Self-locking prestressed anchorage device based on tension self-adaptation

Abstract

The utility model provides a kind of self-locking prestressed anchorage device based on tension self-adaption, reduce sudden anchoring failure by mechanical and geometric dual locking mechanism, reduce prestressed compensation tension frequency reduce maintenance cost, it includes: self-locking tension end anchorage device, top is provided with eccentric arrangement's slurry outlet;Embedded pipe, top is inserted to the bottom of self-locking tension end anchorage device;Self-locking fixed end anchorage device, the bottom of embedded pipe is inserted to the top of self-locking fixed end anchorage device, and the body of self-locking fixed end anchorage device is provided with slurry inlet pipe;Self-locking extruded cable body, top is connected the bottom of self-locking fixed end anchorage device, and bottom cable body is provided with slurry inlet pipe;Wherein, self-locking tension end anchorage device and self-locking fixed end anchorage device are built-in self-locking structure, and the self-locking structure includes clamping piece assembly and the tapered locking cavity matched with clamping piece assembly.

Description

Technical Field

[0001] This utility model relates to the field of prestressed anchors, and more specifically, to a self-locking prestressed anchor based on tension self-adaptation. Background Technology

[0002] As a core load-bearing component in modern bridges, buildings, and geotechnical engineering, the reliability of prestressed anchorage systems directly determines the structural lifespan and safety. Traditional wedge-type anchorages are prone to the following problems in long-term use: 1. Existing wedge structures rely on friction anchoring, which is prone to stress relaxation of 3%-5% under dynamic loads and temperature differences, leading to beam deflection and crack propagation; the wedge retraction amount reaches 6-8mm, requiring repeated compensation tensioning, which increases construction costs; 2. Conventional centrally symmetrical grouting holes are prone to cavitation and accumulation, which creates corrosion channels after the grout hardens, leading to frequent steel strand corrosion and breakage accidents; the fixed-end single-point grouting mode causes grout segregation and stratification, resulting in insufficient strength in the core area; 3. Traditional wedges experience brittle slippage during over-tensioning, and the conical cavity of the anchor block lacks a progressive locking mechanism, which may lead to anchor breakage accidents. Stress concentration cracks in the wedge assembly are concentrated at the top of the conical surface, resulting in a fatigue life of less than 500,000 cycles. Utility Model Content

[0003] The purpose of this invention is to provide a tension-adaptive self-locking prestressed anchor that reduces sudden anchorage failure, reduces the number of prestress compensation tensioning cycles, and reduces maintenance costs through a dual mechanical and geometric locking mechanism.

[0004] The embodiments of this utility model are implemented as follows: A tension-adaptive self-locking prestressed anchorage, comprising: The self-locking tensioning end anchor has an eccentrically arranged slurry outlet at the top; The pre-embedded pipe is inserted at the top to the bottom of the self-locking tensioning end anchor. The self-locking fixed-end anchor has a pre-embedded pipe inserted from the bottom to the top of the self-locking fixed-end anchor, and the anchor body of the self-locking fixed-end anchor is equipped with a grout inlet pipe. The self-locking extrusion cable body is connected to the bottom of the self-locking fixed end anchor at the top, and the bottom cable body is equipped with a grout inlet pipe; The self-locking tensioning end anchor and the self-locking fixed end anchor have a built-in self-locking structure, which includes a clamping plate assembly and a conical locking cavity that cooperates with the clamping plate assembly.

[0005] In a preferred embodiment of this utility model, the self-locking tensioning end anchor is a 17-hole circular anchor, which includes: The circular anchor block has three layers of steel strand holes in the center. The center layer has one hole, the second layer has six holes arranged in a ring around the center, and the third layer has ten holes arranged in a ring. The anchor pad has a frustum cylindrical structure, with its large-diameter end fixed below the circular anchor block and having a diameter larger than that of the circular anchor block; the outer extension area of ​​the anchor pad is provided with a ring array of mounting holes and an eccentrically arranged grout outlet.

[0006] In a preferred embodiment of the present invention, the clamping plate assembly includes three separate clamping plates. The inner wall of the clamping plate is provided with serrated patterns that engage with the steel strand, and the outer wall is a conical surface that matches the conical locking cavity. The inner wall of the conical locking cavity is provided with an circumferential locking groove, and the outer wall of the clamping plate is provided with an elastic locking protrusion. The two constitute a tension adaptive locking structure.

[0007] In a preferred embodiment of the present invention, the above-mentioned circumferential locking groove is a double spiral locking groove group, including two staggered spiral locking grooves. The cross-section of each spiral locking groove is trapezoidal tooth-shaped, the tooth tip angle is 90-110°, and the groove depth to the height of the clamping plate cone surface is 1:8-1:10.

[0008] In a preferred embodiment of this utility model, the aforementioned elastic locking protrusion is a spring steel ball assembly embedded in the outer wall of the clamping plate. When it moves down along the conical locking cavity under tension, the spring steel ball assembly is embedded in the circumferential locking groove to achieve one-way locking.

[0009] In a preferred embodiment of this utility model, the above-mentioned spring steel ball assembly includes: The hemispherical steel ball has a spiral locking groove with a bottom width to diameter ratio of 1:1.2-1.5. Disc springs, pre-compressed and mounted at the bottom of the steel balls; The sealing steel sleeve has drainage micro-holes on its side wall with a diameter ≤0.5mm.

[0010] In a preferred embodiment of this utility model, in the above-mentioned double-helix locking groove assembly: The helical lead angle of the two helical locking grooves is 30-45°; A stress diffusion concave arc is provided between adjacent slot teeth, and the ratio of the concave arc radius to the steel ball diameter is 0.3-0.5:1; The spring ball locking unit is evenly distributed in three groups at 120° circumference, and the top of the ball protrudes from the outer surface of the clip by 0.25-0.3 times the diameter of the ball.

[0011] In a preferred embodiment of the present invention, a limiting boss is provided at the bottom of the conical surface of the above-mentioned clamping plate assembly, and the height of the boss is 1.5-2 times the height of the top of the steel ball protruding from the outer surface of the clamping plate; The tapered locking cavity entrance is equipped with a matching stepped locking shoulder. When the clamping plate is fully locked, the limiting boss and the locking shoulder form an axial abutment.

[0012] In a preferred embodiment of the present invention, the grouting hole of the anchor pad is connected to the inner cavity of the pre-embedded pipe through an inclined channel, and the central axis of the grouting hole forms an angle of 5-15° with the central axis of the pre-embedded pipe.

[0013] In a preferred embodiment of the present invention, the self-locking extrusion cable body includes a high-strength steel wire bundle and an extruded anchor sleeve. The inner wall of the anchor sleeve is provided with spiral embossing that engages with the steel wire bundle, and the outer wall is provided with locking threads that are threadedly connected to the second self-locking fixed end anchor.

[0014] The beneficial effects of this utility model embodiment are as follows: By setting a new clamping plate assembly and a conical locking cavity at the tensioning end and the fixing end, the elastic locking protrusion on the outer wall of the clamping plate cooperates with the double helical locking groove of the conical cavity to achieve progressive unidirectional locking driven by tension force. After the steel ball is embedded in the trapezoidal tooth groove, a mechanical interlock is formed, which effectively resists the retraction of the steel strand. At the same time, the staggered double helical grooves evenly distribute the locking force to the conical cavity wall, reduce local stress concentration, and improve long-term anchoring stability. Compared with traditional clamping plate anchors, the prestress loss can be reduced by 15%-25%. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a structural schematic diagram of a tension-adaptive self-locking prestressed anchorage according to an embodiment of the present invention. Figure 2 This is a top view of the self-locking tensioning end anchorage according to an embodiment of the present utility model; Figure 3 This is a schematic diagram of the clip assembly structure according to an embodiment of the present utility model; Figure 4 A schematic diagram of the conical locking cavity structure for the clamping plate assembly at the position of the steel strand hole in this embodiment of the present invention; Figure 5 This is a schematic diagram of the circumferential locking groove structure according to an embodiment of the present utility model.

[0017] Icons: 1. Self-locking tensioning end anchor; 11. Grout outlet; 12. Circular anchor block; 13. Anchor pad; 14. Steel strand hole; 2. Embedded pipe; 3. Self-locking fixed end anchor; 4. Self-locking extrusion cable body; 5. Self-locking structure; 51. Clamping plate assembly; 511. Serrated pattern; 512. Elastic locking protrusion; 5121. Hemispherical steel ball; 5122. Disc spring; 5123. Sealing steel sleeve; 513. Limiting boss; 514. Locking shoulder; 52. Conical locking cavity; 521. Circumferential locking groove; 5211. Spiral locking groove; 5212. Stress diffusion concave arc; 6. Grout inlet pipe. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are used only for the convenience of describing this utility model and for simplifying the description, and do not 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 utility model. Furthermore, the terms "", "", "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0022] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0023] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] Example Please refer to Figure 1-5 This embodiment provides a tension-adaptive self-locking prestressed anchor, which includes a self-locking tensioning end anchor 1, a pre-embedded pipe 2, a self-locking fixed end anchor 3, and a self-locking compression cable body 4 connected in sequence.

[0025] The top of the self-locking tensioning end anchor 1 is provided with an eccentrically arranged grout outlet 11 to guide air bubbles to rise and be discharged naturally. The top of the pre-embedded pipe 2 is inserted into the bottom of the self-locking tensioning end anchor 1; the bottom of the pre-embedded pipe 2 is inserted into the top of the self-locking fixed end anchor 3. The anchor body of the self-locking fixed end anchor 3 is provided with a grout inlet pipe 6; the top of the pre-embedded pipe 2 is connected to the bottom of the self-locking fixed end anchor 3, and the bottom cable body is provided with a grout inlet pipe 6. The fixed end and the cable body adopt a double grout inlet pipe 6 design to achieve bidirectional pressure grouting. Among them, the self-locking tensioning end anchor 1 and the self-locking fixed end anchor 3 have a built-in self-locking structure 5, which includes a clamping assembly 51 and a conical locking cavity 52 that cooperates with the clamping assembly 51. Multiple grout inlets and eccentric grout outlets form a grouting network to achieve void-free dense filling. The tension adaptive locking mechanism converts the retraction energy of the steel strand into locking force.

[0026] In this embodiment, both the self-locking tensioning end anchor 1 and the self-locking fixed end anchor 3 are 17-hole circular anchors, which include a circular anchor block 12 and an anchor pad 13. The circular anchor block 12 has three layers of distributed steel strand holes 14 at its center. The central layer has one hole, the second layer has six holes arranged in a ring around the center, and the third layer has ten holes arranged in a ring, which optimizes the spatial arrangement of the steel strands and improves the compressive strength of the anchor block. The anchor pad 13 has a frustum cylindrical structure, with the large-diameter end fixed below the circular anchor block 12 and the diameter is larger than that of the circular anchor block 12. The outer extension area of ​​the anchor pad 13 has a ring array of mounting holes and an eccentrically arranged grout outlet 11, which increases the bearing area and resists local concrete splitting.

[0027] The self-locking fixed-end anchor has a similar structure to the self-locking tensioning-end anchor, including a circular anchor block and an anchor pad, but it does not have a grout outlet.

[0028] The clamping plate assembly 51 and the conical locking cavity 52 that cooperates with the clamping plate assembly 51 are located in the area of ​​the steel strand hole 14. Specifically, the clamping plate assembly 51 adopts three separate clamping plates for easy on-site replacement. The inner wall of the clamping plate is provided with serrated patterns 511 that engage with the steel strand, and the outer wall is a conical surface that matches the conical locking cavity 52. ​​The inner wall of the conical locking cavity 52 is provided with an circumferential locking groove 521, and the outer wall of the clamping plate is provided with an elastic locking protrusion 512. The two together form a tension adaptive locking structure.

[0029] Specifically, the circumferential locking groove 521 is a double-helix locking groove group, including two staggered helical locking grooves 5211. The cross-section of each helical locking groove 5211 is trapezoidal toothed, with a tooth apex angle of 90-110°. The groove depth to the height of the clamping plate cone surface is 1:8-1:10. The staggered double helix grooves evenly distribute the locking force to the conical cavity wall, reducing local stress concentration and improving long-term anchoring stability. The elastic locking protrusion 512 on the outer wall of the clamping plate cooperates with the double helix locking grooves 5211 in the conical cavity to achieve progressive unidirectional locking driven by tension force. After the steel ball is embedded in the trapezoidal toothed groove, it forms a mechanical interlock, effectively resisting the retraction of the steel strand.

[0030] The elastic locking protrusion 512 is a spring steel ball assembly embedded in the outer wall of the clamping plate. When it moves downward along the conical locking cavity 52 under tension, the spring steel ball assembly is embedded in the circumferential locking groove 521 to achieve one-way locking. Specifically, the spring steel ball assembly includes a hemispherical steel ball 5121, a disc spring 5122, and a sealing steel sleeve 5123. The ratio of the width of the bottom of the spiral locking groove 5211 to the diameter of the hemispherical steel ball 5121 is 1:1.2-1.5. The pre-compression force of the disc spring 5122 of the spring steel ball ensures that the steel ball and the groove are tightly fitted. The disc spring 5122 is pre-compressed and installed at the bottom of the steel ball. The pre-compression force of the disc spring 5122 of the spring steel ball ensures that the steel ball and the groove are tightly fitted. The side wall of the sealing steel sleeve 5123 has drainage micro-holes with a diameter ≤0.5mm.

[0031] In the double-helix locking groove group 5211 of this embodiment: the helix lead angle of the two helix locking grooves 5211 is 30-45°; a stress diffusion concave arc 5212 is provided between adjacent groove teeth, and the ratio of the concave arc radius to the steel ball diameter is 0.3-0.5:1. The stress diffusion concave arc 5212 between the locking groove teeth, with a concave arc radius: steel ball diameter = 0.3-0.5:1, alleviates the propagation of microcracks under cyclic loading.

[0032] The spring ball locking unit is evenly distributed in three groups at 120° circumference. The top of the ball protrudes from the outer surface of the clamping plate by 0.25-0.3 times the diameter of the ball. The three groups of 120° distributed ball components lock synchronously to avoid off-center load failure.

[0033] The clamping plate assembly 51 has a limiting boss 513 at the bottom of its conical surface, with a boss height of 1.5-2 times the height of the top of the steel ball protruding from the outer surface of the clamping plate. A matching stepped locking shoulder 514 is provided at the entrance of the conical locking cavity 52. ​​When the clamping plate is fully locked, the limiting boss 513 and the locking shoulder 514 form an axial abutment. The limiting boss 513 at the bottom of the clamping plate's conical surface forms a rigid abutment with the stepped shoulder at the entrance of the conical cavity, with a boss height equal to 1.5-2 times the height of the exposed steel ball, to prevent slippage under overload.

[0034] The grouting hole of the anchor pad 13 is connected to the inner cavity of the pre-embedded pipe 2 through an inclined channel, and the central axis of the grouting hole is at an angle of 5-15° with the central axis of the pre-embedded pipe 2. The grouting hole of the anchor pad 13 is at an inclination angle of 5-15° with the pre-embedded pipe 2, forming a spiral slurry flow path and reducing slurry segregation.

[0035] The self-locking extrusion cable body 4 includes a high-strength steel wire bundle and an extruded anchor sleeve. The inner wall of the anchor sleeve is provided with spiral embossing that engages with the steel wire bundle, and the outer wall is provided with locking threads that are threadedly connected to the second self-locking fixed end anchor 3.

[0036] The beneficial effects of this utility model embodiment are as follows: By setting a new clamping plate assembly 51 and a conical locking cavity 52 at the tensioning end and the fixing end, the elastic locking protrusion 512 on the outer wall of the clamping plate cooperates with the double helical locking groove 5211 of the conical cavity to achieve progressive unidirectional locking driven by tension force. After the steel ball is embedded in the trapezoidal tooth groove, a mechanical interlock is formed, which effectively resists the retraction of the steel strand. At the same time, the staggered double helical grooves evenly distribute the locking force to the conical cavity wall, reduce local stress concentration, and improve long-term anchoring stability. Compared with traditional clamping plate anchors, the prestress loss can be reduced by 15%-25%.

[0037] This specification describes examples of embodiments of the present invention, but does not imply that these embodiments illustrate and describe all possible forms of the present invention. It should be understood that the embodiments in the specification can be implemented in various alternative forms. The drawings are not necessarily drawn to scale; some features may be enlarged or reduced to show details of specific components. The specific structural and functional details disclosed should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art to implement the present invention in various forms. Those skilled in the art will understand that multiple features illustrated and described with reference to any of the drawings can be combined with features illustrated in one or more other drawings to form embodiments not explicitly illustrated or described. The illustrated combinations of features provide representative embodiments for typical applications. However, various combinations and variations of features consistent with the teachings of the present invention may be used as needed for specific applications or implementations.

[0038] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A tension-adaptive self-locking prestressed anchor, characterized in that, include: The self-locking tensioning end anchor has an eccentrically arranged slurry outlet at the top; The pre-embedded pipe is inserted at the top to the bottom of the self-locking tensioning end anchor. The self-locking fixed-end anchorage has its bottom inserted into the top of the pre-embedded pipe, and the anchor body of the self-locking fixed-end anchorage is provided with a grout inlet pipe. The self-locking compression cable body has its top connected to the bottom of the self-locking fixed end anchor, and the bottom cable body is equipped with a grout inlet pipe. The self-locking tensioning end anchor and the self-locking fixed end anchor have a built-in self-locking structure, which includes a clamping plate assembly and a conical locking cavity that cooperates with the clamping plate assembly.

2. The tension-adaptive self-locking prestressed anchorage according to claim 1, characterized in that, The self-locking tensioning end anchor is a 17-hole circular anchor, which includes: The circular anchor block has three layers of steel strand holes in the center. The center layer has 1 hole, the second layer has 6 holes in a ring array with the center as the center, and the third layer has 10 holes in a ring array. The anchor pad has a frustum cylindrical structure, with its large-diameter end fixed below the circular anchor block and having a diameter larger than that of the circular anchor block; the outer extension area of ​​the anchor pad is provided with a ring array of mounting holes and an eccentrically arranged slurry outlet.

3. The tension-adaptive self-locking prestressed anchorage according to claim 1, characterized in that, The clamping assembly includes three separate clamping plates. The inner wall of each clamping plate is provided with serrated patterns that engage with the steel strand, and the outer wall is a conical surface that matches the conical locking cavity. The inner wall of the conical locking cavity is provided with an circumferential locking groove, and the outer wall of the clamping plate is provided with an elastic locking protrusion. The two together form a tension adaptive locking structure.

4. The tension-adaptive self-locking prestressed anchorage according to claim 3, characterized in that, The circumferential locking groove is a double spiral locking groove group, including two staggered spiral locking grooves. The cross-section of each spiral locking groove is trapezoidal tooth-shaped with a tooth tip angle of 90-110° and the groove depth to the height of the clamping plate cone surface is 1:8-1:

10.

5. The tension-adaptive self-locking prestressed anchorage according to claim 4, characterized in that, The elastic locking protrusion is a spring steel ball assembly embedded in the outer wall of the clamping plate. When it moves down along the conical locking cavity under tension, the spring steel ball assembly is embedded in the circumferential locking groove to achieve one-way locking.

6. The tension-adaptive self-locking prestressed anchorage according to claim 5, characterized in that, The spring ball assembly includes: The hemispherical steel ball has a spiral locking groove with a bottom width to diameter ratio of 1:1.2-1.

5. Disc springs, pre-compressed and mounted at the bottom of the steel balls; The sealing steel sleeve has drainage micro-holes on its side wall with a diameter ≤0.5mm.

7. The tension-adaptive self-locking prestressed anchorage according to claim 6, characterized in that, In the double helix locking groove assembly: The helical lead angle of the two helical locking grooves is 30-45°; A stress diffusion concave arc is provided between adjacent slot teeth, and the ratio of the concave arc radius to the steel ball diameter is 0.3-0.5:1; The locking units of the spring steel balls are evenly distributed in three groups at 120° circumference, and the height of the top of the steel ball protruding from the outer surface of the clip is 0.25-0.3 times the diameter of the steel ball.

8. The tension-adaptive self-locking prestressed anchorage according to claim 7, characterized in that, The clamping plate assembly has a limiting boss at the bottom of its conical surface, and the height of the boss is 1.5-2 times the height of the top of the steel ball protruding from the outer surface of the clamping plate. The tapered locking cavity entrance is provided with a matching stepped locking shoulder. When the clamping piece is fully locked, the limiting boss and the locking shoulder form an axial abutment.

9. The tension-adaptive self-locking prestressed anchorage according to claim 2, characterized in that, The grouting hole of the anchor pad is connected to the inner cavity of the pre-embedded pipe through an inclined channel, and the central axis of the grouting hole forms an angle of 5-15° with the central axis of the pre-embedded pipe.

10. The tension-adaptive self-locking prestressed anchorage according to claim 1, characterized in that, The self-locking extrusion cable body includes a high-strength steel wire bundle and an extruded anchor sleeve. The inner wall of the anchor sleeve is provided with spiral embossing that engages with the steel wire bundle, and the outer wall is provided with locking threads that are threadedly connected to the second self-locking fixed end anchor.

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