Anchor for CFRP reinforced concrete structure and CFRP reinforced concrete structure anchoring construction process

Abstract

This invention discloses an anchorage for CFRP (Cemented Reinforced Polymer) reinforced concrete structures and a CFRP reinforcement crimping and anchoring construction process, including the following steps: S1, measuring the CFRP reinforcement anchorage depth, spacing, inclination angle, and number of anchorages; cleaning the anchorage location to ensure there is no debris, loose soil, or standing water; drilling holes at the anchorage points according to the anchorage diameter, and accurately measuring the drilling angle; S2, fitting the die-cast anchorage onto the end of the CFRP reinforcement, and then feeding the anchorage into a composite insulator crimping machine. First, crimp the two ends of the anchorage to the CFRP reinforcement, then crimp the four crimping groove areas to make them recessed and fit snugly against the CFRP reinforcement, completing the anchorage installation. This invention adds anchorages during CFRP reinforcement anchorage to ensure that the CFRP reinforcement and concrete share the load. A toothed plate is added inside the anchorage cylinder; during crimping, the toothed plate will be squeezed to one side, increasing the resistance between the CFRP reinforcement and the anchorage cylinder, improving tensile, compressive, and shear resistance, increasing anchorage efficiency, effectively reducing anchorage length, and is suitable for beam end anchorage. The anchorage is simple to manufacture and easy to construct.

Description

Technical Field

[0001] This invention relates to the field of CFRP reinforced concrete structure technology, specifically to the anchorage scheme between CFRP reinforcement and concrete in CFRP reinforced concrete structures. Background Technology

[0002] CFRP (Carbon Dioxide Reinforced Polymer) is an advanced composite material with advantages such as high strength, light weight, non-corrosion properties, and excellent fatigue resistance. In civil engineering construction, CFRP materials offer significant advantages in strengthening and fixing structures. Due to its lightweight, high strength, corrosion resistance, and fatigue resistance, CFRP bars can solve the problem of steel corrosion in reinforced concrete structures and are widely used in civil engineering.

[0003] CFRP-reinforced concrete structures utilize CFRP bars instead of steel reinforcement within concrete. The key to maximizing the structural performance of CFRP-reinforced concrete structures lies in the coordinated stress distribution between the CFRP bars and the concrete. However, due to the relatively weak compressive and shear strength of CFRP bars compared to their tensile strength, bond slippage between the CFRP bars and concrete is prone to occur during stress loading, preventing them from working together effectively. Therefore, anchoring measures are often employed to ensure this coordinated stress distribution. Traditional anchoring methods involve placing steel sleeves at the ends of the CFRP bars, securing them to the bars with high-strength grout, and ensuring anchoring efficiency through the anchorage between the steel sleeves and the concrete.

[0004] However, to ensure the reliability of the connection between the existing steel sleeve and the CFRP reinforcement, the common practice is to increase the length of the sleeve. However, the beam-column joint is relatively small, and the existing steel sleeves are longer than 400mm. These excessively long sleeves cannot be anchored at the beam-column joint, making them unsuitable for beam end anchoring, resulting in low anchoring efficiency and complex construction.

[0005] Therefore, how to effectively reduce the anchorage length between CFRP bars and concrete in CFRP-reinforced concrete structures and improve anchorage efficiency to make them suitable for beam end anchorage is an urgent problem to be solved in this field. Summary of the Invention

[0006] To address the problems existing in current anchorage schemes between CFRP bars and concrete in CFRP-reinforced concrete structures, this invention provides an anchorage for CFRP-reinforced concrete structures and a CFRP bar press-fit anchorage construction process based on this anchorage. This solution can effectively increase anchorage efficiency, reduce anchorage length, and is suitable for beam end anchorage, etc. It can solve the problems of traditional CFRP bar press-fit anchorage construction processes, such as the requirement for long sleeve lengths, unsuitability for beam end anchorage, low anchorage efficiency, and complex construction.

[0007] To achieve the above objectives, the present invention provides an anchor for CFRP reinforced concrete structures, comprising an anchor cylinder. The outer surface of the anchor cylinder is provided with a plurality of crimping grooves, each crimping groove being distributed circumferentially along the anchor cylinder. The plurality of crimping grooves are spaced apart axially along the anchor cylinder, dividing the outer surface of the anchor cylinder into a plurality of crimping control areas corresponding to the crimping spacing of a crimping machine. The outer surface of the anchor cylinder is provided with a plurality of rows of grooves, which are arranged circumferentially along the anchor cylinder. The inner wall of the anchor cylinder is provided with a plurality of sets of toothed plate assemblies, which are spaced apart axially along the anchor cylinder and respectively correspond to the plurality of crimping grooves on the outer surface of the anchor cylinder.

[0008] In some embodiments of the present invention, the length of the anchoring cylinder is 50mm-300mm, the outer diameter is 30mm-35mm, and the inner diameter is +0.1mm-0.15mm of the diameter of the CFRP bar.

[0009] In some embodiments of the present invention, some regions of the plurality of crimping control regions have the same width.

[0010] In some embodiments of the present invention, the plurality of crimping control areas are divided into sections A and B, with the crimping amount of section A being 0.35-0.4 mm and the crimping amount of section B being 0.3-0.38 mm. The lengths of sections A and B are determined by the length of the anchoring cylinder.

[0011] In some embodiments of the present invention, each set of toothed plate assemblies consists of a plurality of toothed plates arranged in a ring at equal intervals along the circumferential direction of the inner wall of the anchoring cylinder.

[0012] In some embodiments of the present invention, the grooves are arranged in a plurality of rows at equal intervals of 30° along the circumference of the anchoring cylinder.

[0013] To achieve the above objectives, the CFRP bar press-fit anchorage construction process provided by the present invention includes the following steps:

[0014] Step 1: Construction Preparation Stage;

[0015] Measure the anchorage depth, spacing, inclination angle, and number of anchors for CFRP bars; clean the anchorage location; drill holes at the anchorage points according to the anchor diameter; and accurately measure the drilling angle.

[0016] Step 2: Anchor installation;

[0017] The die-cast anchor is fitted onto the end of the CFRP bar, and then the anchor is fed into the composite insulator crimping machine. First, the two ends of the anchor are crimped with the CFRP bar, and then the area with multiple crimping grooves is crimped to make it recessed and fit with the CFRP bar, thus completing the anchor installation.

[0018] Step 3: Grouting and filling;

[0019] Insert the CFRP bar with the anchor installed into the drilled installation hole, then inject cement mortar into the hole, and use a vibrator to vibrate it so that the concrete fully fills the gap and completely wraps the anchor, forming a stable anchoring section.

[0020] Step 4: Maintenance;

[0021] Water the completed areas every 2-4 days to keep them moist.

[0022] In some embodiments of the present invention, the construction process requires cleaning the surface of the anchor before grouting, and the anchor is fully inserted into the installation hole in a vertical state with the anchor inserted into the center of the installation hole; during grouting, the grout enters the interior of the groove on the surface of the anchor.

[0023] In some embodiments of the present invention, the depth of the CFRP bar anchorage measurement stage is determined by the length of the anchorage cylinder, the spacing is determined by the number of CFRP bars to be anchored, the inclination angle is determined by the anchorage angle, and anchorages are fitted at both ends of each CFRP bar, with the diameter of the drilled hole being +5mm of the outer diameter of the anchorage.

[0024] In some embodiments of the present invention, the construction process involves sending the anchor crimped into a tensile test machine after the anchor crimping is completed. For CFRP bars that fail the tensile test, the anchor is removed and reinstalled, and the crimping amount is increased during the installation process.

[0025] Compared with the prior art, the technical solution provided by this invention has the following advantages:

[0026] 1. This invention installs the anchor by crimping. The anchor is crimped to the end of the CFRP bar using a crimping machine. During crimping, the anchor is divided into five areas and crimped in sections AB. The crimping amount is ensured to be 0.3mm-0.4mm, which ensures the stability of the connection between the anchor and the CFRP bar and prevents it from easily detaching.

[0027] 2. This invention adds an anchor to the CFRP reinforcement to ensure that the CFRP reinforcement and concrete share the load. Compared with the traditional steel sleeve, the outer surface of the anchor cylinder is designed with multiple grooves to enhance the synergistic force sharing between the concrete and the anchor cylinder. During grouting, the concrete enters the interior of the grooves, increasing the contact area. At the same time, a toothed plate is added inside the anchor cylinder. During compression, the toothed plate will be squeezed to one side, increasing the resistance between the CFRP reinforcement and the anchor cylinder, improving tensile, compressive and shear resistance, increasing anchoring efficiency and effectively reducing the anchoring length. Compared with the traditional steel sleeve with a length greater than 400mm, the compression anchor in this invention is less than 300mm long, which is suitable for anchoring at beam-column joints with smaller dimensions, thus making it suitable for beam end anchoring. The anchor is simple to manufacture and easy to construct. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0029] Figure 1 This is a schematic diagram of the anchorage used in the CFRP reinforced concrete structure in Example 1 of the present invention;

[0030] Figure 2 This is a schematic diagram of the internal structure of the anchorage for CFRP reinforced concrete structure in Example 1 of the present invention;

[0031] Figure 3 This is a schematic diagram of the anchorage used in the CFRP reinforced concrete structure in Example 2 of the present invention;

[0032] Figure 4 This is a schematic diagram of the anchorage used in the CFRP reinforced concrete structure in Example 3 of the present invention.

[0033] The meanings of the labels in the attached diagram are as follows: 1-Anchor cylinder; 2-Crimping groove; 3-Groove; 4-Toothed plate. Detailed Implementation

[0034] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0035] Example 1

[0036] In response to the structural characteristics of the synergistic cooperation between CFRP reinforcement and concrete in CFRP reinforced concrete structures, this example adds anchorages during CFRP reinforcement anchoring to ensure that the CFRP reinforcement and concrete share the load. At the same time, the anchorages are based on an innovative press-fit anchoring method to increase the resistance between the CFRP reinforcement and the anchorage cylinder, thereby improving tensile, compressive and shear resistance, increasing anchorage efficiency, effectively reducing anchorage length, and making it suitable for beam end anchorage. The anchorages are simple to manufacture and easy to construct.

[0037] In this example, the anchoring cylinder in the anchorage compresses inward based on its own deformation, thereby forming a stable and reliable press-fit anchoring structure for the internal CFRP reinforcement.

[0038] See Figure 1 and Figure 2 The anchor given in this example is specifically composed of an anchoring cylinder 1, which is a hollow cylindrical shape with frustum-shaped ends.

[0039] The outer surface of the anchor cylinder 1 is provided with several crimping grooves 2. Each crimping groove is distributed in a ring along the circumference of the anchor cylinder, and the several crimping grooves are spaced apart along the axial direction of the anchor cylinder, dividing the outer surface of the anchor cylinder into several crimping control areas.

[0040] The crimping groove 2 here is used to define the crimping part on the anchoring cylinder 1 that cooperates with the crimping machine. The area where the crimping groove 2 is located can cooperate with the crimping machine to generate deformation inward synchronously and then press and fix the CFRP bar located in the anchoring cylinder 1, thereby forming a crimp.

[0041] To avoid the impact of the groove structure of the crimping groove 2 on the overall performance of the anchoring cylinder 1, in this example, the corresponding crimping groove 2 is formed by an integral inward concavity in the corresponding part of the anchoring cylinder 1 wall. This does not affect the overall structural formation of the anchoring cylinder 1. Figure 2 As shown.

[0042] Furthermore, the crimping groove 2 here is generally inverted trapezoidal in shape, which facilitates its use with the crimping machine.

[0043] Furthermore, the several crimping grooves 2 on the outer surface of the anchor cylinder 1 are distributed at intervals along the axial direction of the anchor cylinder, corresponding to the crimping distance of the crimping machine, thereby cooperating with the crimping machine.

[0044] Furthermore, the widths of the several crimping control areas divided by the crimping grooves 2 on the outer surface of the anchoring cylinder 1 are not entirely the same. Preferably, some areas of the several crimping control areas have the same width. Specifically, the crimping amount of each crimping control area is controlled between 0.3mm and 0.4mm to ensure that the widths of the three areas are the same. The crimping amount should not be less than 0.3mm to ensure the anchoring effect of the CFRP reinforcement, and the crimping amount should not be greater than 0.4mm to prevent shearing damage to the CFRP reinforcement during the crimping process.

[0045] As further explanation, the several crimping control areas formed on the outer surface of the anchor cylinder 1 in this example have two forms: segment A and segment B. The crimping amount of segment A is 0.4 mm, and the crimping amount of segment B is 0.38 mm. The lengths of segments A and B are determined by the length of the anchor cylinder 1. Here, the crimping amount of segment B is set to be less than that of segment A, thereby preventing stress concentration and damage to the CFRP reinforcement.

[0046] Based on the above scheme, this example provides several rows of grooves 3 on the outer surface of the anchoring cylinder 1. Each row of grooves 3 extends from one end of the outer surface of the anchoring cylinder along the axial direction of the anchoring cylinder 1 to the other end of the outer surface of the anchoring cylinder. At the same time, the several rows of grooves 3 are arranged in a ring at equal intervals along the circumference of the anchoring cylinder.

[0047] The multiple rows of grooves 3 arranged on the outer surface of the anchor cylinder 1 can effectively improve the synergistic force-bearing effect between the concrete and the anchor cylinder 1.

[0048] As a preferred arrangement, several rows of grooves 3 are arranged in a ring at equal intervals along the circumference of the anchor cylinder, with one groove every 30°, thereby ensuring that the synergistic stress state between the concrete and the anchor cylinder 1 is optimal.

[0049] Based on the above scheme, this example provides several sets of toothed plate assemblies on the inner wall of the anchoring cylinder 1. These sets of toothed plate assemblies are spaced apart along the axial direction of the anchoring cylinder and correspond to several crimping grooves on the outer surface of the anchoring cylinder. Each set of toothed plate assemblies consists of several toothed plates 4 arranged in a ring at equal intervals along the circumference of the inner wall of the anchoring cylinder, such as... Figure 2 As shown.

[0050] The toothed plate assemblies configured in this way correspond to the crimping grooves 2 on the outer surface of the anchoring cylinder 1. When the anchoring cylinder 1 is crimped at the crimping grooves 2, the driving toothed plate 4 is simultaneously squeezed inward, thereby increasing the resistance between the CFRP reinforcement and the anchoring cylinder 1, improving tensile, compressive and shear resistance, increasing anchoring efficiency, effectively reducing anchoring length, and is suitable for beam end anchoring.

[0051] In the specific implementation of the anchor formed in this example, the anchor cylinder 1 is made of 630 tempered stainless steel die casting. The length of the anchor cylinder 1 is preferably 150mm, the outer diameter is preferably 35mm, and the inner diameter is preferably +0.15mm of the diameter of the CFRP bar.

[0052] When using anchors with this structure, they are installed via crimping. A crimping machine is used to crimp the anchors to the ends of the CFRP bars. During crimping, the anchors are divided into several sections, using an AB segmentation method. The crimping depth is ensured to be between 0.3mm and 0.4mm, guaranteeing the stability of the connection between the anchor and the CFRP bar and preventing detachment. This method of adding anchors during CFRP bar anchoring ensures that the CFRP bar and concrete work together to bear the load. Compared to traditional steel sleeves, the anchoring cylinder 1 in this example has multiple grooves 3 on its outer surface to enhance the synergistic force distribution between the concrete and the anchoring cylinder 1. During grouting, the concrete is injected into the grooves 3, increasing the contact area. Simultaneously, toothed plates 4 are added inside the anchoring cylinder 1. During compression, the toothed plates 4 will be squeezed to one side, increasing the resistance between the CFRP reinforcement and the anchoring cylinder 1, thus improving tensile, compressive, and shear resistance. This increases anchoring efficiency, effectively reduces anchoring length, and is suitable for beam end anchoring. The anchoring device is simple to manufacture and easy to construct, solving the problems of traditional CFRP reinforcement compression anchoring construction processes that require long sleeve lengths, are unsuitable for beam end anchoring, have low anchoring efficiency, and are complex to construct.

[0053] The following details the process of using anchorages for CFRP-reinforced concrete structures to perform CFRP rebar compression anchorage construction.

[0054] Combination Figure 1 and Figure 2 The entire construction process includes the following steps:

[0055] Step 1: Construction Preparation Stage

[0056] Measure the anchorage depth, spacing, inclination angle, and number of anchors for CFRP bars. Clean the anchorage location to ensure there is no debris, loose soil, or standing water. Drill holes at the anchorage points according to the anchor diameter and accurately measure the drilling angle.

[0057] Step 2: Anchor Installation

[0058] The die-cast anchor is fitted onto the end of the CFRP bar, and then the anchor is fed into the composite insulator crimping machine. First, the two ends of the anchor are crimped to the CFRP bar, and then the areas of the four crimping grooves are crimped to make them recessed and fit into the CFRP bar, thus completing the anchor installation.

[0059] After the anchor crimping is completed, the CFRP bar is sent into the tensile testing machine for tensile testing. The test results show that the anchor installation meets the Class I tensile standard.

[0060] Step 3: Grouting and filling:

[0061] Insert the CFRP bar with the anchor installed into the drilled installation hole, ensuring that the anchor is fully inserted, vertical and accurately positioned. Use appropriate grouting equipment to ensure that the anchor is centered in the installation hole, inject cement mortar into the hole, and vibrate with a vibrator to ensure that the concrete fully fills the gaps and completely wraps the anchor, forming a stable anchoring section.

[0062] Step 4, Maintenance:

[0063] Water the completed areas every three days to keep them moist.

[0064] As further explained, in step one, the depth of the CFRP bar anchorage measurement stage is determined by the length of the anchorage cylinder 1, the spacing is determined by the number of CFRP bars to be anchored, the inclination angle is determined by the anchorage angle, and anchorages are fitted at both ends of each CFRP bar, with the diameter of the drilled hole being +5mm of the outer diameter of the anchorage.

[0065] As further explanation, in step two, 630 modulated stainless steel is used for die casting of the anchor. During the die casting process, different sizes of die casting molds are designed according to the requirements. The 630 modulated stainless steel solution is poured into the mold, the mold is squeezed, and after cooling, it is demolded and deburred.

[0066] Meanwhile, the die-cast anchor cylinder 1 has a length of 150mm, an outer diameter of 35mm, and an inner diameter of +0.15mm (the diameter of the CFRP reinforcement). The crimping groove 2 divides the outer surface of the anchor cylinder 1 into five regions; these regions are in the form of AAABB segments, where the crimping amount for segment A is 0.4, the crimping amount for segment B is 0.38, the width of segment A is 32mm, and the width of segment B is 27mm. Figure 1 As shown.

[0067] Meanwhile, after the anchor crimping is completed, it is sent to a tensile test machine for tensile testing. The tensile grade is 1. CFRP bars that fail the tensile test will have their anchors removed and reinstalled, with increased crimping during the installation process.

[0068] As further explanation, in step three, before grouting, the surface of the anchor needs to be cleaned to ensure that there are no debris on the surface. At the same time, the anchor is fully inserted into the installation hole in a vertical position and the anchor needs to be inserted into the center of the installation hole. During grouting, the grout enters the inside of the groove on the surface of the anchor.

[0069] Compared to the traditional method of bonding CFRP reinforcement with high-strength grout and then anchoring the steel sleeve to the concrete, which has the disadvantages of low anchoring efficiency, easy slippage of CFRP reinforcement, and long steel sleeve length, it is not suitable for beam end anchoring problems.

[0070] The compression anchoring construction process presented in this example greatly reduces the anchoring length, is suitable for beam end anchoring, and ensures that the anchor and CFRP reinforcement will not slip, resulting in high anchoring efficiency.

[0071] Meanwhile, depending on the required anchoring effect in the actual application scenario, different anchoring effects can be achieved by adjusting the anchor length, outer diameter, crimping amount, crimping area length and arrangement sequence. Please refer to the solutions in Embodiments 2 and 3 for further details.

[0072] Example 2

[0073] Please see Figure 3 In this example, compared to the CFRP bar press-fit anchorage construction process given in Example 1, step 2 is adjusted while keeping all other steps unchanged. The adjusted steps are as follows:

[0074] The anchor consists of an anchor cylinder 1, a crimping groove 2, a groove 3, and a toothed plate 4. The outer surface of the anchor cylinder 1 has four crimping grooves 2. The outer surface of the anchor cylinder 1 is provided with several rows of grooves 3. Each row of grooves 3 extends from one end of the outer surface of the anchor cylinder along the axial direction of the anchor cylinder 1 to the other end of the outer surface of the anchor cylinder. At the same time, the several rows of grooves 3 are arranged in a ring at equal intervals along the circumference of the anchor cylinder. The inside of the anchor cylinder 1 is provided with toothed plates 4 arranged in a ring at equal intervals on the inner wall of the anchor cylinder 1.

[0075] The die-cast anchor is fitted onto the end of the CFRP bar, and then the anchor is fed into the composite insulator crimping machine. First, the two ends of the anchor are crimped to the CFRP bar, and then the areas of the four crimping grooves are crimped to make them recessed and fit into the CFRP bar, thus completing the anchor installation.

[0076] Anchor cylinder 1 is made of 630 tempered stainless steel die casting. The length of anchor cylinder 1 is 180mm, the outer diameter is 32mm, and the inner diameter is the diameter of CFRP reinforcement + 0.12mm. The crimping groove 2 divides the outer surface of anchor cylinder 1 into five regions. The regions are divided into AABBB segments, where the crimping amount of segment A is 0.35, the crimping amount of segment B is 0.32, the width of segment A is 34mm, and the width of segment B is 37.3mm.

[0077] After the anchor crimping is completed, the CFRP bar is sent into the tensile testing machine for tensile testing. The test results show that the anchor installation meets the Class I tensile standard.

[0078] In this example, by reducing the amount of crimping in sections A and B, the damage to the CFRP reinforcement during the crimping process can be reduced, the anchorage length can be increased, and the weakening of the anchorage force caused by the reduction of the amount of crimping can be compensated. The anchorage strength was determined to be 1527 MPa through pull-out test. Compared with the anchorage strength of 1828 MPa in Example 1, the anchorage strength was reduced by 16%, achieving an excellent anchorage effect.

[0079] Example 3

[0080] Please see Figure 4 In this example, compared to the CFRP bar press-fit anchorage construction process given in Example 1, step 2 is adjusted while keeping all other steps unchanged. The adjusted steps are as follows:

[0081] The anchor consists of an anchor cylinder 1, a crimping groove 2, a groove 3, and a toothed plate 4. The outer surface of the anchor cylinder 1 has four crimping grooves 2. The outer surface of the anchor cylinder 1 is provided with several rows of grooves 3. Each row of grooves 3 extends from one end of the outer surface of the anchor cylinder along the axial direction of the anchor cylinder 1 to the other end of the outer surface of the anchor cylinder. At the same time, the several rows of grooves 3 are arranged in a ring at equal intervals along the circumference of the anchor cylinder. The inside of the anchor cylinder 1 is provided with toothed plates 4 arranged in a ring at equal intervals on the inner wall of the anchor cylinder 1.

[0082] The die-cast anchor is fitted onto the end of the CFRP bar, and then the anchor is fed into the composite insulator crimping machine. First, the two ends of the anchor are crimped to the CFRP bar, and then the areas of the four crimping grooves are crimped to make them recessed and fit into the CFRP bar, thus completing the anchor installation.

[0083] Anchor cylinder 1 is made of 630 tempered stainless steel die casting. The length of anchor cylinder 1 is 220mm, the outer diameter is 30mm, and the inner diameter is +0.1mm of the CFRP bar diameter. The crimping groove 2 divides the outer surface of anchor cylinder 1 into five regions. The regions are divided into ABABA segments, where the crimping amount of segment A is 0.36, the crimping amount of segment B is 0.34, the width of segment A is 46mm, and the width of segment B is 41mm.

[0084] After the anchor crimping is completed, the CFRP bar is sent into the tensile testing machine for tensile testing. The test results show that the anchor installation meets the Class I tensile standard.

[0085] In this example, by reducing the amount of crimping in sections A and B, the damage that may be caused to the CFRP reinforcement during the crimping process was reduced, the anchorage length was increased, and the weakening of the anchorage force caused by the reduction of the amount of crimping was compensated. The anchorage strength was determined to be 1635 MPa through pull-out test. Compared with the anchorage strength of 1828 MPa in Example 1, the anchorage strength was reduced by 11%, achieving an excellent anchorage effect.

[0086] As demonstrated by the above examples, adjusting the anchor length, outer diameter, crimping amount, crimping area length, and arrangement sequence can achieve different anchoring effects to meet various application scenarios. When anchors using this process are installed through crimping during the anchor installation phase, the stability of the installation can be effectively guaranteed. Tensile tests can be conducted to improve the tensile, compressive, and shear resistance of the CFRP reinforcement after anchoring, thereby increasing anchoring efficiency, effectively reducing anchoring length, and making it suitable for beam end anchoring. The anchors are simple to manufacture and easy to construct.

[0087] In summary, the solution provided by this invention installs the anchor by crimping. The anchor is crimped onto the end of the CFRP bar using a crimping machine. During crimping, the anchor is divided into five areas and crimped in sections AB. The crimping amount is ensured to be between 0.3mm and 0.4mm, which guarantees the stability of the connection between the anchor and the CFRP bar and prevents it from easily detaching. Anchorages are added during CFRP bar anchoring to ensure that the CFRP bar and concrete share the load. Compared with the traditional steel sleeve, the outer surface of the anchoring cylinder 1 is designed with multiple grooves 3 to enhance the shared load between the concrete and the anchoring cylinder 1. During grouting, the concrete is injected into the interior of the grooves 3 to increase the contact area. At the same time, toothed plates 4 are added inside the anchoring cylinder 1. During pressing, the toothed plates 4 will be squeezed to one side to increase the resistance between the CFRP bar and the anchoring cylinder 1, thereby improving the tensile, compressive and shear resistance, increasing the anchoring efficiency, effectively reducing the anchoring length, and making it suitable for beam end anchoring. The anchorages are simple to manufacture and easy to construct. This solves the problems of the traditional CFRP bar pressing and anchoring construction process, which requires a long sleeve length, is not suitable for beam end anchoring, has low anchoring efficiency, and is complex to construct.

[0088] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An anchorage for CFRP-reinforced concrete structures, comprising an anchoring cylinder, characterized in that, The outer surface of the anchor cylinder is provided with several crimping grooves, each crimping groove is distributed circumferentially along the anchor cylinder, and the several crimping grooves are spaced apart along the axial direction of the anchor cylinder, dividing the outer surface of the anchor cylinder into several crimping control areas corresponding to the crimping spacing of the crimping machine; the outer surface of the anchor cylinder is provided with several rows of grooves, the several rows of grooves are arranged circumferentially along the anchor cylinder, and the inner wall of the anchor cylinder is provided with several sets of toothed plate assemblies, the several sets of toothed plate assemblies are spaced apart along the axial direction of the anchor cylinder, and each corresponds to several crimping grooves on the outer surface of the anchor cylinder; the several crimping control areas are divided into sections A and B, the crimping amount of section A is 0.35-0.4mm, the crimping amount of section B is 0.3-0.38mm, and the length of section A and section B is determined by the length of the anchor cylinder.

2. The anchorage for CFRP-reinforced concrete structures according to claim 1, characterized in that, The anchoring cylinder has a length of 50mm-300mm, an outer diameter of 30mm-35mm, and an inner diameter of +0.1mm-0.15mm of the CFRP bar diameter.

3. The anchorage for CFRP-reinforced concrete structures according to claim 1, characterized in that, Some areas in the several crimping control areas have the same width.

4. The anchorage for CFRP-reinforced concrete structures according to claim 1, characterized in that, Each set of toothed plate assemblies consists of several toothed plates arranged in a ring at equal intervals along the circumference of the inner wall of the anchoring cylinder.

5. The anchorage for CFRP-reinforced concrete structures according to claim 1, characterized in that, The grooves are arranged in several rows at equal intervals of 30° along the circumference of the anchor cylinder.

6. A CFRP bar press-fit anchorage construction process, characterized in that, The construction process for anchorages used in CFRP reinforced concrete structures according to any one of claims 1-5 includes the following steps: Step 1: Construction Preparation Stage; Measure the anchorage depth, spacing, inclination angle, and number of anchors for CFRP bars; clean the anchorage location; drill holes at the anchorage points according to the anchor diameter; and accurately measure the drilling angle. Step 2: Anchor installation; The die-cast anchor is fitted onto the end of the CFRP bar, and then the anchor is fed into the composite insulator crimping machine. First, the two ends of the anchor are crimped with the CFRP bar, and then the area with multiple crimping grooves is crimped to make it recessed and fit with the CFRP bar, thus completing the anchor installation. Step 3: Grouting and filling; Insert the CFRP bar with the anchor installed into the drilled installation hole, then inject cement mortar into the hole, and use a vibrator to vibrate it so that the concrete fully fills the gap and completely wraps the anchor, forming a stable anchoring section. Step 4: Maintenance; Water the completed areas every 2-4 days to keep them moist.

7. The CFRP bar press-fit anchorage construction process according to claim 6, characterized in that, Before grouting, the surface of the anchor needs to be cleaned, and the anchor needs to be fully inserted into the installation hole in a vertical position with the anchor inserted into the center of the installation hole. During grouting, the grout enters the interior of the groove on the surface of the anchor.

8. The CFRP rebar press-fit anchorage construction process according to claim 6, characterized in that, The depth of the CFRP bar anchorage measurement stage is determined by the length of the anchorage cylinder, the spacing is determined by the number of CFRP bars to be anchored, the inclination angle is determined by the anchorage angle, and anchorages are fitted at both ends of each CFRP bar. The diameter of the drilled hole is +5mm of the outer diameter of the anchorage.

9. The CFRP bar press-fit anchorage construction process according to claim 6, characterized in that, The construction process involves sending the anchor crimped bar into a tensile testing machine after the anchor crimping is completed. For CFRP bars that fail the tensile test, the anchors are removed and reinstalled, with increased crimping during the installation process.

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