforcing cage; and finally, inserting the grouting pipe for pressure grouting. However, this technique still suffers from the following technical bottlenecks: First, the process is inefficient, requiring secondary positioning of the grouting pipe after the reinforcing cage is lowered. Furthermore, the flow of grout during grouting can easily cause rebar displacement, resulting in a long construction cycle for a single anchor bolt and significantly hindering project progress. Second, the lack of positioning devices makes it easy for the reinforcing cage to tilt during lowering due to uneven soil layers or operational errors, potentially reducing the effective length of the anchoring section, decreasing anchoring force, and even causing uneven stress distribution across the entire anchor bolt group.
[0004] Therefore, this utility model proposes a prestressed anti-buoyancy anchor rod to solve the above-mentioned problems existing in the existing monitoring equipment. Utility Model Content
[0005] In view of this, the main purpose of this utility model is to provide a prestressed anti-buoyancy anchor rod to solve the problems of low process connection efficiency and lack of positioning device in existing anti-buoyancy anchor rods.
[0006] To achieve the above objectives, the basic concept of the technical solution adopted by this utility model is as follows:
[0007] A prestressed anti-buoyancy anchor bolt, comprising:
[0008] The anchor head has a conical structure and several grouting ports.
[0009] Anchor pipe is a hollow steel pipe set at the center of the anchor head. The pipe cavity forms a pressure grouting channel that is connected to the grouting port, and the other end is connected to the anchor plate.
[0010] The threaded rods are symmetrically distributed radially around the anchor pipe, and both ends of the threaded rods are rigidly connected to the anchor head and the anchor plate, respectively.
[0011] Anchor plate, set outside the anchor hole, is connected to both the anchor pipe and the threaded rod;
[0012] Anchoring positioning structure, installed on anchor pipe and threaded rod.
[0013] In a preferred embodiment, a first threaded hole is provided on the upper end face of the anchor head. The first threaded hole is threadedly connected to the anchor pipe and is also connected to the grouting port to form a continuous grout delivery channel.
[0014] In a preferred embodiment, a plurality of second threaded holes are evenly distributed circumferentially on the upper end face of the anchor head, and the second threaded holes are threadedly connected to the threaded rod.
[0015] In a preferred embodiment, the anchor plate is further provided with through holes and a plurality of prestressed holes, the through holes being matched with the anchor pipe and the prestressed holes being matched with the threaded rod.
[0016] In a preferred embodiment, the prestressed hole is a tapered channel structure with a gradually tapering inner wall that matches the locking sleeve. The locking sleeve has an elastic relief groove along the axial direction to form a radially retractable clamping structure.
[0017] In a preferred embodiment, the tail end of the anchor pipe is further threaded with a first prestressed nut, which fits against the anchor plate.
[0018] In a preferred embodiment, the tail end of the threaded rod is further threadedly connected to a second prestressed nut, which fits against the upper end of the locking sleeve.
[0019] In a preferred embodiment, the anchoring positioning structure includes:
[0020] The positioning steel plate is movably sleeved on the outside of the anchor pipe and matches the first positioning nut on the anchor pipe that is threadedly connected to the upper side of the positioning steel plate.
[0021] The prestressed steel plate is movably sleeved on the threaded rod, located below the positioning steel plate in the same group, and matches the second positioning nut that is threadedly connected to the threaded rod below the prestressed steel plate.
[0022] The spring is movably sleeved on the threaded rod and located between the positioning steel plate and the prestressed steel plate.
[0023] In a preferred embodiment, the outer edge of the positioning steel plate matches the inner wall of the anchor hole.
[0024] In a preferred embodiment, the positioning steel plate is further provided with a plurality of grout penetration holes, and the grout penetration holes on different groups of positioning steel plates are staggered.
[0025] Compared with the prior art, this utility model provides a prestressed anti-buoyancy anchor rod, which has the following beneficial effects:
[0026] 1. This prestressed anti-buoyancy anchor rod forms a grouting system through the setting of anchor pipe and anchor head, which makes it easy to combine the installation of grouting pipe and anchor rod into one step during use, effectively reducing the number of procedures and improving construction efficiency.
[0027] 2. The use of multiple threaded rods facilitates multi-point anchoring during prestressing and enables multi-position grouting fixation, ensuring the stability of the anchor structure after grouting.
[0028] 3. By setting up an anchoring and positioning structure, with a positioning steel plate as the core guiding component, and through the dynamic fit between the outer edge of the positioning steel plate and the inner wall of the anchor hole, the relative perpendicularity of the anchor rod to the anchor hole during installation is effectively guaranteed. Simultaneously, through a mechanical-elastic synergistic mechanism, the controllability of prestress application is ensured, and stress loss caused by ground creep is effectively compensated, significantly improving the long-term working performance of the anchor rod. This solves the problems of low process connection efficiency and lack of positioning devices in existing anti-buoyancy anchor rods.
[0029] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings. Attached Figure Description
[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0031] Figure 1 This is a schematic diagram of the prestressed anti-buoyancy anchor rod of this utility model;
[0032] Figure 2 This is a schematic diagram of the structure of the anchor head of this utility model;
[0033] Figure 3 This is a cross-sectional view of the anchor head of this utility model;
[0034] Figure 4 This is a schematic diagram of the anchor fixing structure of this utility model;
[0035] Figure 5 This is a front view of the anchoring and positioning structure of this utility model;
[0036] Figure 6 This is a schematic diagram of the structure of the anchor plate of this utility model;
[0037] Figure 7 This is a cross-sectional view of the anchor plate of this utility model;
[0038] Figure 8 This is a schematic diagram of the structure of the second prestressed nut and locking sleeve of this utility model.
[0039] [Explanation of Key Component Symbols]
[0040] 1. Anchor head; 2. Anchor pipe; 3. Threaded rod; 4. Positioning steel plate; 5. Prestressed steel plate; 6. Spring; 7. Anchor plate; 8. First positioning nut; 9. Tightening nut; 10. First threaded hole; 11. Grouting port; 12. Second threaded hole; 13. Grouting hole; 14. Second positioning nut; 15. First prestressed nut; 16. Second prestressed nut; 17. End cap; 18. Prestressed hole; 19. Locking sleeve. Detailed Implementation
[0041] The structure of this prestressed anti-buoyancy anchor will be further described in detail below with reference to the accompanying drawings and embodiments of this utility model.
[0042] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0043] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments as described in this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0044] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0045] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.
[0046] The following is combined Figures 1 to 8 This invention describes the prestressed anti-buoyancy anchor rod.
[0047] A prestressed anti-buoyancy anchor bolt, the anchor bolt structure is an assembled anchor bolt, including an anchor head 1, an anchor pipe 2, a threaded rod 3 and an anchor plate 7. The anchor head 1 is a conical structure, installed at the lower end of the anchor pipe 2 and threaded rod 3, and is detachably connected to both the anchor pipe 2 and threaded rod 3. Several grouting ports 11 are provided on the anchor head 1. The anchor pipe 2 is a hollow steel pipe detachably installed at the center of the anchor head 1. The pipe cavity forms a pressure grouting channel communicating with the grouting ports 11, and the other end is detachably connected to the anchor plate 7. Multiple threaded rods 3 are symmetrically distributed radially around the anchor pipe 2, and each threaded rod 3 has a standard threaded interface at both ends, which can form a rigid connection with the anchor head 1 and the anchor plate 7 respectively. Several sets of anchor fixing structures are also provided on the anchor pipe 2 and threaded rod 3 to facilitate positioning of the anchor rod structure within the anchor hole, preventing the anchor rod from shifting during installation. The anchor plate 7 is installed on the outside of the anchor hole and is used to seal the opening of the anchor hole when prestressing is applied to the threaded rod 3, preventing grout leakage.
[0048] In the above description, the tapered structure of the anchor head 1 facilitates its role as the load-bearing core of the prestressed anti-buoyancy anchor, allowing it to be easily lowered into the anchor hole under gravity, preventing tilting during the process. The anchor pipe 2 and anchor head 1 form a grouting system, allowing the installation of the grouting pipe and the anchor to be combined into a single step, effectively reducing procedures. Multiple threaded rods 3 facilitate multi-point anchoring during prestressing application and simultaneous multi-position grouting fixation. The anchor plate 7 integrates the dual functions of prestressing application and grouting. During tensioning, the anchor plate 7 acts as a reaction base, bearing the force of the jack, and transmits the prestress to the anchoring section through the threaded rods 3. Simultaneously, pressure grouting is performed through the cavity of the anchor pipe 2. Grout overflows from the grouting port 11 at the end of the anchor head 1 and returns along the gaps in the threaded rods 3, forming a full-section encapsulated anchor body.
[0049] In a preferred embodiment, such as Figure 1 , Figure 2 and Figure 3 As shown, a first threaded hole 10 is provided on the upper end face of the anchor head 1. The first threaded hole 10 is threadedly connected to the external thread of the anchor pipe 2, and the first threaded hole 10 is also connected to the grouting port 11 to form a continuous grout conveying channel.
[0050] In the above description, the coaxial nesting design allows the anchor pipe 2 to function as both a structural load-bearing component and a grouting pipeline, integrating the anchor bolt installation and grouting system layout processes. This significantly simplifies the complex process of anchor bolt installation and secondary lowering of the grouting pipe in traditional methods. During grouting, the grout is transported through the inner cavity of the anchor pipe 2 to the end of the anchor head 1, and then permeates into the bottom of the hole through the pre-set grouting port 11, creating a gradual filling effect from bottom to top.
[0051] In a preferred embodiment, such as Figure 1 , Figure 2 and Figure 3 As shown, the upper surface of the anchor head 1 has a plurality of second threaded holes 12 evenly distributed circumferentially. These second threaded holes 12 form a multi-directional connection node, and each hole is precisely connected to the end of the threaded rod 3 via a standard thread. To enhance the axial stability of the rod, a tightening nut 9 is also threadedly connected to the lower end of the threaded rod 3. This tightening nut 9 eliminates connection gaps through mechanical locking, ensuring that the multiple threaded rods 3 form a stable spatial force-bearing system.
[0052] In the above description, the above settings are used in the following ways: First, the multi-point anchoring mechanism can effectively disperse the prestressed load and improve the pull-out bearing capacity of the anchor rod; second, the gap of the threaded rod 3 forms a natural grout return channel, which can help to achieve full-section grouting; third, the modular connection method facilitates later maintenance and stress retesting.
[0053] In a preferred embodiment, such as Figure 1 , Figure 6 , Figure 7 and Figure 8 As shown, the anchor plate 7 is also provided with through holes and several prestressed holes 18. The through holes are used in conjunction with the anchor pipe 2 to facilitate the protrusion of the tail end of the anchor pipe 2, and also serve to fix the anchor pipe 2. The prestressed holes 18 are used in conjunction with the threaded rod 3 to facilitate the threading of the threaded rod 3 during use.
[0054] Specifically, such as Figure 1 , Figure 6 and Figure 7 As shown, a first prestressed nut 15 is threadedly connected to the tail end of the anchor pipe 2. The first prestressed nut 15 is used in conjunction with the anchor plate 7 to abut against the anchor plate 7 during installation and fix the tail end of the anchor pipe 2. An end cap 17 is also provided at the tail end of the anchor pipe 2 to protect the internal cavity of the anchor pipe 2 before grouting.
[0055] Specifically, such as Figure 1 , Figure 6 , Figure 7 and Figure 8 As shown, the prestressed hole 18 adopts a tapered channel structure with a gradually tapered inner wall design, which forms a mechanical fit with the special prestressed locking sleeve 19. The outer wall tapering of the locking sleeve 19 is completely matched with the inner wall of the prestressed hole 18. An elastic relief groove is opened along the axial direction of the sleeve to form a radially retractable clamping structure.
[0056] In the above description, during the prestressing application process, the operator inserts the prestressing locking sleeve 19 axially into the tapered hole, and uses a special tool to pass the threaded rod 3 through the inner cavity of the locking sleeve 19; then, the second prestressing nut 16 is tightened, and the axial feed of the threaded pair forces the locking sleeve 19 to undergo radial expansion deformation. As the outer wall of the locking sleeve 19 gradually fits against the inner wall of the tapered prestressing hole 18, multiple annular ridges form an interference fit with the hole wall, ultimately generating a continuous preload force in the axial direction of the threaded rod 3. This wedge-shaped self-locking structure not only ensures the axial positioning accuracy of the threaded rod 3, but also effectively resists the relaxation of the rod under external loads through frictional damping effect, significantly improving the long-term stability of the prestressed anchoring system.
[0057] In a preferred embodiment, such as Figure 1 , Figure 4 and Figure 5As shown, the anchoring positioning structure includes a positioning steel plate 4, a prestressed steel plate 5, and a spring 6. The positioning steel plate 4 is movably sleeved on the outside of the anchor pipe 2 and is fixed and adjusted by a first positioning nut 8 threadedly connected to the anchor pipe 2 on the upper side of the positioning steel plate 4. The outer edge of the positioning steel plate 4 is used in conjunction with the anchor hole to position the anchor structure during anchor installation. The prestressed steel plate 5 is movably sleeved on the threaded rod 3, located below the positioning steel plates 4 in the same group, and is fixed and adjusted by a second positioning nut 14 threadedly connected to the threaded rod 3 on the lower side of the prestressed steel plate 5. The spring 6 is movably sleeved on the threaded rod 3 and located between the positioning steel plate 4 and the prestressed steel plate 5.
[0058] In the above description, this anchoring positioning structure adopts a three-stage adjustment mechanism to achieve precise centering. In specific use, the positioning steel plate 4 serves as the core guiding component, and is installed on the outside of the anchor pipe 2 through a movable sleeve, with its outer edge forming a dynamic fit with the inner wall of the anchor hole. During use, the operator can drive the positioning steel plate 4 to move axially along the anchor pipe 2 by rotating the first positioning nut 8 on the anchor pipe 2, thereby precisely adjusting the radial position of the anchor rod. During use, the number and diameter of the positioning steel plates 4 can be increased or decreased according to the geological conditions to adapt to the construction needs of different hole diameters.
[0059] The aforementioned anchoring and positioning structure employs a spring-steel plate composite buffer structure. The prestressed steel plate 5 is fixed to the threaded rod 3 via threaded connectors, forming an adjustable-space rigid frame with the positioning steel plate 4. The spring 6, fitted between the positioning steel plate 4 and the prestressed steel plate 5, constitutes an elastic buffer layer. During the prestressing tensioning stage, tightening the second positioning nut 14 causes axial displacement of the prestressed steel plate 5, compressing the spring 6 to accumulate elastic potential energy. In use, this structure achieves a dual function: in the initial tensioning stage, the compression deformation of the spring 6 absorbs stress fluctuations in the rod, forming a gradual pre-tensioning process; in the later tensioning stage, the reaction force of the spring 6 couples with the axial force of the threaded rod 3, transforming into continuous anchoring pressure through the prestressing locking sleeve 19. This mechanical-elastic synergistic mechanism ensures the controllability of prestress application and effectively compensates for stress losses caused by ground creep, significantly improving the long-term performance of the anchor bolt.
[0060] Specifically, such as Figure 1 and Figure 4 As shown, several grout-permeable holes 13 are also provided on the positioning steel plate 4, and the grout-permeable holes 13 on different sets of positioning steel plates 4 are staggered. This facilitates the passage of grout through the grout-permeable holes 13 during use, allowing the grout to fill the anchor hole. The staggered arrangement of the grout-permeable holes 13 also improves the density of the grout in the anchor hole during grouting.
[0061] The usage process and operating principle of the prestressed anti-buoyancy anchor rod described in this utility model include:
[0062] First, the anchor head 1, anchor pipe 2, and threaded rod 3 are installed to form the main structure of the anti-buoyancy anchor. Then, the anchor positioning structure is selected according to the depth and diameter of the corresponding anchor hole. During the process of lowering the prestressed anti-buoyancy anchor after installation, the verticality error of the anchor in the anchor hole is controlled by the dynamic adaptation mechanism between the positioning steel plate 4 and the anchor hole wall, combined with the axial adjustment function of the spring-steel plate composite buffer system, to avoid the anchor shifting during installation. After the anchor is installed, grout is injected into the anchor hole through the anchor pipe 2 to achieve controllable filling of grout from the end of the anchor head to the hole opening. Finally, the anchor plate 7 is installed, and prestress is applied to the threaded rod 3 to form a composite anchor body with high bonding strength.
[0063] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model.
Claims
1. A prestressed anti-buoyancy anchor bolt, characterized in that, include: The anchor head (1) has a conical structure and several grouting ports (11) are provided on the anchor head (1); Anchor pipe (2) is a hollow steel pipe set at the center of anchor head (1). The pipe cavity forms a pressure grouting channel that is connected to the grouting port (11), and the other end is connected to the anchor plate (7). The threaded rod (3) is symmetrically distributed radially around the anchor pipe (2), and is rigidly connected to the anchor head (1) and the anchor plate (7) at both ends of the threaded rod (3); Anchor plate (7) is set outside the anchor hole and is connected to both anchor pipe (2) and threaded rod (3); An anchoring structure is installed on the anchor pipe (2) and the threaded rod (3).
2. The prestressed anti-buoyancy anchor bolt as described in claim 1, characterized in that, The upper end face of the anchor head (1) is provided with a first screw hole (10), which is threadedly connected to the anchor pipe (2) and is also connected to the grouting port (11) to form a continuous grout conveying channel.
3. A prestressed anti-buoyancy anchor bolt as described in claim 1, characterized in that, The upper surface of the anchor head (1) has several second screw holes (12) evenly distributed in a circumferential direction, and the second screw holes (12) are threadedly connected to the threaded rod (3).
4. A prestressed anti-buoyancy anchor bolt as described in claim 1, characterized in that, The anchor plate (7) is also provided with through holes and several prestressed holes (18). The through holes are matched with the anchor pipe (2), and the prestressed holes (18) are matched with the threaded rod (3).
5. A prestressed anti-buoyancy anchor bolt as described in claim 4, characterized in that, The prestressed hole (18) is a tapered channel structure with a tapered inner wall that matches the locking sleeve (19). The locking sleeve (19) has an elastic relief groove along the axial direction to form a radially retractable clamping structure.
6. A prestressed anti-buoyancy anchor bolt as described in claim 5, characterized in that, The tail end of the anchor pipe (2) is also threaded with a first prestressed nut (15), which is in contact with the anchor plate (7).
7. A prestressed anti-buoyancy anchor bolt as described in claim 5, characterized in that, The tail end of the threaded rod (3) is also threadedly connected to a second prestressed nut (16), which is in contact with the upper end of the locking sleeve (19).
8. A prestressed anti-buoyancy anchor bolt as described in claim 1, characterized in that, The anchoring and positioning structure includes: The positioning steel plate (4) is movably sleeved on the outside of the anchor pipe (2) and matches the first positioning nut (8) threaded on the anchor pipe (2) on the upper side of the positioning steel plate (4); The prestressed steel plate (5) is movably sleeved on the threaded rod (3), located on the lower side of the positioning steel plate (4) in the same group, and matched with the second positioning nut (14) threaded on the threaded rod (3) on the lower side of the prestressed steel plate (5); The spring (6) is movably sleeved on the threaded rod (3) and located between the positioning steel plate (4) and the prestressed steel plate (5).
9. A prestressed anti-buoyancy anchor bolt as described in claim 8, characterized in that, The outer edge of the positioning steel plate (4) matches the inner wall of the anchor hole.
10. A prestressed anti-buoyancy anchor bolt as described in claim 8, characterized in that, The positioning steel plate (4) is also provided with a number of grout passage holes (13), and the grout passage holes (13) on different groups of positioning steel plates (4) are staggered.