A self-locking anchoring system for FRP strips and reinforced concrete beams and its construction method

Abstract

The invention relates to the technical field of concrete structure reinforcement, and discloses a self-locking anchoring system of FRP strips and reinforced concrete beams. The self-locking anchoring system of FRP strips and reinforced concrete beams and a construction method thereof are used in combination with serrated steel and self-tapping bolts, FRP cloth, a beam body and a serrated groove. The inner wall of the serrated groove and the bottom of the beam body are filled with epoxy resin adhesive, and then the FRP cloth is longitudinally pasted to the bottom of the beam body along the serrated groove along the length direction of the beam body, and the protruding blocks of the serrated steel are inserted into the inside of the matching serrated groove. At the same time, the FRP cloth is located between the serrated steel and the beam body, and a self-locking anchoring system is formed by passing the self-tapping bolts through the serrated steel, the FRP cloth and the beam body, thereby achieving the goal of enhancing the fixing force of the anchoring, having high anchoring strength and firm structure, effectively preventing the FRP cloth and structural concrete from being peeled off and damaged, improving material utilization and saving construction costs.

Description

Technical Field

[0001] The invention relates to the technical field of concrete structure reinforcement, in particular to a self-locking anchoring system of an FRP strip and a reinforced concrete beam and a construction method thereof. Background Art

[0002] Fiber reinforced composite bars (FRP) are used in pull-out tests, reinforcement projects and prestressed structures in civil engineering. Due to the thermosetting nature of fiber reinforced composite materials, FRP bars have the disadvantages of being brittle and having insufficient transverse shear strength. However, FRP bars have the advantages of high tensile strength, light weight and corrosion resistance. Therefore, an anchoring device for FRP bars can be designed to compensate for the defects of the material, improve the efficiency of FRP anchoring, and make the use of FRP more extensive.

[0003] The existing anchoring methods are mainly adhesive anchors and clamping anchors. However, stress concentration is easily generated under the action of the clamps, which causes damage to the FRP strips and affects the anchoring efficiency. Therefore, it is necessary to improve and develop the existing designs to improve the anchoring efficiency without affecting the properties of the FRP strips themselves.

[0004] At present, FRP cloth is mainly anchored by FRP strips, which increase the bonding area between FRP cloth and concrete by pasting FRP strips perpendicular to the stressed FRP cloth. This anchoring method requires a large amount of FRP strips, and the final main damage mode of FRP cloth is the peeling and damage between the FRP cloth and the FRP strips, resulting in a large amount of material waste. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a self-locking anchoring system of an FRP strip and a reinforced concrete beam and a construction method thereof. The technical problem to be solved by the present invention is that the FRP cloth is mainly anchored by FRP strips, and the bonding area between the FRP cloth and the concrete is increased by pasting FRP strips perpendicular to the stressed FRP cloth. This anchoring method requires a large amount of FRP strips, and the final main damage mode of the FRP cloth is the peeling and damage of the FRP cloth and the FRP strips, resulting in a large amount of material waste.

[0007] (II) Technical solution

[0008] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a self-locking anchoring system of an FRP strip and a reinforced concrete beam, comprising a beam body, an FRP cloth is arranged at the bottom of the beam body, a serrated steel is inserted into the interior of the beam body, and the FRP cloth is located between the serrated steel and the beam body, the left and right sides of the serrated steel are both threadedly connected with self-tapping bolts, and the outer surface of the self-tapping bolts is threadedly connected to the inner part of the beam body, and a serrated groove matching the size of the serrated steel is provided at the bottom of the beam body.

[0009] Preferably, the inner wall of the sawtooth groove and the bottom of the beam body are filled with epoxy resin adhesive, and the FRP cloth is longitudinally adhered and connected to the bottom of the beam body along the length direction of the beam body along the sawtooth groove by the epoxy resin adhesive.

[0010] Preferably, the FRP cloth is glass fiber cloth, aramid fiber cloth or a mixture of glass and aramid fibers.

[0011] Preferably, the width of the sawtooth groove is between 20 mm and 100 mm, and the groove depth of the sawtooth groove is between 10 mm and 20 mm, and the width of the sawtooth groove is equal to the width of the FRP cloth.

[0012] Preferably, the beam body is in the shape of a cuboid, and a thread groove matching the size of the self-tapping bolt is provided inside the beam body.

[0013] Preferably, a construction method of a self-locking anchoring system of FRP strips and reinforced concrete beams comprises the following steps:

[0014] S1: Fill the inner wall of the zigzag groove and the bottom of the beam with epoxy resin adhesive, and then stick the FRP cloth longitudinally along the zigzag groove to the bottom of the beam along the length direction of the beam;

[0015] S2: insert the protruding block of the serrated steel into the matching serrated groove, and place the FRP cloth between the serrated steel and the beam body;

[0016] S3: A self-locking anchoring system is formed by passing self-tapping bolts through the serrated steel and FRP cloth to connect the beam body.

[0017] (III) Beneficial effects

[0018] Compared with the prior art, the present invention provides a self-locking anchoring system of FRP strips and reinforced concrete beams and a construction method thereof, which has the following beneficial effects:

[0019] The self-locking anchoring system of FRP strips and reinforced concrete beams and the construction method thereof are achieved by using serrated steel and self-tapping bolts, FRP cloth, beam body and serrated grooves in combination, the inner wall of the serrated groove and the bottom of the beam body are filled with epoxy resin adhesive, and then the FRP cloth is longitudinally adhered to the bottom of the beam body along the serrated groove along the length direction of the beam body, the protruding blocks of the serrated steel are inserted into the inside of the matching serrated grooves, and the FRP cloth is located between the serrated steel and the beam body, and a self-locking anchoring system is formed by passing self-tapping bolts through the serrated steel, the FRP cloth and the beam body, thereby achieving enhanced anchoring fixing force, high anchoring strength, firm structure, and effective prevention of peeling and damage between the FRP cloth and structural concrete, improving material utilization and saving construction costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the front structure of the present invention;

[0021] Figure 2 It is a bottom view structural schematic diagram of the present invention;

[0022] Figure 3 It is a schematic diagram of the left structure of the present invention.

[0023] In the figure: 1- serrated steel, 2- self-tapping bolts, 3- FRP cloth, 4- beam body, 5- serrated groove. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figure 1-3A self-locking anchoring system of FRP strips and reinforced concrete beams, comprising a beam body 4, an FRP cloth 3 is arranged at the bottom of the beam body 4, a serrated steel 1 is inserted inside the beam body 4, and the FRP cloth 3 is located between the serrated steel 1 and the beam body 4, the left and right sides of the serrated steel 1 are both threadedly connected with self-tapping bolts 2, and the outer surface of the self-tapping bolts 2 is threadedly connected with the internal thread of the beam body 4, and the bottom of the beam body 4 is provided with a serrated groove 5 matching the size of the serrated steel 1. The self-locking anchoring system of FRP strips and reinforced concrete beams and the construction method thereof, through the coordinated use of the serrated steel 1 and the self-tapping bolts 2, the FRP cloth 3, the beam body 4, and the serrated groove 5, through the sawtooth The inner wall of the toothed groove 5 and the bottom of the beam body 4 are filled with epoxy resin adhesive, and then the FRP cloth 3 is longitudinally pasted to the bottom of the beam body 4 along the serrated groove 5 along the length direction of the beam body 4, and the protruding block of the serrated steel 1 is inserted into the inside of the matching serrated groove 5, and the FRP cloth 3 is located between the serrated steel 1 and the beam body 4. A self-locking anchoring system is formed by passing the self-tapping bolts 2 through the serrated steel 1, connecting the FRP cloth 3 and the beam body 4, thereby achieving enhanced anchoring fixing force, high anchoring strength, firm structure, and can effectively prevent the FRP cloth 3 from being peeled off and damaged from the structural concrete, improve material utilization, and save construction costs.

[0026] The inner wall of the sawtooth groove 5 and the bottom of the beam body 4 are filled with epoxy resin adhesive, and the FRP cloth 3 is longitudinally adhered and connected to the bottom of the beam body 4 along the length direction of the beam body 4 along the sawtooth groove 5 through the epoxy resin adhesive.

[0027] The FRP cloth 3 is glass fiber cloth, aramid fiber cloth or a mixture of glass and aramid fibers.

[0028] The width of the zigzag groove 5 is between 50 mm and 100 mm, and the groove depth of the zigzag groove 5 is between 10 mm and 20 mm. The width of the zigzag groove 5 is equal to the width of the FRP cloth 3 .

[0029] The beam body 4 is in the shape of a cuboid, and a thread groove matching the size of the self-tapping bolt 2 is provided inside the beam body 4 .

[0030] A construction method of a self-locking anchoring system of an FRP strip and a reinforced concrete beam comprises the following steps:

[0031] S1: Fill the inner wall of the zigzag groove 5 and the bottom of the beam 4 with epoxy resin adhesive, and then stick the FRP cloth 3 along the length direction of the beam 4 along the zigzag groove 5 to the bottom of the beam 4;

[0032] S2: insert the protruding block of the sawtooth steel 1 into the matching sawtooth groove 5, and at the same time make the FRP cloth 3 located between the sawtooth steel 1 and the beam body 4;

[0033] S3: A self-locking anchoring system is formed by passing the self-tapping bolts 2 through the zigzag steel 1, the FRP cloth 3 and the beam body 4, thereby enhancing the fixing force of the anchoring. The anchoring strength is high and the structure is firm. It can effectively prevent the FRP cloth 3 from being peeled off and damaged from the structural concrete, improve the material utilization rate, and save the construction cost.

[0034] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0035] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A self-locking anchoring system of an FRP strip and a reinforced concrete beam, comprising a beam body (4), characterized in that: The bottom of the beam body (4) is provided with an FRP cloth (3), the interior of the beam body (4) is plugged with a sawtooth steel (1), and the FRP cloth (3) is located between the sawtooth steel (1) and the beam body (4), the left and right sides of the sawtooth steel (1) are both threadedly connected with self-tapping bolts (2), and the outer surface of the self-tapping bolts (2) is threadedly connected with the interior of the beam body (4), and the bottom of the beam body (4) is provided with a sawtooth groove (5) matching the size of the sawtooth steel (1); The inner wall of the sawtooth groove (5) and the bottom of the beam body (4) are filled with epoxy resin adhesive, and the FRP cloth (3) is longitudinally bonded and connected to the bottom of the beam body (4) along the length direction of the beam body (4) along the sawtooth groove (5) by the epoxy resin adhesive; The FRP cloth (3) is glass fiber cloth, aramid fiber cloth or a mixture of glass and aramid fibers.

2. A self-locking anchoring system of FRP strips and reinforced concrete beams according to claim 1, characterized in that: The width of the sawtooth groove (5) is between 50 mm and 100 mm, and the groove depth of the sawtooth groove (5) is between 10 mm and 20 mm. The width of the sawtooth groove (5) is equal to the width of the FRP cloth (3).

3. The self-locking anchoring system of FRP strip and reinforced concrete beam according to claim 1, characterized in that: The beam body (4) is in the shape of a rectangular parallelepiped, and a thread groove matching the size of the self-tapping bolt (2) is provided inside the beam body (4).

4. The construction method of a self-locking anchoring system of FRP strips and reinforced concrete beams according to claim 1, characterized in that: The following steps are involved: S1: The inner wall of the sawtooth groove (5) and the bottom of the beam body (4) are filled with epoxy resin adhesive, and then the FRP cloth (3) is longitudinally adhered to the bottom of the beam body (4) along the length direction of the sawtooth groove (5); S2: inserting the protruding block of the sawtooth steel (1) into the matching sawtooth groove (5), while making the FRP cloth (3) located between the sawtooth steel (1) and the beam body (4); S3: A self-locking anchoring system is formed by passing the self-tapping bolts (2) through the zigzag steel (1), the FRP cloth (3) and the beam body (4).

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