Clamping type anchorage device suitable for CFRP stranded wire or rib material
By optimizing the design of the steel sleeve, clamps, and aluminum sleeve, the friction and adhesion are enhanced, solving the problems of excessive compressive stress and excessive volume during the anchoring of CFRP strands or reinforcing bars, thus achieving efficient and convenient anchoring.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHANGAN UNIV
- Filing Date
- 2025-05-09
- Publication Date
- 2026-05-15
AI Technical Summary
Existing CFRP stranded wire or reinforcing bar anchors are prone to causing excessive compressive stress on the material surface during the anchoring process, which affects the anchoring efficiency, and they are also bulky and inconvenient to use.
A clamping anchor consisting of a steel sleeve, bolts, clamping plates, and an aluminum sleeve was designed. By optimizing the structure and surface treatment of each component, friction and adhesion are enhanced, compressive stress on CFRP strands or reinforcing bars is reduced, and efficient anchoring is ensured.
It achieves improved anchoring efficiency without damaging CFRP strands or reinforcing materials, and the anchor body is small in size, making it easy to construct.
Smart Images
Figure CN224244243U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of novel composite material technology, and in particular to clamping anchors for anchoring single carbon fiber reinforced composite strands or reinforcing bars. Background Technology
[0002] Carbon fiber reinforced polymer (CFRP) possesses excellent tensile properties, good corrosion resistance, and fatigue resistance, making it a promising material for civil engineering applications. Considering these advantages, CFRP has become an ideal alternative to traditional steel, especially in long-span cable-stayed bridge systems. However, because CFRP is an anisotropic material, its radial compressive strength and interlaminar shear strength are relatively low, making it unsuitable for efficient anchoring using traditional anchorages.
[0003] Currently, existing anchorages for CFRP strands or reinforcing bars mainly include clamping, bonding, and composite types. Clamping anchorages are convenient to operate, have a short construction cycle, and are widely used. However, most current clamping anchorages directly clamp the CFRP strands or reinforcing bars with clamping plates, resulting in excessive compressive stress on the surface of the CFRP strands or reinforcing bars, causing CFRP damage and affecting anchoring efficiency. Furthermore, they are too bulky and inconvenient to use. Utility Model Content
[0004] To address the shortcomings of existing CFRP strand or reinforcement anchors, this invention designs a clamping anchor suitable for anchoring single CFRP strands or reinforcements. This design is not only compact but also ensures efficient anchoring of CFRP strands or reinforcements while reducing surface compressive stress on the CFRP.
[0005] The first aspect of this application provides a clamping anchor suitable for anchoring a single CFRP strand or reinforcing bar, comprising: a steel sleeve, a bolt, a clamp, and an aluminum sleeve; the steel sleeve is an inner conical sleeve with a reduced inner diameter and a constant outer diameter, and a thread is provided on a portion of the outer surface of the steel sleeve, the nut thread matches the outer thread of the steel sleeve, the clamp is an inner conical type with a constant inner diameter and a reduced outer diameter, and the aluminum sleeve is a straight cylindrical type with both the inner and outer diameters unchanged.
[0006] Furthermore, the inner cone angle of the steel sleeve is 3°.
[0007] Furthermore, the outer surface of the steel sleeve is provided with threads within 50mm of the free end, and the inner surface of the steel sleeve is smooth.
[0008] Furthermore, the inner cone angle of the clamping piece is 3.1°, that is, the inclination angle of the inner surface of the steel sleeve differs from the inclination angle of the outer surface of the clamping piece by 0.1°, and the free end of the clamping piece is a three-piece type, while the loading end of the clamping piece is an integral type.
[0009] Furthermore, the outer surface of the clip is smoothed, the inner surface is provided with serrated threads, and the remaining parts are roughened.
[0010] Furthermore, the free end of the aluminum sleeve is cut into three pieces, while the loading end is a complete circular tube.
[0011] Furthermore, the diameter of the aluminum sleeve is slightly larger than that of the CFRP stranded wire or reinforcing bar, and the outer surface of the aluminum sleeve is roughened and the inner surface is sandblasted.
[0012] Furthermore, an adhesive is applied to the surface of the anchoring area of the stranded wire or reinforcing bar. The adhesive is a high-strength structural adhesive, which has a fast curing time and high strength.
[0013] The technical solution provided in this application may include the following beneficial effects:
[0014] This application discloses a clamping anchor suitable for CFRP strands or reinforcing bars. The surface of the strands or reinforcing bars is coated with adhesive to increase the adhesion between them and the aluminum sleeve. The inner surface of the aluminum sleeve is sandblasted to increase the friction between the aluminum sleeve and the strands or reinforcing bars. The free end of the aluminum sleeve is separated to ensure uniform deformation during pre-tensioning and tension of the strands or reinforcing bars, reducing surface compressive stress. The loading end is intact to ensure easy installation of the aluminum sleeve. The inner surface of the clamping piece is provided with protruding threads, and the outer surface of the aluminum sleeve is roughened to increase the friction between the clamping piece and the aluminum sleeve. The loading end of the clamping piece is integral to ensure that the three-piece clamping pieces can simultaneously follow the tension during pre-tensioning and tension of the reinforcing bars, reducing the lateral shear stress of the strands or reinforcing bars. The inner surface of the steel sleeve and the outer surface of the clamping piece are smoothed to ensure that the clamping piece can enter the steel sleeve to the maximum extent during pre-tensioning and tension of the strands or reinforcing bars, increasing the clamping force. Through the above design, this application ensures high anchoring efficiency without damaging the strands or reinforcing bars.
[0015] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description
[0016] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.
[0017] Figure 1 This is an overall cross-sectional view of the clamping anchor shown in the embodiments of this application;
[0018] Figure 2 This is a schematic diagram of the aluminum sleeve in the clamping anchor shown in the embodiments of this application;
[0019] Figure 3 This is a schematic diagram of the clamping plate in the clamping anchor shown in the embodiments of this application;
[0020] Figure 4This is a schematic diagram of the steel sleeve in the clamping anchor shown in the embodiments of this application;
[0021] Figure 5 This is a schematic diagram of the clamping anchor after installation, as shown in the embodiments of this application.
[0022] Figure label:
[0023] In the diagram, CFRP stranded wire or reinforcing bar - 1, aluminum sleeve - 2, clamp - 3, steel sleeve - 4, bolt - 5, slotted aluminum sleeve - 21, integral aluminum sleeve - 22, outer surface of aluminum sleeve - 2a, inner surface of aluminum sleeve - 2b, three-piece clamp - 31, integral clamp - 32, outer surface of clamp - 3a, inner surface of clamp - 3b, free end of steel sleeve - 41, loading end of steel sleeve - 42, outer surface of steel sleeve - 4a, inner surface of steel sleeve - 4b. Detailed Implementation
[0024] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.
[0025] like Figure 1 As shown, a clamping anchor suitable for CFRP stranded wire or reinforcing bar includes five parts: stranded wire or reinforcing bar 1, aluminum sleeve 2, clamping plate 3, steel sleeve 4, and bolt 5.
[0026] like Figure 2 As shown, the aluminum sleeve 2 is 1mm thick, with different forms at both ends. The free end of the aluminum sleeve is a slit-type aluminum sleeve 21, which is cut into three pieces, each corresponding to an angle of 110°; the loaded end of the aluminum sleeve has a 10mm range of integral aluminum sleeve 22. The outer surface 2a of the aluminum sleeve is roughened, and the inner surface 2b of the aluminum sleeve is sandblasted. The diameter of the aluminum sleeve 2 is slightly larger than that of the reinforcing bar 1, and the length of the aluminum sleeve 2 is at least 10mm longer than the length of the clamping piece 3.
[0027] like Figure 3 As shown, the inner cone angle of the clamp 3 is 3.1°, and the two ends are of different forms. The free end of the clamp is a three-piece clamp 31, each piece corresponding to an angle of 110°; the loading end of the clamp is an integral clamp 32 within 10mm. The outer surface 3a of the clamp is smoothed, and the inner surface 3b of the aluminum sleeve is provided with a toothed thread. The distance of one revolution of the thread is equal to the lay pitch of the CFRP strand or the thread spacing is equal to the spacing of the CFRP ribs, with a height of 0.3mm. The remaining part is roughened.
[0028] like Figure 4As shown, the inner cone angle of the steel sleeve 4 is 3°, and both ends are round. Threads are provided within 50mm of the free end 41 on the outer surface 4a of the steel sleeve, with a thread pitch of 3mm. The threads of the bolt 5 match the threads of the steel sleeve 4. The inner surface 4b of the steel sleeve is smoothed.
[0029] During anchor installation, firstly, apply high-strength structural adhesive evenly to the anchorage area of the strand or reinforcing bar 1, then pass it through the aluminum sleeve 2, ensuring that the aluminum sleeve 2 completely wraps around the reinforcing bar 1; next, pass the installed strand or reinforcing bar 1 and aluminum sleeve 2 through the clamp 3, ensuring that the loading end of the aluminum sleeve is at least 10mm away from the loading end of the clamp; then, install the installed strand or reinforcing bar 1, aluminum sleeve 2, and clamp 3 as a whole into the steel sleeve 4; finally, apply a pre-tightening force to the free end 31 of the clamp to pre-tighten the anchor; after pre-tightening, the anchor is installed as follows. Figure 5 As shown. After installation, the strands or reinforcing bars 1 can be tensioned once the high-strength structural adhesive has fully cured.
[0030] The embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market of the various embodiments, or to enable others skilled in the art to understand the embodiments disclosed herein.
Claims
1. A clamping anchor suitable for CFRP stranded wire or reinforcing bar, characterized in that, include: The components include a steel sleeve, clamps, an aluminum sleeve, bolts, and stranded wire or reinforcing bars. The steel sleeve is an inner conical shape with a constant outer diameter and a decreasing inner diameter, and is threaded on its outer surface. The clamps have a decreasing outer diameter but a constant inner diameter, with the loaded end intact and the free end separated into three pieces. The aluminum sleeve has a constant outer and inner diameter, with the loaded end intact and the free end separated into three pieces. The bolts are threaded on their inner side, and the threads match the threads on the outer wall of the steel sleeve. The stranded wire or reinforcing bars pass through the aluminum sleeve and are fixed to the steel sleeve by the clamps.
2. The clamping anchorage suitable for CFRP stranded wire or reinforcing bar according to claim 1, characterized in that, The inner surface of the steel sleeve is smoothed, and the inclination angle of the inner surface of the steel sleeve differs from the inclination angle of the outer surface of the clamp by 0.1°; a thread is provided within 50mm of the outer surface of the free end of the steel sleeve, with a thread pitch of 3mm.
3. A clamping anchor suitable for CFRP stranded wire or reinforcing bar according to claim 1, characterized in that, The outer surface of the clamp is smoothed, and the inner surface of the clamp is provided with a toothed thread. The distance of one revolution of the thread is equal to the lay pitch of the CFRP strand or the thread spacing is equal to the rib spacing of the CFRP reinforcement. The clamping end is intact, while the free end is separated.
4. A clamping anchor suitable for CFRP stranded wire or reinforcing bar according to claim 1, characterized in that, The outer surface of the aluminum sleeve is roughened, and the inner surface is sandblasted; the loading end of the aluminum sleeve is intact, and the free end is separated; the length of the aluminum sleeve is at least 10mm longer than the length of the clamping piece; the inner diameter of the aluminum sleeve is slightly larger than the diameter of the stranded wire or reinforcing bar.
5. A clamping anchor suitable for CFRP stranded wire or reinforcing bar according to claim 1, characterized in that, High-strength structural adhesive is evenly applied to the anchoring area of the stranded wire or reinforcing bar.