High modulus hybrid fiber reinforced resin strand, method of making and use thereof

Abstract

The application provides a high-modulus hybrid fiber reinforced resin bar and a preparation method and application thereof, relates to the technical field of building materials, and comprises a hybrid fiber reinforced bar as a core, a resin layer wrapping the core, and a fiber reinforced polymer bar winding the resin layer; wherein the volume ratio of carbon fibers and glass fibers in the hybrid fiber reinforced bar as the core is 1:2-1:6, the elastic modulus of the glass fibers is 90-120 GPa, the elastic modulus of the carbon fibers is 230-460 GPa, and the fiber volume fraction of the hybrid fiber reinforced bar as the core is 60-75%. The application solves the technical problems of low modulus and poor mechanical properties of the HFRP bar in the prior art, and achieves the technical effects of high elastic modulus, good toughness and strong compression resistance of the HFRP bar.

Description

Technical Field

[0001] This invention relates to the technical field of building materials, and in particular to a high-modulus hybrid fiber reinforced resin bar, its preparation method, and its application. Background Technology

[0002] Fiber-reinforced polymer (FRP) composites are widely used in civil engineering as a substitute for steel due to their advantages such as lightweight, high strength, corrosion resistance, fatigue resistance, and non-magnetic properties. Compared with traditional steel bars, glass fiber reinforced polymer (GFRP) composite steel bars have excellent durability. Furthermore, FRP bars, used as longitudinal reinforcement, web reinforcement, or prestressed tendons in concrete structures, not only improve the durability of concrete structures but also bring significant economic and social benefits.

[0003] Currently, each FRP material has its own drawbacks. For example, carbon fiber reinforced polymer (CFRP) bars are too expensive and have low elongation, making them difficult to use on a large scale. On the other hand, glass fiber reinforced polymer (GFRP) bars, which are cheaper, have a low modulus of elasticity, resulting in low stiffness of concrete members using GFRP bars, which can easily cause cracks and excessive deformation, leading to damage.

[0004] To address the aforementioned issues, current research primarily utilizes high-modulus reinforced polymer (HFRP) reinforcement made from a blend of multiple fibers to improve mechanical properties. This approach not only combines the advantages of various fibers to achieve a yield stage similar to that of steel reinforcement but also significantly reduces material costs. However, the elastic modulus of glass fiber materials used in existing studies is mostly below 80 GPa, and the elastic modulus of carbon fiber is generally below 230 GPa. Consequently, the HFRP reinforcement produced also falls below 90 GPa, highlighting the significant issue of low modulus. Furthermore, current conventional processes cannot mitigate the anisotropy of the reinforcement, including its complex behavior under compression and the lack of standardized testing procedures. These processes often overlook the reinforcement's contribution to compressive strength in the concrete compression zone, hindering its use as a compressive reinforcement material. Therefore, producing high-modulus HFRP reinforcement with excellent performance across various aspects is a crucial problem urgently needing to be solved in the construction industry.

[0005] In view of this, the present invention is hereby proposed. Summary of the Invention

[0006] One of the objectives of this invention is to provide a high-modulus hybrid fiber reinforced resin bar that not only has high elastic modulus and good toughness, but also strong compressive strength.

[0007] The second objective of this invention is to provide a method for preparing high-modulus hybrid fiber reinforced resin bars, which is simple, efficient, and suitable for factory production.

[0008] The third objective of this invention is to provide an application of high-modulus hybrid fiber-reinforced resin bars, which can improve the stiffness of concrete components, reduce the risk of damage, and achieve outstanding application results.

[0009] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0010] In a first aspect, a high-modulus hybrid fiber reinforced resin bar includes a hybrid fiber reinforced bar as a core, a resin layer enclosing the core, and a fiber reinforced polymer bar wrapped around the resin layer.

[0011] The volume ratio of carbon fiber to glass fiber in the hybrid fiber reinforcing bar that serves as the core is 1:2 to 1:6.

[0012] The elastic modulus of the glass fiber is 90-120 GPa, and the elastic modulus of the carbon fiber is 230-460 GPa.

[0013] The fiber volume fraction of the hybrid fiber reinforcing rib, which serves as the core, is 60-75%.

[0014] Furthermore, the glass fiber includes E9 glass fiber;

[0015] Preferably, the carbon fiber comprises M40JB-12000 type high modulus carbon fiber.

[0016] Furthermore, the resin layer comprises a vinyl resin;

[0017] Preferably, the elastic modulus of the vinyl resin is above 3 GPa;

[0018] Preferably, the thickness of the resin layer is 2 to 3 mm.

[0019] Furthermore, the winding includes helical winding;

[0020] Preferably, the spiral winding angle is 80-85°.

[0021] Furthermore, the fiber-reinforced polymer reinforcement includes glass fiber-reinforced polymer reinforcement;

[0022] Preferably, the modulus of the glass fiber reinforced polymer bar is 90–120 GPa.

[0023] Secondly, a method for preparing high-modulus hybrid fiber reinforced resin reinforcement as described in any one of the above claims includes the following steps:

[0024] (a) Carbon fiber and glass fiber are drawn out in proportion, and then subjected to first impregnation and molding in sequence to obtain a hybrid fiber reinforcement as the core.

[0025] (b) The hybrid fiber reinforcing bar obtained in step (a) as the core is impregnated with resin in a second time to form a resin layer. Then, the fiber-reinforced polymer bar is wound around the resin layer and cured to obtain the high-modulus hybrid fiber-reinforced resin bar.

[0026] Furthermore, the molding method includes extrusion molding in a mold.

[0027] Furthermore, the crosslinking initiator of the resin layer includes at least one of benzoyl peroxide and tert-butyl peroxide;

[0028] Preferably, the crosslinking initiator is a two-component composite initiator of benzoyl peroxide and tert-butyl peroxide.

[0029] Furthermore, the winding method includes the following steps:

[0030] The hybrid fiber reinforcement is spirally wound on the resin layer along the axial direction.

[0031] Thirdly, the application of any of the above-mentioned high-modulus hybrid fiber-reinforced resin bars in concrete members.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects:

[0033] The high-modulus hybrid fiber-reinforced resin (HFRP) bar provided by this invention effectively improves the elastic modulus of the HFRP bar through the hybridization of high-modulus carbon glass fibers. Simultaneously, the overall compressive strength of the HFRP bar is significantly enhanced by the externally wound fiber-reinforced polymer (e.g., high-modulus GFRP), nearly doubling its compressive strength. Furthermore, the resin layer can be made of a high-modulus, high-toughness resin material, further strengthening the toughness of the HFRP bar. In summary, through the synergistic effect of the specific modulus and proportion of carbon and glass fibers in the hybrid fibers, the specific fiber volume fraction, and the fiber-reinforced polymer winding in the resin layer, the HFRP bar of this invention not only has high elastic modulus and good toughness but also strong compressive strength, exhibiting excellent performance across the board. It is highly suitable as a building material, meeting the needs of the construction industry.

[0034] The method for preparing high-modulus hybrid fiber reinforced resin bars provided by this invention is simple, efficient, and suitable for factory production.

[0035] The application of high-modulus hybrid fiber-reinforced resin bars provided by this invention can improve the stiffness of concrete components, making them less prone to damage, and the application effect is outstanding. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a cross-sectional view of the high-modulus hybrid fiber-reinforced resin bar provided in Embodiment 1 of the present invention;

[0038] Figure 2 This is a cross-sectional view of the high-modulus hybrid fiber reinforced resin bar provided in Embodiment 1 of the present invention;

[0039] Figure 3 The stress-strain relationship diagrams for CFRP, HFRP, and GFRP bars provided in Embodiment 1 of the present invention are shown. Detailed Implementation

[0040] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] According to a first aspect of the present invention, a high-modulus hybrid fiber reinforced resin bar is provided, comprising a hybrid fiber reinforced bar as a core, a resin layer enclosing the core, and a fiber reinforced polymer bar wound around the resin layer;

[0042] In the hybrid fiber reinforcement, the volume ratio of carbon fiber to glass fiber in the core can be 1:2 to 1:6, with typical but non-limiting volume ratios being 1:2, 1:3, 1:4, 1:5, and 1:6. If the volume ratio of carbon fiber to glass fiber (carbon-glass ratio) is too small, it will result in low stiffness; if the volume ratio of carbon fiber to glass fiber (carbon-glass ratio) is too large, it will result in poor ductility.

[0043] The elastic modulus of glass fiber can be 90–120 GPa, with typical but non-limiting elastic moduli being 90 GPa, 95 GPa, 100 GPa, 105 GPa, 110 GPa, 115 GPa, and 120 GPa. If the elastic modulus of glass fiber is too small, it will result in low stiffness of the hybrid fiber reinforced tendon; if the elastic modulus of glass fiber is too large, it will result in poor ductility of the hybrid fiber reinforced tendon.

[0044] The elastic modulus of carbon fiber can range from 230 to 460 GPa. Typical but non-limiting elastic moduli include 230 GPa, 250 GPa, 270 GPa, 290 GPa, 300 GPa, 310 GPa, 320 GPa, 330 GPa, 340 GPa, 350 GPa, 360 GPa, 370 GPa, 380 GPa, 390 GPa, 400 GPa, 420 GPa, 440 GPa, and 460 GPa. If the elastic modulus of carbon fiber is too low, it will result in low stiffness of the hybrid fiber reinforcement; if the elastic modulus of carbon fiber is too high, it will result in poor ductility of the hybrid fiber reinforcement.

[0045] The fiber volume fraction of the hybrid fiber reinforcement used as the core can be 60% to 75%, with typical but not limiting fiber volume fractions being 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, and 75%. If the fiber volume fraction is too small, the hybrid fiber reinforcement will have low stiffness; if the fiber volume fraction is too large, the surface of the hybrid fiber reinforcement will become rough, affecting its load-bearing performance.

[0046] The high-modulus hybrid fiber-reinforced resin (HFRP) bar provided by this invention effectively improves the elastic modulus of the HFRP bar through the hybridization of high-modulus carbon glass fibers. Simultaneously, the overall compressive strength of the HFRP bar is significantly enhanced by the externally wound fiber-reinforced polymer (e.g., high-modulus GFRP), nearly doubling its compressive strength. Furthermore, the resin layer can be made of a high-modulus, high-toughness resin material, further strengthening the toughness of the HFRP bar. In summary, through the synergistic effect of the specific modulus and proportion of carbon and glass fibers in the hybrid fibers, the specific fiber volume fraction, and the fiber-reinforced polymer winding in the resin layer, the HFRP bar of this invention not only has high elastic modulus and good toughness but also strong compressive strength, exhibiting excellent performance across the board. It is highly suitable as a building material, meeting the needs of the construction industry.

[0047] In a preferred embodiment, the glass fiber includes, but is not limited to, E9 glass fiber with an elastic modulus of 90 to 120 GPa; the carbon fiber includes, but is not limited to, M40JB-12000 type high modulus (230 to 460 GPa) carbon fiber.

[0048] The high-modulus E9 glass fiber and M40JB-12000 high-modulus carbon fiber selected in this invention are more conducive to improving the elastic modulus of HFRP bars, so as to meet the needs of the construction industry.

[0049] In a preferred embodiment, the resin layer includes, but is not limited to, vinyl ester resin, which has good chemical stability, corrosion resistance and good adhesion to fibers, and a viscosity at 25°C suitable for impregnation of continuous fibers. It is further preferred to be a vinyl ester resin with high modulus and high toughness, and its elastic modulus can be above 3 GPa, which is beneficial to further enhance the toughness of HFRP bars.

[0050] In this invention, the thickness of the resin layer can be 2 to 3 mm, for example, 2 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, or 3 mm, but is not limited thereto.

[0051] In a preferred embodiment, the fiber-reinforced polymer strands are wound around the resin layer in a manner including, but not limited to, spiral winding.

[0052] In a preferred embodiment, the spiral winding angle can be 80 to 85°, for example, 80°, 81°, 82°, 83°, 84°, or 85°, but is not limited thereto.

[0053] In a preferred embodiment, the fiber-reinforced polymer bar includes, but is not limited to, glass fiber reinforced polymer bar (GFRP), and its modulus can be 90 to 120 GPa, for example, 90 GPa, 95 GPa, 100 GPa, 105 GPa, 110 GPa, 115 GPa, 120 GPa, but is not limited thereto.

[0054] This invention uses high-modulus GFRP reinforcement spirally wound around the core HFRP reinforcement at a specific angle to form a GFRP layer, creating a transverse semi-enclosed structure, thereby improving the overall compressive strength of the reinforcement material, increasing its compressive strength by nearly 100%.

[0055] According to a second aspect of the present invention, a method for preparing high-modulus hybrid fiber reinforced resin bars as described in any one of the preceding claims is provided, comprising the following steps:

[0056] (a) Carbon fiber and glass fiber are drawn out in proportion, and then subjected to first impregnation and molding in sequence to obtain a hybrid fiber reinforcement as the core.

[0057] (b) The hybrid fiber reinforcement obtained in step (a) is impregnated with resin in a second time to form a resin layer. Then, the fiber-reinforced polymer reinforcement is wound around the resin layer and cured to obtain a high-modulus hybrid fiber-reinforced resin reinforcement.

[0058] The method for preparing high-modulus hybrid fiber reinforced resin bars provided by this invention is simple, efficient, and suitable for factory production.

[0059] In a preferred embodiment, in step (a), the molding method includes, but is not limited to, extrusion molding in a mold.

[0060] In a preferred embodiment, in step (b), the crosslinking initiator of the resin layer includes, but is not limited to, at least one of benzoyl peroxide (BPO) and tert-butyl peroxide (TBPB), and may be further preferred as a two-component composite initiator of benzoyl peroxide (BPO) and tert-butyl peroxide (TBPB).

[0061] This invention employs a two-component composite initiation system composed of benzoyl peroxide and tert-butyl peroxide to activate the crosslinking reaction of vinyl resins, thereby accelerating the curing of the resins.

[0062] In a preferred embodiment, the winding method includes the following steps:

[0063] The hybrid fiber reinforcement is spirally wound on the resin layer along the axial direction.

[0064] A typical preparation method for high-modulus hybrid fiber reinforced resin bars includes the following steps:

[0065] Step 1: Yarn feeding: Carbon fiber and glass fiber are drawn out from the yarn frame in proportion to obtain fibers, which are then ready for use;

[0066] Step 2: First impregnation: Fibers (carbon-glass ratio of 1:2 to 1:6) enter the impregnation tank through a threading plate with uniformly arranged round holes. The impregnation tank is heated by a water bath to improve the fluidity of the resin, thereby fully impregnating the fibers and obtaining impregnated fiber bundles.

[0067] Step 3: Molding: The impregnated fiber bundles pass through the yarn threading plate and enter the molding die through the peripheral holes of the molding die with a circular cross-section. In the molding die, they are extruded (pultrusion-compression molding process) to initially form a smooth round HFRP rib (as a hybrid fiber reinforcement in the core, the fibers are dispersed and the fiber volume fraction is 60-75%).

[0068] Step 4: Second impregnation: The round HFRP reinforcing bar is fully impregnated in the impregnation tank to form a resin layer with a thickness of 2-3 mm;

[0069] Step 5: Wrapping: The high-modulus GFRP reinforcement is spirally wound on the resin layer at an angle of 80-85° along the axial direction of the HFRP reinforcement to form a semi-wrapped structure, thus obtaining the wrapped reinforcement.

[0070] Step 6: The wrapped reinforcing material is heated and cured through a heating channel to obtain a high-modulus hybrid fiber-reinforced resin reinforcing bar product.

[0071] The preparation method provided by this invention employs a pultrusion-compression molding process, using a carbon-to-glass ratio of 1:2 to 1:6, a fiber volume fraction of 60 to 75%, and dispersed fiber distribution to prepare HFRP reinforcement as the core, which effectively improves the elastic modulus of fiber-reinforced composite reinforcement. An additional GFRP layer is formed around the core HFRP reinforcement using a helical winding method, creating a semi-enclosed structure, which is then cured by heating, significantly improving the overall compressive strength of the HFRP reinforcement. The preparation method of this invention is simple, yields a high rate of excellent finished products, and is suitable for industrial production.

[0072] According to a third aspect of the present invention, the application of the high modulus hybrid fiber reinforced resin bar described in any of the preceding claims in concrete members is provided.

[0073] The application of high-modulus hybrid fiber-reinforced resin bars provided by this invention can improve the stiffness of concrete components, making them less prone to damage, and the application effect is outstanding.

[0074] The present invention will be further illustrated by the following examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0075] Example 1

[0076] A high-modulus hybrid fiber-reinforced resin bar (see front section view) Figure 1 See cross-sectional view Figure 2 The product includes a hybrid fiber reinforced rib (HFRP rib) as the core, a resin layer that wraps the core, and a high modulus (modulus of 90 to 120 GPa) glass fiber reinforced polymer (GFRP) rib that is spirally wound on the resin layer along the axial direction of the HFRP rib.

[0077] The hybrid fiber reinforcement, which serves as the core, is mainly composed of CFRP and GFRP reinforcements. The volume ratio of carbon fiber to glass fiber in the hybrid fiber reinforcement is 1:4, and the fiber volume fraction is 65%.

[0078] Among them, the elastic modulus of glass fiber (E9 glass fiber) is 120 GPa, and the elastic modulus of carbon fiber (M40JB-12000 high modulus carbon fiber) is 380 GPa.

[0079] The resin layer (3mm thick) is made of high-elasticity vinyl resin and epoxy resin, with an elastic modulus of 3GPa.

[0080] In this embodiment, the stress-strain relationship of the HFRP reinforcement was tested against that of the CFRP and GFRP reinforcements. The results are shown in [the table below]. Figure 3 It can be seen that HFRP bars have better ductility than CFRP bars, higher modulus than GFRP bars, and HFRP bars have a yield plateau.

[0081] The stress-strain relationship is tested using a tensile test on reinforcing bars.

[0082] Example 2-3

[0083] The difference between Examples 2-3 and Example 1 is that the volume ratios of carbon fiber and glass fiber in the hybrid fiber reinforced ribs of Examples 2-4 are 1:2 and 1:6, respectively, while the rest are the same as in Example 1.

[0084] Examples 4-6

[0085] The difference between Examples 4-6 and Example 1 is that the fiber volume fraction of the hybrid fiber reinforcing ribs used as the core in Examples 4-6 is 60%, 70%, and 75%, respectively, while the rest is the same as in Example 1.

[0086] Examples 7-8

[0087] The difference between Examples 7-8 and Example 1 is that the elastic modulus of E9 glass fiber in Examples 7-8 is 90 GPa and 100 GPa, respectively, while the rest is the same as in Example 1.

[0088] Examples 9-11

[0089] The difference between Examples 9-11 and Example 1 is that the elastic modulus of M40JB-12000 high-modulus carbon fiber in Examples 9-11 is 230GPa, 350GPa and 460GPa respectively, while the rest are the same as in Example 1.

[0090] Examples 12-13

[0091] The difference between Examples 12-13 and Example 1 is that the thickness of the resin layer in Examples 12-13 is 2 mm and 2.5 mm, respectively, while the rest is the same as in Example 1.

[0092] Example 14

[0093] This embodiment describes a method for preparing high-modulus hybrid fiber reinforced resin bars as described in Examples 1-13, including the following steps:

[0094] Step 1: Yarn feeding: Carbon fiber and glass fiber are drawn out from the yarn frame in proportion to obtain fibers, which are then ready for use;

[0095] Step 2: First impregnation: The fibers enter the impregnation tank through a yarn-threading plate with uniformly arranged round holes. The impregnation tank is heated by a water bath to improve the fluidity of the resin, so that the fibers are fully impregnated to obtain impregnated fiber bundles.

[0096] Step 3: Molding: The impregnated fiber bundles pass through the yarn threading plate and enter the molding die through the peripheral holes of the molding die with a circular cross-section. In the molding die, they are extruded (pultrusion-compression molding process) to initially form smooth round HFRP ribs.

[0097] Step 4: Second impregnation: The round HFRP reinforcing bar is fully impregnated in the impregnation tank to form a resin layer (vinyl resin) of a certain thickness;

[0098] Among them, a two-component composite initiator of benzoyl peroxide and tert-butyl peroxide is used to activate the crosslinking reaction of vinyl resin and accelerate resin curing;

[0099] Step 5: Wrapping: The high-modulus GFRP reinforcement is spirally wound on the resin layer at an angle of 80-85° along the axial direction of the HFRP reinforcement to form a semi-wrapped structure, thus obtaining the wrapped reinforcement.

[0100] Step 6: The wrapped reinforcing material is heated and cured through a heating channel to obtain a high-modulus hybrid fiber-reinforced resin reinforcing bar product.

[0101] Comparative Example 1

[0102] The difference between this comparative example and Example 1 is that the volume ratio of carbon fiber to glass fiber in the hybrid fiber reinforced tendon in this comparative example is 1:1, while the rest is the same as in Example 1. The drawback is that it results in poor ductility of the hybrid fiber reinforced resin tendon.

[0103] Comparative Example 2

[0104] The difference between this comparative example and Example 1 is that the volume ratio of carbon fiber to glass fiber in the hybrid fiber reinforced tendon in this comparative example is 1:7, while the rest is the same as in Example 1. The drawback is that it results in lower stiffness of the hybrid fiber reinforced resin tendon.

[0105] Comparative Example 3

[0106] The difference between this comparative example and Example 1 is that the fiber volume fraction of the hybrid fiber reinforcing bar used as the core in this comparative example is 55%, while the rest is the same as in Example 1. The drawback is that it results in lower stiffness of the hybrid fiber reinforced resin bar.

[0107] Comparative Example 4

[0108] The difference between this comparative example and Example 1 is that the fiber volume ratio of the hybrid fiber reinforcing bar used as the core in this comparative example is 80%, while the rest is the same as in Example 1. The drawback is that it causes the hybrid fiber reinforced resin bar to become fuzzy and has poor stress performance.

[0109] Comparative Example 5

[0110] The difference between this comparative example and Example 1 is that the elastic modulus of E9 glass fiber in this comparative example is 130 GPa, while the rest are the same as in Example 1. The drawback is that it results in poor ductility of the hybrid fiber reinforced resin.

[0111] Comparative Example 6

[0112] The difference between this comparative example and Example 1 is that the elastic modulus of the M40JB-12000 high-modulus carbon fiber in this comparative example is 470 GPa, while the rest are the same as in Example 1. The drawback is that it results in poor ductility of the hybrid fiber reinforced resin tendon.

[0113] Comparative Example 7

[0114] The difference between this comparative example and Example 1 is that GFRP reinforcement was not used to wrap the resin layer in this comparative example. Everything else is the same as in Example 1. The drawback is that the mixed fiber reinforced resin reinforcement has poor compressive and tensile properties.

[0115] In summary, the present invention employs a high-modulus carbon glass fiber hybrid method, which can effectively improve the elastic modulus of fiber-reinforced composite reinforcement. Furthermore, the use of high-modulus and high-toughness resin can effectively improve the toughness of fiber-reinforced composites. At the same time, the external transverse semi-encapsulation of high-modulus GFRP can significantly improve the overall compressive strength of HFRP reinforcement, nearly doubling its compressive strength.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-modulus hybrid fiber reinforced resin rebar, characterized in that, It includes a hybrid fiber reinforcing bar as the core, a resin layer enclosing the core, and fiber-reinforced polymer bars wrapped around the resin layer; The volume ratio of carbon fiber to glass fiber in the hybrid fiber reinforcing bar that serves as the core is 1:2 to 1:

6. The elastic modulus of the glass fiber is 90-120 GPa, and the elastic modulus of the carbon fiber is 230-460 GPa. The fiber volume fraction of the hybrid fiber reinforcing rib, which serves as the core, is 60-75%. The resin layer comprises vinyl resin; The elastic modulus of the vinyl resin is above 3 GPa; The thickness of the resin layer is 2-3 mm; The winding includes helical winding; the angle of the helical winding is 80-85°. The fiber-reinforced polymer bar includes glass fiber-reinforced polymer bar; the elastic modulus of the glass fiber-reinforced polymer bar is 90-120 GPa.

2. The high-modulus hybrid fiber reinforced resin rebar according to claim 1, characterized in that, The glass fiber includes E9 glass fiber; The carbon fiber includes M40JB-12000 type high modulus carbon fiber.

3. A method for preparing high-modulus hybrid fiber reinforced resin reinforcement according to any one of claims 1 to 2, characterized in that, Includes the following steps: (a) Carbon fiber and glass fiber are drawn out in proportion, and then subjected to first impregnation and molding in sequence to obtain a hybrid fiber reinforcement as the core. (b) The hybrid fiber reinforcing bar obtained in step (a) as the core is impregnated with resin in a second time to form a resin layer. Then, the fiber-reinforced polymer bar is wound around the resin layer and cured to obtain the high-modulus hybrid fiber-reinforced resin bar.

4. The preparation method according to claim 3, characterized in that, The forming method includes extrusion molding in a mold.

5. The preparation method according to claim 3, characterized in that, The crosslinking initiator of the resin layer includes at least one of benzoyl peroxide and tert-butyl peroxide; The crosslinking initiator is a two-component composite initiator of benzoyl peroxide and tert-butyl peroxide.

6. The preparation method according to claim 3, characterized in that, The winding method includes the following steps: The hybrid fiber reinforcement is spirally wound on the resin layer along the axial direction.

7. The application of the high modulus hybrid fiber reinforced resin bar according to any one of claims 1 to 2 in concrete members.

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