CN119686492A - Embedded hybrid fiber threaded bar and manufacturing method thereof - Google Patents
Embedded hybrid fiber threaded bar and manufacturing method thereof Download PDFInfo
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- CN119686492A CN119686492A CN202411861045.8A CN202411861045A CN119686492A CN 119686492 A CN119686492 A CN 119686492A CN 202411861045 A CN202411861045 A CN 202411861045A CN 119686492 A CN119686492 A CN 119686492A
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Abstract
本发明提供一种嵌入式混杂纤维螺纹筋及其制造方法，嵌入式混杂纤维螺纹筋，包括核心轴向纤维束，所述核心轴向纤维束的外侧设置有固化成型的表层构造纤维束，所述表层构造纤维束的外侧设置有至少一条螺旋状的压痕槽，所述压痕槽的内部沿其固定设置有螺旋状的附加肋纤维束；本发明中的嵌入式混杂纤维螺纹筋，采用混杂纤维方案，根据性能需求，筋材中的核心轴向纤维束、表层构造纤维束、压痕槽等组成部分采用不同纤维种类，充分发挥不同纤维的性能特征，提高筋材的综合性能。
The present invention provides an embedded hybrid fiber threaded bar and a manufacturing method thereof. The embedded hybrid fiber threaded bar comprises a core axial fiber bundle, the outer side of the core axial fiber bundle is provided with a cured surface structural fiber bundle, the outer side of the surface structural fiber bundle is provided with at least one spiral indentation groove, and the inside of the indentation groove is fixedly provided with a spiral additional rib fiber bundle along the indentation groove. The embedded hybrid fiber threaded bar of the present invention adopts a hybrid fiber solution. According to performance requirements, the core axial fiber bundle, the surface structural fiber bundle, the indentation groove and other components in the reinforcement material adopt different fiber types, so as to give full play to the performance characteristics of different fibers and improve the comprehensive performance of the reinforcement material.
Description
Technical Field
The invention belongs to the technical field of FRP ribs, and particularly relates to an embedded hybrid fiber thread rib and a manufacturing method thereof.
Background
The carbon fiber composite material (CFRP) has the excellent performances of light weight, high strength, corrosion resistance, fatigue resistance and the like, is a novel high-performance structural material, can reduce the dead weight of the structure when being applied to a civil engineering structure, improves the performance and durability of the structure, and has good application prospect. In the form of ribbed bars, carbon fiber ribs can be used in place of steel bars in concrete structures and anchors.
Carbon fiber ribs are generally produced by a pultrusion process, and the production of high performance ribbed ribs still faces certain challenges, and the main ribbed rib processing forms at present are as follows:
1) The indentation rib is formed by winding release cloth before the fiber and the resin matrix pass through a die, stripping the release cloth after curing and forming, and forming a thread indentation, as disclosed in Chinese patent application with the application publication number of CN111945718A, a high-performance corrosion-resistant embossed FRP anchor rod and a preparation method thereof;
2) After extrusion, curing the thread rib, namely winding additional fibers after the fibers and the resin matrix are preformed, forming spiral dents on the surface by tightening, heating and curing the threads by an oven for molding, and finally removing the additional fibers to form spiral grooves;
3) Mechanical cutting of screw thread rib, namely, after the fiber and resin matrix are solidified and formed by a high-temperature die, forming screw thread dents by mechanical cutting, for example, the Chinese patent publication No. CN103225369B discloses a fiber composite rib with a screw thread structure on the surface and a preparation method thereof, and a pultrusion process is adopted.
The indentation rib and the post-extrusion curing thread rib can directly change the surface fiber orientation, so that the stress is unfavorable, the mechanical property of the whole rib is affected, meanwhile, for rib materials with larger diameters, the depth of the thread rib formed by the method is limited, the adhesion between the rib material and concrete is difficult to ensure, the surface fiber of the mechanically cut thread rib is directly cut off, and the residual fiber (rib) is only used for construction and cannot directly participate in the stress, so that the section of the rib material is weakened. In addition, due to the anisotropy of materials, the existing carbon fiber thread rib still has the problem of low shear strength.
In view of the technical challenges and limitations of the existing carbon fiber thread ribs, in order to meet engineering application, a novel fiber reinforced thread rib needs to be developed, the performance is improved, the material utilization rate is improved, and the production cost is reduced, so that a larger effect is exerted in practical application.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides the embedded hybrid fiber thread rib which improves the performance, improves the material utilization rate and reduces the production cost, thereby playing a larger role in practical application and a manufacturing method thereof.
The embedded hybrid fiber thread comprises a core axial fiber bundle, wherein a solidified surface layer structure fiber bundle is arranged on the outer side of the core axial fiber bundle, at least one spiral indentation groove is formed on the outer side of the surface layer structure fiber bundle, and a spiral additional rib fiber bundle is fixedly arranged in the indentation groove along the indentation groove.
Further, the core axial fiber bundles are carbon fiber bundles, the surface layer structure fiber bundles are glass fiber bundles, basalt fiber bundles or aramid fiber bundles, and the additional rib fiber bundles are carbon fiber bundles, glass fiber bundles or basalt fiber bundles.
Further, the depth h0 of the indentation groove is 0.1-0.5 mm, the thickness t1 of the surface layer structure fiber bundle is 0.5-1 cm, and the height hr of the additional rib fiber bundle protruding out of the surface layer structure fiber bundle surface is 0.08-0.15 times of the outer diameter d1 of the surface layer structure fiber bundle.
Further, the cross section of the additional rib fiber bundle is triangular, rectangular or trapezoidal.
The manufacturing method of the embedded hybrid fiber thread rib comprises the following steps:
S1, after the core axial fiber bundles and the surface layer structure fiber bundles are soaked by resin, preforming by a circular preforming die to obtain a preformed circular bar;
S2, spirally winding a demolding cloth belt on the surface of the preformed round bar, and then, curing and forming through a round forming die to obtain the round bar;
s3, after the round bar is demolding, gradually removing the demolding cloth belt, and forming a spiral indentation groove on the surface of the round bar;
S4, winding and embedding the additional rib fiber bundles into the spiral indentation groove after the additional rib fiber bundles are soaked by resin, enabling the additional rib fiber bundles to protrude out of the surface layer structure fiber bundle surface for a height hr, and then curing by an oven.
Further, in the step S2, at least two demolding cloth belts are uniformly and alternately wound on the surface of the preformed round bar;
in the step S3, after the round bar is demolding, the demolding cloth belt is gradually removed, and at least two uniformly staggered spiral indentation grooves are formed on the surface of the round bar.
Further, in the step S2, the included angle theta between the demolding cloth belt and the preformed round bar bracket is 45-70 degrees.
S11, after the core axial fiber bundles are infiltrated by resin, curing and preforming the core axial fiber bundles by a first circular preforming die with the aperture of d0 and a first forming die to obtain a circular bar of the core fiber bundles;
S12, after the surface layer structure fiber bundles are infiltrated by resin, the surface layer structure fiber bundles are distributed on the periphery of the core fiber bundle round bar in the S11, and the surface layer structure fiber bundles are preformed on the outer side of the core axial fiber bundles preformed in the S11 by a second preforming die with the aperture of d1, so that the preformed round bar is obtained.
Further, S4 is replaced by the fact that the additional rib fiber bundles are made of thermoplastic fiber composite materials, the thermoplastic fiber composite materials are heated and softened through a heating die, the thermoplastic fiber composite materials are formed into the shape of the additional rib fiber bundles, then the additional rib fiber bundles are wound, adhered and embedded in the spiral indentation grooves, and then natural cooling and solidification are carried out.
Further, the core axial fiber bundles are carbon fiber bundles, the surface layer structure fiber bundles are glass fiber bundles, basalt fiber bundles or aramid fiber bundles, and the additional rib fiber bundles are carbon fiber bundles, glass fiber bundles or basalt fiber bundles.
The invention has the beneficial effects that:
(1) According to the embedded hybrid fiber thread rib, a hybrid fiber scheme is adopted, and according to performance requirements, different fiber types are adopted for the components such as a core axial fiber bundle, a surface layer structure fiber bundle, an indentation groove and the like in the rib, so that the performance characteristics of different fibers are fully exerted, and the comprehensive performance of the rib is improved;
(2) The core axial fiber bundles and the surface layer structure fiber bundles form a rib body, and the indentation grooves only change the orientation of the surface layer structure fiber bundles and do not influence the exertion of the stress performance of the core axial fiber bundles;
(3) The additional rib fiber bundles are wound and embedded in the preformed indentation groove and form mechanical engagement with the surface layer structural fiber bundles, so that the overall adhesive force between the additional rib fiber bundles and the surface of the reinforcement material can be greatly improved, the slipping of the additional rib fiber bundles can be avoided, and the adhesive property between the thread ribs and the concrete is improved;
(4) The additional rib fiber bundles are wound on the outer sides of the core axial fiber bundles and the surface layer structure fiber bundles to form constraint on the core axial fiber bundles and the surface layer structure fiber bundles, and form a certain included angle with the longitudinal core axial fiber bundles and the surface layer structure fiber bundles all the time, so that the transverse shear strength of the rib material can be improved;
(5) The rib material main body formed by the core axial fiber bundles and the surface layer structural fiber bundles is cured in the die, so that the forming quality of axial force fibers can be effectively ensured;
(6) The core axial fiber bundles and the surface layer structure fiber bundles are molded step by step, so that the core axial fiber bundles do not generate radial deformation in the indentation groove molding process, the core axial fiber orientation is ensured, and the stretching performance of the core fiber bundles is fully exerted.
Drawings
Fig. 1 is a schematic structural view of an embedded hybrid fiber thread rib in the present invention.
Fig. 2 is a schematic cross-sectional structure of an embedded hybrid fiber screw according to the present invention.
Fig. 3 is a schematic view of the structure of the surface layer structured fiber bundle at the indentation groove in the present invention.
Fig. 4 is a schematic cross-sectional structure of an embedded hybrid fiber thread rib according to the present invention.
Fig. 5 is a schematic view of a manufacturing process of the embedded hybrid fiber screw according to the present invention.
Fig. 6 is a schematic view of another manufacturing process of the embedded hybrid fiber screw according to the present invention.
Fig. 7 is a schematic view of another manufacturing process of the embedded hybrid fiber screw according to the present invention.
Fig. 8 is a schematic structural view of a double-thread hybrid fiber screw according to the present invention.
Detailed Description
Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative, and is in no way intended to limit the invention, its application, or uses. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It should be noted that the relative arrangement of parts and steps, the composition of materials, numerical expressions and numerical values set forth in these embodiments should be construed as exemplary only and not limiting unless otherwise specifically stated.
The terms "first," "second," and the like, as used herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises" and the like means that elements preceding the word encompass the elements recited after the word, and not exclude the possibility of also encompassing other elements. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.
In the embodiment, the embedded hybrid fiber thread rib comprises a core axial fiber bundle 1, a solidified surface layer structure fiber bundle 2 is arranged on the outer side of the core axial fiber bundle 1, at least one spiral indentation groove 3 is arranged on the outer side of the surface layer structure fiber bundle 2, a spiral additional rib fiber bundle 4 is fixedly arranged in the indentation groove 3 along the indentation groove, according to performance requirements, different fiber types are adopted for the components of the core axial fiber bundle 1, the surface layer structure fiber bundle 2, the indentation groove 3 and the like in the rib material, the performance characteristics of different fibers are fully exerted, the comprehensive performance of the rib material is improved, the core axial fiber bundle 1 and the surface layer structure fiber bundle 2 form a rib material main body, the indentation groove 3 only changes the orientation of the surface layer structure fiber bundle 2, the stress performance of the core axial fiber bundle 1 is not influenced, the additional rib fiber bundle 4 is wound and embedded in the preformed indentation groove 3, the mechanical force between the additional rib fiber bundle 4 and the surface of the rib material is greatly improved, the additional rib fiber bundle 4 can be prevented from slipping off, the adhesive force between the additional rib fiber bundle 4 and the surface of the rib material surface can be prevented from being formed, and the axial fiber bundle 1 and the surface layer structure fiber bundle 2 can be always in a certain included angle with the axial direction of the core axial fiber bundle 2, and the fiber bundle 2 is axially constrained by the fiber bundle 2, and the fiber bundle 2 is formed by the fiber bundle 2 is axially and the fiber bundle is axially constrained by the fiber bundle 2.
In some embodiments, as a specific implementation mode of the core axial fiber bundle 1, the core axial fiber bundle 1 is a carbon fiber bundle, the core axial fiber bundle 1 and the surface layer structure fiber bundle 2 form a rib body, the indentation groove 3 only changes the orientation of the surface layer structure fiber bundle 2, the stress performance of the core axial fiber bundle 1 is not affected, the core axial fiber bundle 1 is made of high-performance carbon fibers, and the core axial fiber bundle 1 is used as a main axial stress part, so that the high performance of the carbon fibers can be fully exerted.
In some embodiments, as a specific implementation manner of the surface layer structural fiber bundle 2, the surface layer structural fiber bundle 2 is a glass fiber bundle, a basalt fiber bundle or an aramid fiber bundle, on one hand, the characteristics of low carbon fiber modulus, high elongation, good wear resistance, good impact resistance and the like of the fiber such as the glass fiber bundle, the basalt fiber bundle or the aramid fiber bundle are utilized, on the other hand, the comprehensive performance (such as better wear resistance, impact resistance, coiling performance and the like) of the thread rib can be improved, and on the other hand, the cost of the fiber is lower, and the material cost of the thread rib can be reduced.
In some embodiments, as a specific implementation of the additional rib fiber bundle 4, the additional rib fiber bundle 4 is a carbon fiber bundle, a glass fiber bundle, or a basalt fiber bundle.
In some embodiments, as shown in fig. 2 and 4, the depth h0 of the indentation groove is 0.1 to 0.5mm, preferably, the depth h0 of the indentation groove 3 is 0.3mm, the thickness t1 of the surface layer structure fiber bundle is 0.5 to 1cm, the height hr of the surface of the additional rib fiber bundle protruding out of the surface layer structure fiber bundle is 0.08 to 0.15 times the outer diameter d1 of the surface layer structure fiber bundle, the outer diameter d0 of the core axial fiber bundle 1, the thickness t1 of the surface layer structure fiber bundle 2, and the outer diameter d1 of the surface layer structure fiber bundle 2 is d1=d0+2t1.
In some embodiments, the pitch of the spiral indentation groove 3 is 10-30 mm, specifically, the pitch of the spiral indentation groove 3 is 10mm, 15mm, 20mm, 25mm, 30mm, and preferably, the pitch of the spiral indentation groove 3 is 20mm.
In some embodiments, the cross section of the additional rib fiber bundles 4 is triangular, rectangular or trapezoidal, the cross section of the additional rib fiber bundles 4 is not limited to the three cases listed above, and in practical application, the additional rib fiber bundles 4 can be further personalized designed to adapt to the anchoring requirements of different concrete structures.
In some embodiments, at least two uniformly staggered spiral indentation grooves 3 are formed on the surface of the surface layer structural fiber bundle 2, so that at least two uniformly staggered spiral additional rib fiber bundles 4 can be arranged on the surface of the surface layer structural fiber bundle 2, and double-thread hybrid fiber thread tendons and multi-thread hybrid fiber thread tendons as shown in fig. 8 are formed, so that the tendons have a plurality of spiral additional rib fiber bundles 4 on the same section, and the tendon performance is further improved.
In some embodiments, as shown in fig. 5, a method for manufacturing an embedded hybrid fiber thread bar is disclosed, comprising the steps of:
s1, after a core axial fiber bundle 1 and a surface layer construction fiber bundle 2 are soaked by resin, preforming by a circular preforming die 6 to obtain a preformed circular bar;
S2, spirally winding a demolding cloth belt 7 on the surface of the preformed round bar, and then curing and forming through a round forming die 8 to obtain the round bar;
s3, after the round bar is demolding, gradually removing the demolding cloth belt 7, and forming a spiral indentation groove 3 on the surface of the round bar;
s4, winding and embedding the additional rib fiber bundles 4 into the spiral indentation groove 3 after the additional rib fiber bundles 4 are soaked by resin, and making the additional rib fiber bundles 4 protrude out of the surface layer construction fiber bundles 2 by a height hr, and then curing through the oven 9.
In the embodiment, the rib material body formed by the core axial fiber bundles 1 and the surface layer construction fiber bundles 2 is cured in the die, so that the forming quality of axial force fibers can be effectively ensured, and the additional rib fiber bundles are bonded and cured by a post-curing process, so that the sectional shape of the additional rib is flexibly designed.
In some embodiments, at least two demolding cloth belts are uniformly and alternately wound on the surface of the preformed round bar in S2, after the round bar is demolding in S3, gradually removing the demolding cloth belts to form at least two uniformly and alternately spiral indentation grooves on the surface of the round bar, and at least two uniformly and alternately spiral indentation grooves 3 are formed on the surface of the surface layer structural fiber bundle 2, so that at least two uniformly and alternately spiral additional rib fiber bundles 4 can be arranged on the surface of the surface layer structural fiber bundle 2, and double-thread hybrid fiber thread ribs and multi-thread hybrid fiber thread ribs can be formed.
As a specific implementation mode of the embodiment, the thermoplastic fiber composite material is heated and softened by the heating die 10 and is formed into a shape with a triangular, rectangular or trapezoidal section, and the additional rib scheme of the thermoplastic fiber composite material can conveniently realize the molding of the additional ribs with different shapes so as to meet different performance requirements, meanwhile, the heating and curing process of an oven can be saved, and the processing cost is reduced.
In S2, the included angle theta between the demolding cloth belt and the preformed round bar bracket is 45-70 degrees,Wherein d1 is the outer diameter of the surface layer structured fiber bundle 2, dr is the pitch of the threads on the ribs, θ may be 65 ° when a single thread is employed, and θ may be 50 ° when a double thread is employed.
In some embodiments, as shown in fig. 7, S1 may be replaced with:
S11, after the core axial fiber bundle 1 is infiltrated by resin in the impregnating tank 5, curing and preforming the core axial fiber bundle by a first circular preforming die 61 and a first forming die 81 with the aperture of d0 to obtain a circular core fiber bundle bar;
S12, after the surface layer structure fiber bundle 2 is soaked in resin in the soaking tank 5, the surface layer structure fiber bundle 2 is distributed on the periphery of the round bar of the core fiber bundle in S11, and is solidified and preformed on the outer side of the preformed core axial fiber bundle 1 in S11 through a second preforming die 62 with the aperture of d1, so that a preformed round bar is obtained;
And S11, primarily solidifying the core axial fiber bundle, so that the core axial fiber bundle does not generate radial deformation in the subsequent pultrusion process, and ensuring the fiber orientation of the part so as to fully exert the performance of the carbon fiber of the core part.
In some embodiments, as shown in FIG. 6, S4 is replaced by using a thermoplastic fiber composite material as the additional rib fiber bundle, heating the thermoplastic fiber composite material by a heating mold 10 to soften the thermoplastic fiber composite material, forming the thermoplastic fiber composite material into the shape of the additional rib fiber bundle, winding and bonding the additional rib fiber bundle into the spiral indentation groove 3, and naturally cooling and solidifying the additional rib fiber bundle.
As a specific implementation manner of the above example, the core axial fiber bundle 1 is a carbon fiber bundle, the surface layer structure fiber bundle 2 is a glass fiber bundle, a basalt fiber bundle or an aramid fiber bundle, and the additional rib fiber bundle 4 is a carbon fiber bundle, a glass fiber bundle or a basalt fiber bundle.
As a specific implementation mode of the embodiment, in the S2, the thickness of the demolding cloth belt is 0.1-0.5 mm, the width of the demolding cloth belt is 5mm, and the thickness of the demolding cloth belt is 0.3mm, and the width of the demolding cloth belt is 5mm.
Thus, various embodiments of the present invention have been described in detail. In order to avoid obscuring the concepts of the invention, some details known in the art have not been described. How to implement the solutions disclosed herein will be fully apparent to those skilled in the art from the above description.
The above examples only represent some embodiments of the invention, which are described in more detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.
Claims (10)
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| Application Number | Priority Date | Filing Date | Title |
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| CN202411861045.8A CN119686492A (en) | 2024-12-17 | 2024-12-17 | Embedded hybrid fiber threaded bar and manufacturing method thereof |
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| CN202411861045.8A CN119686492A (en) | 2024-12-17 | 2024-12-17 | Embedded hybrid fiber threaded bar and manufacturing method thereof |
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| CN119686492A true CN119686492A (en) | 2025-03-25 |
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