Anchorage device for CFRP (carbon fiber reinforced plastic) rib concrete structure and CFRP rib crimping and anchoring construction process

Abstract

The invention discloses an anchorage device for a CFRP rib concrete structure and a CFRP rib compression joint anchoring construction technology. The anchorage device comprises the following steps that S1, the anchoring depth, spacing and dip angle of CFRP ribs and the number of anchorage devices are measured, the anchoring position is cleaned to ensure that no sundries, topsoil and accumulated water exist, drilling is conducted at an anchoring point according to the diameter of the anchorage device, and the drilling angle is accurately measured; and S2, sleeving the end part of the CFRP rib with a die-cast anchorage device, then feeding the anchorage device into a composite insulator crimping machine, firstly crimping the two ends of the anchorage device with the CFRP rib, and then crimping the areas of the four crimping grooves, so that the anchorage device is sunken to be attached to the CFRP rib, thereby completing the installation of the anchorage device. When the CFRP rib is anchored, the anchorage device is additionally arranged to guarantee cooperative stress of the CFRP rib and concrete, the toothed plate is additionally arranged in the anchoring cylinder, the toothed plate can be squeezed towards one side during compression joint, resistance of the CFRP rib and the anchoring cylinder is increased, the tensile resistance, compression resistance and shear resistance are improved, the anchoring efficiency can be improved, the anchoring length is effectively reduced, the anchoring device is suitable for beam end anchoring, the anchorage device is easy to manufacture, and the anchoring device is easy to manufacture. The construction is convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of CFRP reinforced concrete structures, and in particular to an anchoring scheme between CFRP reinforced concrete structures and concrete. Background Art

[0002] CFRP is the abbreviation of carbon fiber composite material. It is an advanced composite material with the advantages of high strength, light weight, no corrosion, and excellent fatigue resistance. In the construction of civil engineering, CFRP has a very obvious advantage in strengthening and fixing buildings. CFRP bars can solve the problem of steel corrosion in reinforced concrete structures due to their advantages of light weight, high strength, corrosion resistance, and fatigue resistance. They have been widely used in civil engineering.

[0003] CFRP reinforced concrete structure is to place CFRP bars in concrete instead of steel bars. The synergistic force between CFRP bars and concrete is the key to the performance of CFRP reinforced concrete structure. Since CFRP bars are weaker in compression and shearing than in tension, it is easy for CFRP bars and concrete to bond and slip during the force-bearing process, resulting in the inability of CFRP bars and concrete to bear force synergistically. Therefore, anchoring measures are often taken to ensure the synergistic force between CFRP bars and concrete. The traditional anchoring measures are to place a steel sleeve at the end of the CFRP bar, fix the steel sleeve and CFRP bar with high-strength grouting material, and ensure the anchoring efficiency by anchoring the steel sleeve to the concrete.

[0004] However, in order to ensure the reliability of the connection structure between the existing steel sleeve and the CFRP bar, the usual practice is to increase the length of the sleeve to improve the reliability of the connection structure between the steel sleeve and the CFRP bar. However, the beam-column node size is small, and the existing steel sleeve length is greater than 400mm. The steel sleeve with too long length cannot be anchored at the beam-column node, making it unsuitable for beam end anchoring, with low anchoring efficiency and complicated construction.

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

[0006] In view of the problems existing in the anchoring scheme between CFRP bars and concrete in the existing CFRP bar concrete structure, the present invention provides an anchor for CFRP bar concrete structure and a CFRP bar crimping anchoring construction process based on the anchor. This scheme can effectively increase the anchoring efficiency, reduce the anchoring length, and is suitable for beam end anchoring, etc. It can solve the problems in the traditional CFRP bar crimping anchoring construction process that the steel sleeve method requires a long sleeve length, is not suitable for beam end anchoring, has low anchoring efficiency, and is complicated in construction.

[0007] To achieve the above-mentioned purpose, the present invention provides an anchor for CFRP reinforced concrete structure, including an anchor tube, wherein a plurality of crimping grooves are provided on the outer surface of the anchor tube, each of which is distributed along the circumference of the anchor tube, and the plurality of crimping grooves are spaced apart along the axial direction of the anchor tube, so as to divide the outer surface of the anchor tube into a plurality of crimping control areas corresponding to the extrusion spacing of the crimping machine; a plurality of rows of grooves are provided on the outer surface of the anchor tube, and the rows of grooves are arranged along the circumference of the anchor tube, and a plurality of groups of tooth plate assemblies are provided on the inner wall of the anchor tube, and the plurality of groups of tooth plate assemblies are spaced apart along the axial direction of the anchor tube, and respectively correspond to the plurality of crimping grooves on the outer surface of the anchor tube.

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

[0009] In some embodiments of the present invention, widths of some regions in the plurality of crimping control regions are the same.

[0010] In some embodiments of the present invention, the plurality of crimping control areas are divided into section A and section B, the crimping amount of section A is 0.35-0.4 mm, the crimping amount of section B is 0.3-0.38 mm, and the length of section A and section B is determined by the length of the anchor tube.

[0011] In some embodiments of the present invention, each group of tooth plate assemblies is composed of a plurality of tooth plates that are arranged in a circular shape and at equal distances along the circumference of the inner wall of the anchor tube.

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

[0013] To achieve the above object, the CFRP bar crimping anchoring construction process provided by the present invention comprises the following steps:

[0014] Step 1: Construction preparation stage;

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

[0016] Step 2: Anchor installation;

[0017] The die-cast anchor is placed on the end of the CFRP bar, and then the anchor is sent to the composite insulator crimping machine. First, the two ends of the anchor are crimped with the CFRP bar, and then the area of ​​multiple crimping grooves is crimped to make it inward and fit with the CFRP bar, and the anchor installation is completed;

[0018] Step 3: Grouting filling;

[0019] Insert the CFRP bar with the anchor installed into the drilled installation hole, then inject cement mortar into the hole and vibrate it with a vibrating rod so that the concrete can fully fill the gap and completely wrap the anchor to form a stable anchoring section;

[0020] Step 4: Maintenance;

[0021] Water the completed areas with a watering cycle of 2-4 days to keep the construction areas moist.

[0022] In some embodiments of the present invention, the construction process requires cleaning the surface of the anchor before grouting filling, and the anchor is fully inserted into the mounting hole in a vertical state and the anchor needs to be inserted into the center position of the mounting hole; during grouting filling, the grouting is allowed to enter the interior of the groove on the surface of the anchor.

[0023] In some embodiments of the present invention, the depth of the CFRP tendon anchoring measurement stage is determined by the length of the anchoring tube, the spacing is determined by the number of CFRP tendons to be anchored, the inclination angle is determined by the anchoring angle, anchors are installed at both ends of each CFRP tendon, and the diameter of the drilled hole is +5mm of the outer diameter of the anchor.

[0024] In some embodiments of the present invention, the construction process is to send the anchor into a tensile machine for a tensile test after the anchor is crimped. For the CFRP tendons 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 the present invention has the following beneficial effects:

[0026] 1. The present invention installs the anchor by crimping. The anchor is crimped to the end of the CFRP tendon by a crimping machine. The anchor is divided into five areas during crimping. The crimping is performed in an AB segmented manner. The crimping amount is ensured to be 0.3mm-0.4mm, thereby ensuring the stability of the connection between the anchor and the CFRP tendon and preventing it from detaching easily.

[0027] 2. The present invention adds anchors when anchoring CFRP tendons to ensure that the CFRP tendons and concrete are subjected to coordinated force. Compared with traditional steel sleeves, multiple grooves are designed on the outer surface of the anchor tube to improve the coordinated force between the concrete and the anchor tube. During grouting, the concrete enters the inside of the grooves to increase the contact area. At the same time, a tooth plate is added inside the anchor tube. During crimping, the tooth plate will be squeezed to one side to increase the resistance between the CFRP tendons and the anchor tube, improve the tensile, compressive and shear resistance, increase the anchoring efficiency, and effectively reduce the anchoring length. Compared with the traditional steel sleeve with a length greater than 400mm, the crimping anchor in the present invention is less than 300mm long, which can be suitable for anchoring at smaller beam-column nodes, so that it can be suitable for beam end anchoring. The anchor is simple to make and easy to construct. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

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

[0031] Figure 3 It is a structural schematic diagram of the anchor for CFRP reinforced concrete structure in Example 2 of the present invention;

[0032] Figure 4 It is a schematic diagram of the structure of the anchor for the CFRP reinforced concrete structure in Example 3 of the present invention.

[0033] The meanings of the reference numerals in the figure are: 1-anchoring tube; 2-crimping groove; 3-groove; 4-tooth plate. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0035] Embodiment 1

[0036] In view of the structural characteristics of the coordinated cooperation between CFRP bars and concrete in CFRP bar concrete structures, this example adds anchors when anchoring CFRP bars to ensure that the CFRP bars and concrete are subjected to coordinated forces. At the same time, the anchors increase the resistance between the CFRP bars and the anchor tube based on an innovative crimping anchoring method, thereby improving the tensile, compressive and shear resistance, increasing the anchoring efficiency, and effectively reducing the anchoring length. It is suitable for beam end anchoring, and the anchors are simple to make and easy to construct.

[0037] In this example, the anchor tube in the anchor is squeezed inwards based on its own deformation, thereby forming a stable and reliable crimping anchoring structure for the internal CFRP tendons.

[0038] See also Figure 1 and Figure 2 The anchor provided in this example is specifically composed of an anchor tube 1, which is in the shape of a hollow cylinder as a whole and has two truncated cones at its two ends.

[0039] The outer surface of the anchor tube 1 is provided with a plurality of crimping grooves 2, each of which is distributed in a ring shape along the circumference of the anchor tube. Meanwhile, the plurality of crimping grooves are spaced apart along the axial direction of the anchor tube, dividing the outer surface of the anchor tube into a plurality of crimping control areas.

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

[0041] In order to avoid the influence of the groove structure of the crimping groove 2 on the overall performance of the anchor tube 1, in this example, the wall of the anchor tube 1 is integrally concave at the corresponding position to form the corresponding crimping groove 2, which does not affect the overall structure of the anchor tube 1. Figure 2 shown.

[0042] Furthermore, the crimping groove 2 here is in an inverted trapezoidal shape as a whole, which is convenient for cooperation with a crimping machine.

[0043] Furthermore, a plurality of crimping grooves 2 on the outer surface of the anchor tube 1 are spaced apart along the axial direction of the anchor tube corresponding to the extrusion spacing of the crimping machine, thereby cooperating with the crimping machine.

[0044] Furthermore, the widths of the several crimping control areas divided by the several crimping grooves 2 on the outer surface of the anchor tube 1 are not completely the same, and it is preferred that the widths of some of the several crimping control areas are the same. Specifically, the crimping amount of each crimping control area is controlled between 0.3mm-0.4mm to ensure that the widths of the three areas are the same, wherein the crimping amount should not be less than 0.3mm to ensure the anchoring effect of the CFRP tendons, and the crimping amount should not be greater than 0.4mm to prevent shear damage of the CFRP tendons during the crimping process.

[0045] As a further explanation, the several crimping control areas formed on the outer surface of the anchor tube 1 in this example have two forms: section A and section B, wherein the crimping amount of section A is 0.4 mm, and the crimping amount of section B is 0.38 mm. The lengths of sections A and B are determined by the length of the anchor tube 1. Here, the crimping amount of section B is set to be smaller than the crimping amount of section A, thereby preventing the CFRP tendons from being damaged due to stress concentration.

[0046] Based on the above scheme, in this example, several rows of grooves 3 are arranged on the outer surface of the anchor tube 1, and each row of grooves 3 extends from one end of the outer surface of the anchor tube along the axial direction of the anchor tube 1 to the other end of the outer surface of the anchor tube; at the same time, the several rows of grooves 3 are arranged in a circular shape with equal distances along the circumference of the anchor tube.

[0047] The multiple rows of grooves 3 arranged on the outer surface of the anchor tube 1 can effectively improve the coordinated force effect of the concrete and the anchor tube 1.

[0048] As a preferred arrangement, several rows of grooves 3 are arranged in a circular pattern with equal distances along the circumference of the anchor tube, one at intervals of 30°, thereby ensuring that the coordinated force state between the concrete and the anchor tube 1 is optimal.

[0049] On the basis of the above scheme, in this example, a plurality of groups of tooth plate assemblies are arranged on the inner wall of the anchor tube 1, and the plurality of groups of tooth plate assemblies are spaced apart along the axial direction of the anchor tube and correspond to a plurality of crimping grooves on the outer surface of the anchor tube respectively; at the same time, each group of tooth plate assemblies is composed of a plurality of tooth plates 4 arranged in an annular manner and at equal distances along the circumferential direction of the inner wall of the anchor tube, such as Figure 2 shown.

[0050] The several groups of tooth plate assemblies arranged in this way correspond to the several crimping grooves 2 on the outer surface of the anchor tube 1. When the anchor tube 1 is crimped at the crimping groove 2, the driving tooth plate 4 can be synchronously squeezed inward, thereby increasing the resistance between the CFRP tendons and the anchor tube 1, improving the tensile, compressive and shear resistance, increasing the anchoring efficiency, and effectively reducing the anchoring length, which is suitable for beam end anchoring.

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

[0052] When such a structured anchor is used, it is installed by crimping. The anchor is crimped to the end of the CFRP bar by a crimping machine. The anchor is divided into several areas during crimping. The crimping is performed in an AB segmented manner. 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 being easily separated. In this way, when the CFRP bar is anchored, an anchor is added to ensure that the CFRP bar and concrete are subjected to coordinated force. Compared with the traditional steel sleeve, multiple grooves 3 are designed on the outer surface of the anchor tube 1 in the anchor in this example to improve the coordinated force between the concrete and the anchor tube 1. During grouting, the concrete enters the inside of the groove 3 to increase the contact area. At the same time, a tooth plate 4 is added inside the anchor tube 1. During crimping, the tooth plate 4 will be squeezed to one side to increase the resistance between the CFRP tendon and the anchor tube 1, improve the tensile, compressive and shear resistance, increase the anchoring efficiency, effectively reduce the anchoring length, and is suitable for beam end anchoring. The anchor is simple to make and easy to construct. It solves the problem that the steel sleeve method in the traditional CFRP tendon crimping anchoring construction process requires a long sleeve length, is not suitable for beam end anchoring, has a low anchoring efficiency, and is complex to construct.

[0053] The following specifically describes the process of performing CFRP bar crimping and anchoring construction in a CFRP bar concrete structure based on the CFRP bar concrete structure anchor.

[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 and number of anchors of the CFRP bars, clean the anchorage position to ensure there is no debris, loose soil and water accumulation, drill holes at the anchorage points according to the anchor diameter, and accurately measure the drilling angles.

[0057] Step 2: Anchor installation:

[0058] The die-cast anchor is put on the end of the CFRP reinforcement, and then the anchor is sent into the composite insulator crimping machine. First, the two ends of the anchor are crimped to the CFRP reinforcement, and then the four crimping grooves are crimped to make them concave and fit the CFRP reinforcement to complete the installation of the anchor.

[0059] After the anchor crimping is completed, the CFRP reinforcement is sent into the tensile machine for tensile testing. The test shows that the anchor installation meets the first-level tensile standard.

[0060] Step 3: Grouting filling:

[0061] Insert the CFRP reinforcement with the installed anchor into the drilled mounting hole, ensure that the anchor is fully inserted, vertical and positioned accurately, use the corresponding grouting equipment to ensure that the anchor is in the center of the mounting hole, inject cement mortar into the hole, vibrate with a vibrating rod, ensure that the concrete fully fills the gap and completely wraps the anchor to form a stable anchoring section.

[0062] Step 4: Maintenance:

[0063] Water the completed construction area with a watering cycle of three days to keep the construction area moist.

[0064] As a further explanation, in step one, the depth of the CFRP tendon anchoring measurement stage is determined by the length of the anchor tube 1, the spacing is determined by the number of CFRP tendons to be anchored, the inclination is determined by the anchoring angle, and anchors are installed at both ends of each CFRP tendon. The diameter of the drilled hole is +5mm of the outer diameter of the anchor.

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

[0066] Meanwhile, the length of the anchor tube 1 formed by die casting is 150 mm, the outer diameter is 35 mm, the inner diameter is the diameter of the CFRP bar + 0.15 mm, and the crimping groove 2 divides the outer surface of the anchor tube 1 into five areas; the areas are divided into AAABB segments, where the crimping amount of the A segment area is 0.4, the crimping amount of the B segment area is 0.38, the width of the A segment area is 32 mm, and the width of the B segment area is 27 mm. Figure 1 shown.

[0067] At the same time, after the anchor is crimped, it is sent to a tensile machine for a tensile test with a tensile grade of 1. The CFRP tendons that fail the tensile test will have the anchor removed and reinstalled, and the crimping amount will be increased during the installation process.

[0068] As a further explanation, in step three, before grouting, the surface of the anchor needs to be cleaned to ensure that there is no debris on the surface. At the same time, the anchor is fully inserted into the mounting hole in a vertical state and the anchor needs to be inserted into the center of the mounting hole; when grouting, the grouting is allowed to enter the inside of the groove on the surface of the anchor.

[0069] Compared with the traditional steel sleeve bonded to the CFRP tendon through high-strength grouting material and then anchored to the concrete, the construction process has low anchoring efficiency, CFRP tendon slippage is prone to occur, and the steel sleeve is long and is not suitable for beam end anchoring.

[0070] The crimping anchoring construction process given in this example scheme can greatly reduce the anchoring length, is suitable for beam end anchoring, and the anchor and CFRP bars will not slip, with high anchoring efficiency.

[0071] At the same time, according to 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 order. Please refer to the solutions of Example 2 and Example 3 for further details.

[0072] Embodiment 2

[0073] See also Figure 3 Compared with the CFRP bar crimping anchoring construction process given in Example 1, this example adjusts Step 2 while keeping the other steps unchanged in Example 1. The adjusted contents are as follows:

[0074] The anchor is composed of an anchor tube 1, a crimping groove 2, a groove 3 and a tooth plate 4. Four crimping grooves 2 are provided on the outer surface of the anchor tube 1; a plurality of rows of grooves 3 are provided on the outer surface of the anchor tube 1, and each row of grooves 3 extends from one end of the outer surface of the anchor tube along the axial direction of the anchor tube 1 to the other end of the outer surface of the anchor tube; at the same time, the plurality of rows of grooves 3 are arranged in a circular shape with equal distances along the circumference of the anchor tube; the interior of the anchor tube 1 is provided with tooth plates 4 which are arranged in a circular shape with equal distances on the inner wall of the anchor tube 1.

[0075] The die-cast anchor is put on the end of the CFRP reinforcement, and then the anchor is sent into the composite insulator crimping machine. First, the two ends of the anchor are crimped to the CFRP reinforcement, and then the four crimping grooves are crimped to make them concave and fit the CFRP reinforcement to complete the installation of the anchor.

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

[0077] After the anchor crimping is completed, the CFRP reinforcement is sent into the tensile machine for tensile testing. The test shows that the anchor installation meets the first-level tensile standard.

[0078] In this example solution, by reducing the crimping amount of section A and section B, it is possible to reduce the damage to the CFRP tendons that may be caused during the crimping process, increase the anchoring length, and compensate for the weakening of the anchoring force caused by reducing the crimping amount. The anchoring strength is determined to be 1527MPa through a pull-out test. Compared with the anchoring strength of 1828MPa in Example 1, the anchoring strength is reduced by 16%, achieving an excellent anchoring effect.

[0079] Embodiment 3

[0080] See also Figure 4 Compared with the CFRP bar crimping anchoring construction process given in Example 1, this example adjusts Step 2 while keeping the other steps unchanged in Example 1. The adjusted contents are as follows:

[0081] The anchor is composed of an anchor tube 1, a crimping groove 2, a groove 3 and a tooth plate 4. Four crimping grooves 2 are provided on the outer surface of the anchor tube 1; a plurality of rows of grooves 3 are provided on the outer surface of the anchor tube 1, and each row of grooves 3 extends from one end of the outer surface of the anchor tube along the axial direction of the anchor tube 1 to the other end of the outer surface of the anchor tube; at the same time, the plurality of rows of grooves 3 are arranged in a circular shape with equal distances along the circumference of the anchor tube; the interior of the anchor tube 1 is provided with tooth plates 4 which are arranged in a circular shape with equal distances on the inner wall of the anchor tube 1.

[0082] The die-cast anchor is put on the end of the CFRP reinforcement, and then the anchor is sent into the composite insulator crimping machine. First, the two ends of the anchor are crimped to the CFRP reinforcement, and then the four crimping grooves are crimped to make them concave and fit the CFRP reinforcement to complete the installation of the anchor.

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

[0084] After the anchor crimping is completed, the CFRP reinforcement is sent into the tensile machine for tensile testing. The test shows that the anchor installation meets the first-level tensile standard.

[0085] In this example, the crimping amount of section A and section B is reduced, thereby reducing the damage that may be caused to the CFRP tendons during the crimping process, increasing the anchoring length, and compensating for the weakening of the anchoring force caused by reducing the crimping amount. The anchoring strength is determined to be 1635MPa through a pull-out test, which is 11% less than the anchoring strength of 1828MPa in Example 1, achieving an excellent anchoring effect.

[0086] Through the above cases, it can be concluded that different anchoring effects can be achieved by adjusting the anchor length, outer diameter, crimping amount, crimping area length and arrangement order to meet different application scenarios. During the anchor installation stage, the anchor using this process solution is installed through the crimping process, which can effectively ensure the stability of the installation. The tensile test can be used to improve the tensile, compressive and shear resistance of the CFRP bars after anchoring, which can increase the anchoring efficiency and effectively reduce the anchoring length. It is suitable for beam end anchoring, and the anchor is simple to make and easy to construct.

[0087] In summary, the solution provided in the example of the present invention is to install the anchor by crimping. The anchor is crimped to the end of the CFRP tendon by a crimping machine. During crimping, the anchor is divided into five areas and crimped in an AB segmented manner. The crimping amount is ensured to be 0.3mm-0.4mm, which ensures the stability of the connection between the anchor and the CFRP tendon and prevents it from detaching easily. When anchoring the CFRP tendons, anchors are added to ensure that the CFRP tendons and concrete are subjected to coordinated force. Compared with traditional steel sleeves, multiple grooves 3 are designed on the outer surface of the anchor tube 1 to improve the coordinated force between the concrete and the anchor tube 1. During grouting, the concrete enters the inside of the grooves 3 to increase the contact area. At the same time, a tooth plate 4 is added to the inside of the anchor tube 1. During crimping, the tooth plate 4 will be squeezed to one side to increase the resistance between the CFRP tendons and the anchor tube 1, improve the tensile, compressive and shear resistance, increase the anchoring efficiency, effectively reduce the anchoring length, and be suitable for beam end anchoring. The anchor is simple to make and easy to construct, which solves the problem that the steel sleeve method in the traditional CFRP tendon crimping anchoring construction process requires a long sleeve length, is not suitable for beam end anchoring, has a low anchoring efficiency, and is complex to construct.

[0088] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An anchor for a CFRP reinforced concrete structure, comprising an anchoring tube, characterized in that: The outer surface of the anchor tube is provided with a plurality of crimping grooves, each of which is distributed along the circumference of the anchor tube, and the plurality of crimping grooves are spaced apart along the axial direction of the anchor tube, so as to divide the outer surface of the anchor tube into a plurality of crimping control areas corresponding to the extrusion spacing of the crimping machine; the outer surface of the anchor tube is provided with a plurality of rows of grooves, and the rows of grooves are arranged along the circumference of the anchor tube, and the inner wall of the anchor tube is provided with a plurality of groups of tooth plate assemblies, and the plurality of groups of tooth plate assemblies are spaced apart along the axial direction of the anchor tube, and respectively correspond to the plurality of crimping grooves on the outer surface of the anchor tube.

2. The CFRP reinforced concrete structure anchor according to claim 1, characterized in that: The length of the anchor tube is 50mm-300mm, the outer diameter is 30mm-35mm, and the inner diameter is +0.1mm-0.15mm of the CFRP bar diameter.

3. The CFRP reinforced concrete structure anchor according to claim 1, characterized in that: The widths of some areas in the plurality of crimping control areas are the same.

4. The CFRP reinforced concrete structure anchor according to claim 3, characterized in that: The plurality of crimping control areas are divided into the form of section A and section B. The crimping amount of section A is 0.35-0.4 mm, and the crimping amount of section B is 0.3-0.38 mm. The lengths of section A and section B are determined by the length of the anchor tube.

5. The CFRP reinforced concrete structure anchor according to claim 1, characterized in that: Each group of tooth plate assemblies is composed of a plurality of tooth plates which are arranged in a circular shape and at equal distances along the circumference of the inner wall of the anchoring tube.

6. The CFRP reinforced concrete structure anchor according to claim 1, characterized in that: The plurality of rows of grooves are arranged equidistantly at intervals of 30° along the circumference of the anchoring tube.

7. A CFRP bar crimping anchoring construction process, characterized in that: The steps include: Step 1: Construction preparation stage; Measure the anchorage depth, spacing, inclination and number of anchors of CFRP bars, clean the anchorage position, drill holes at the anchorage points according to the anchor diameter, and accurately measure the drilling angles; Step 2: Anchor installation; The die-cast anchor is placed on the end of the CFRP bar, and then the anchor is sent to the composite insulator crimping machine. First, the two ends of the anchor are crimped with the CFRP bar, and then the area of ​​multiple crimping grooves is crimped to make it inward and fit with the CFRP bar, and the anchor installation is completed; Step 3: Grouting filling; Insert the CFRP bar with the anchor installed into the drilled installation hole, then inject cement mortar into the hole and vibrate it with a vibrating rod so that the concrete can fully fill the gap and completely wrap the anchor to form a stable anchoring section; Step 4: Maintenance; Water the completed areas with a watering cycle of 2-4 days to keep the construction areas moist.

8. The CFRP bar crimping and anchoring construction process according to claim 7, characterized in that: The construction process requires cleaning the surface of the anchor before grouting, and the anchor is fully inserted into the mounting hole in a vertical state and the anchor needs to be inserted into the center of the mounting hole; during grouting, the grouting is allowed to enter the interior of the groove on the surface of the anchor.

9. The CFRP bar crimping and anchoring construction process according to claim 7, characterized in that: The depth of the CFRP tendon anchoring measurement stage is determined by the length of the anchoring tube, the spacing is determined by the number of CFRP tendons to be anchored, and the inclination is determined by the anchoring angle. Anchors are set at both ends of each CFRP tendon, and the diameter of the drilled hole is +5mm of the outer diameter of the anchor.

10. The CFRP bar crimping anchoring construction process according to claim 7, characterized in that: The construction process is to send the anchor into a tensile machine for a tensile test after the anchor is crimped. For the CFRP bars that fail the tensile test, the anchor is removed and reinstalled, and the crimping amount is increased during the installation process.

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