A mechanical properties testing system for CFRP bars in a corrosive environment

Abstract

A mechanical property test system for CFRP bars in a corrosive environment includes a preparation module, a corrosion sampling module, a calculation module, a pull-out test module, and a data analysis module, characterized in that the preparation module includes a cutter, the corrosion sampling module includes a corrosion device, and the pull-out test module includes a tensile machine. The present invention completes the mechanical property test of CFRP bars in a corrosive environment according to the corrosion rate and the stress-strain change rate curve obtained under different corrosion degrees. The connection between the corrosion rate and the mechanical property of the steel bar can be established by collecting and analyzing data, which can provide effective data and methods for the evaluation of CFRP bars in actual projects. The present invention can perform reliable and effective mechanical testing on CFRP bar specimens.

Description

Technical Field

[0001] The invention belongs to mechanical property testing, and in particular relates to a mechanical property testing system for CFRP bars in a corrosive environment. Background Art

[0002] Carbon fiber reinforced composite material (CFRP) is a new type of non-metallic composite reinforcement material composed of multiple continuous fibers and a resin matrix. It has excellent mechanical properties such as high corrosion resistance, high tensile strength, good creep relaxation performance, light weight, and strong fatigue resistance. It has good application prospects in corrosive environments and special environmental engineering. It is also often used as prestressed reinforcement in prestressed concrete structures. As the main load-bearing component, the bearing capacity of CFRP reinforcement is largely determined by the performance of the anchor.

[0003] The plasticity of CFRP tendons deteriorates after corrosion. The more severe the corrosion, the greater the cross-sectional loss rate, and the more severe the plasticity reduction. The yield strength of corroded CFRP tendons decreases, and the degree of reduction varies linearly with the cross-sectional loss rate. The reduction in the yield strength of corroded CFRP tendons directly affects the resistance of the service structure, and in severe cases may cause the structure to collapse.

[0004] Due to the corrosion resistance of CFRP bars, a test system is needed to obtain the mechanical properties of CFRP bars in different corrosion environments and corrosion degrees to evaluate the reasonable use of CFRP bars in different fields. The existing test systems also have many inconvenient factors such as unstable test loading, inconvenient installation of test instruments, complicated experimental steps, and complex operations. Therefore, it is necessary to find a simple and suitable test system for the mechanical properties of CFRP bars in a corrosive environment. Summary of the invention

[0005] The above-mentioned invention object of the present invention is achieved through the following technical solutions:

[0006] A mechanical property testing system for CFRP bars in a corrosion environment comprises a preparation module, a corrosion sampling module, a calculation module, a drawing test module and a data analysis module, wherein the preparation module comprises a cutting machine, the corrosion sampling module comprises a corrosion device and the drawing test module comprises a tensile machine.

[0007] Preferably, a preparation module is used to prepare standard experimental samples of CFRP bars, and to prepare electrolytes for corrosion modules;

[0008] The corrosion sampling module is used to accelerate corrosion by electrochemical corrosion and is equipped with a corrosion device to record the corrosion time, current and corrosion environment;

[0009] A calculation module is used for calculating the corrosion rate of the sample according to Faraday's law with the corrosion time and the current size;

[0010] The pulling test module is used to obtain the stress, strain and displacement data parameters of the CFRP bar test samples after different corrosion conditions;

[0011] The data analysis module is used to analyze the obtained data, obtain the stress-strain change rate curve under different corrosion degrees according to the corrosion degree and stress-strain or relationship curve, and complete the mechanical properties test of CFRP bars in a corrosive environment.

[0012] Preferably, the corrosion device includes a base, which is a semicircular structure, and electrochemical reaction cells are evenly arranged on the base. A rust removal area is also arranged on one side of the base, and a cleaning liquid is arranged below the rust removal area. A clamping and rotating device is arranged at one end of the electrochemical reaction cell close to the rust removal area, and the base is provided with a controller and a power supply.

[0013] Preferably, the clamping and rotating device includes a support column, a clamping rod and an active rod, the support column fixes the clamping rod to one side of the electrochemical reaction cell, the other end of the clamping rod is provided with a driven rod, the driven rod is provided with a bevel gear 1, and a bevel gear 2 is provided under the active rod, the bevel gear 1 and the bevel gear 2 match each other, the clamping rod is provided with a clamping hole, the sample to be corroded can be placed in the clamping hole, the clamping rod is also provided with a fixing hole, the fixing hole is provided with a bolt, the bolt can lock the sample to be corroded in the fixing hole, and the clamping and rotating device can rotate around the clamping rod.

[0014] Preferably, the rust removal area includes a sandblasting rust removal device, which includes a sandblasting head and a water spray head. The sandblasting head and the water spray head are connected to the sandblasting motor through a pipeline, and can be removed to perform sandblasting rust removal and cleaning on the sample to be corroded. The rust removal area is also provided with a support frame, which matches the clamping and rotating device. The support frame includes a support base, which is fixed on the base, and a support group is provided above the support base. The support group and the support base are rotatably connected through a rotating rod, and a return spring is also provided on the rotating rod. A support guide ball is provided at the upper end of the support group, and a clamping device is also provided on the side of the support group, and the clamping device is provided with an ultrasonic vibrator. .

[0015] In summary, the present invention includes at least one of the following beneficial technical effects:

[0016] The present invention completes the mechanical property test of CFRP bars in a corrosive environment according to the corrosion rate and the stress-strain change rate curves obtained under different corrosion degrees. The relationship between the corrosion rate and the mechanical properties of the steel bars can be established through data collection and analysis, which can provide effective data and methods for the evaluation of CFRP bars in actual projects. The present invention can perform reliable and effective mechanical testing on CFRP bar specimens.

[0017] The present invention is also equipped with a corrosion device for laboratory use, which can solve the problem that under accelerated corrosion, the continuous generation of corrosion rust will slow down the subsequent corrosion rate, affecting the efficiency of the test. Through the setting of the corrosion device, a simple structure can be used to achieve the requirements of multiple samples and rapid corrosion required by laboratory data. It is an indispensable device for the experimental process, more samples can be obtained at one time, and the time to obtain the desired corrosion level can be shortened to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a system schematic diagram of a mechanical property testing system of a CFRP bar in a corrosive environment of the present invention;

[0019] Figure 2 It is an overall schematic diagram of a corrosion device of a mechanical property testing system of a CFRP bar in a corrosive environment according to the present invention;

[0020] Figure 3 The present invention is a mechanical performance testing system for CFRP bars in a corrosive environment. Figure 2 An enlarged schematic diagram of "E";

[0021] Figure 4 It is a schematic diagram of a clamping and rotating device of a mechanical property testing system of a CFRP bar in a corrosive environment of the present invention;

[0022] Figure 5 It is a schematic diagram of the rust removal state of a mechanical property testing system of a CFRP bar in a corrosive environment according to the present invention;

[0023] Figure 6 It is a schematic diagram of the support frame structure of a mechanical property testing system of CFRP bars in a corrosive environment according to the present invention;

[0024] Figure 7 It is a cross-sectional schematic diagram of a support frame of a mechanical property testing system of a CFRP bar in a corrosive environment according to the present invention;

[0025] Figure 8 It is a cross-sectional schematic diagram of a support frame of a mechanical property testing system of CFRP bars in a corrosive environment of the present invention when it is in a sunken state.

[0026] In the figure: 1 base, 2 electrochemical reaction cell, 3 rust removal area, 301 sandblasting rust removal device, 302 sandblasting head, 303 water spray head, 4 clamping and rotating device, 401 support column, 402 clamping rod, 403 active rod, 404 driven rod, 405 bevel gear 1, 406 bevel gear 2, 407 clamping hole, 408 fixing hole, 409 bolt, 5 support frame, 501 support base, 502 support group, 503 rotating rod, 504 return spring, 505 support guide ball, 506 clamping device. DETAILED DESCRIPTION

[0027] The above-mentioned inventive object of the present invention is achieved through the following technical scheme: a mechanical properties testing system for CFRP bars in a corrosive environment, comprising a preparation module, a corrosion sampling module, a calculation module, a pulling test module, and a data analysis module, wherein: the preparation module comprises a cutting machine, the corrosion sampling module comprises a corrosion device, and the pulling test module comprises a tensile machine.

[0028] Preferably, a preparation module is used to prepare standard experimental samples of CFRP bars, and to prepare electrolytes for corrosion modules;

[0029] The corrosion sampling module is used to accelerate corrosion by electrochemical corrosion and is equipped with a corrosion device to record the corrosion time, current and corrosion environment;

[0030] A calculation module is used for calculating the corrosion rate of the sample according to Faraday's law with the corrosion time and the current size;

[0031] The pulling test module is used to obtain the stress, strain and displacement data parameters of the CFRP bar test samples after different corrosion conditions;

[0032] The data analysis module is used to analyze the obtained data, obtain the stress-strain change rate curve under different corrosion degrees according to the corrosion degree and stress-strain or relationship curve, and complete the mechanical properties test of CFRP bars in a corrosive environment.

[0033] Preferably, the corrosion device includes a base 1, which is a semicircular structure, and electrochemical reaction cells 2 are evenly arranged on the base 1. A rust removal area 3 is also arranged on one side of the base 1, and a cleaning liquid is arranged below the rust removal area 3. A clamping and rotating device 4 is arranged at one end of the electrochemical reaction cell 2 close to the rust removal area 3, and the base 1 is provided with a controller and a power supply.

[0034] Preferably, the clamping and rotating device 4 includes a support column 401, a clamping rod 402 and an active rod 403, the support column 401 fixes the clamping rod 402 to one side of the electrochemical reaction cell 2, and the other end of the clamping rod 402 is provided with a driven rod 404, and the driven rod 404 is provided with a bevel gear 1 405, and a bevel gear 2 406 is provided below the active rod 403, and the bevel gear 1 405 and the bevel gear 2 406 match each other, and the clamping rod 402 is provided with a clamping hole 407, and the sample to be corroded can be placed in the clamping hole 407, and the clamping rod 402 is also provided with a fixing hole 408, and the fixing hole 408 is provided with a bolt 409, and the bolt 409 can lock the sample to be corroded in the fixing hole 408, and the clamping and rotating device 4 can rotate around the clamping rod 401.

[0035] Preferably, the rust removal area 3 includes a sandblasting rust removal device 301, and the sandblasting rust removal device 301 includes a sandblasting head 302 and a water spray head 303. The sandblasting head 302 and the water spray head 303 are connected to the sandblasting motor through a pipeline, and can be removed to perform sandblasting rust removal and cleaning on the corrosion sample respectively. The rust removal area 3 is also provided with a support frame 5, and the support frame 5 is matched with the clamping and rotating device 4. The support frame 5 includes a support base 501, and the support base 501 is fixed on the base 1. A support group 502 is arranged above the support base 501, and the support group 502 is rotatably connected to the support base 501 through a rotating rod 503. A return spring 504 is also arranged on the rotating rod 503, and a support guide ball 505 is arranged on the upper end of the support group 502. A clamping device 506 is also arranged on the side of the support group 502, and the clamping device 506 is provided with an ultrasonic vibrator.

[0036] Working principle: Pour electrochemical solutions of different proportions into each electrochemical reaction cell respectively, and obtain 50mm long CFRP tendon samples through the preparation module, and put them into the clamping holes in turn, and tighten the bolts at the same time so that the CFRP tendon samples can be fastened to the clamping holes. At this time, turn the active rod, and the sample will rotate and sink into the electrochemical reaction cell. At this time, the power supply is turned on to accelerate the corrosion reaction. At the same time, after a certain interval, turn the active rod to rotate the sample 180°. At this time, the sample is transferred to the rust removal area. The staff takes the sandblasting head and uses the sandblasting rust removal device to remove the rust on the surface of the corroded sample. Then continue to turn the active rod, and the sample will support The support group is pressed down and rotated by the rotating rod, so that the sample enters the cleaning liquid below and is limited by the clamping device at the final position. At this time, the sample is further cleaned by the ultrasonic vibrator, and then the cleaning liquid surface is ejected by the elastic force of the return spring, and the sample is rotated back to the electrochemical reaction cell for further corrosion by the active rod. At this time, since there is no rust on the surface of the CFRP tendon sample, the electrochemical corrosion rate will not be affected, which speeds up the time to obtain samples with the required corrosion degree. At the same time, the design of multiple electrochemical reaction cells can meet the corrosion of multiple samples in different environments at the same time, greatly speeding up the corrosion time required for the experiment.

[0037] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A mechanical properties testing system for CFRP bars in a corrosive environment, comprising a preparation module, a corrosion sampling module, a calculation module, a drawing test module, and a data analysis module, characterized in that: The preparation module includes a cutting machine, the corrosion sampling module includes a corrosion device, and the drawing experiment module includes a tensile machine; Preparation module, used to prepare standard experimental samples of CFRP bars and prepare electrolyte for corrosion module; The corrosion sampling module is used to accelerate corrosion by electrochemical corrosion and is equipped with a corrosion device to record the corrosion time, current and corrosion environment; A calculation module is used for calculating the corrosion rate of the standard experimental sample according to Faraday's law with the corrosion time and current size; The pulling test module is used to obtain the stress, strain and displacement data parameters of the CFRP bar test samples after different corrosion conditions; A data analysis module is used to analyze the acquired data, obtain stress-strain change rate curves under different corrosion degrees according to the corrosion degree and stress-strain or relationship curves, and complete the mechanical property test of the CFRP bar under a corrosion environment; the corrosion device comprises a base (1), the base (1) is a semicircular structure, electrochemical reaction cells (2) are evenly arranged on the base (1), a rust removal area (3) is also arranged on one side of the base (1), a cleaning liquid is arranged below the rust removal area (3), a clamping and rotating device (4) is arranged at one end of the electrochemical reaction cell (2) close to the rust removal area (3), and the base (1) is provided with a controller and a power supply; The clamping and rotating device (4) comprises a support column (401), a clamping rod (402) and an active rod (403), wherein the support column (401) fixes the clamping rod (402) to one side of the electrochemical reaction cell (2), a driven rod (404) is arranged at the other end of the clamping rod (402), a bevel gear 1 (405) is arranged on the driven rod (404), and a bevel gear 2 (406) is arranged below the active rod (403), and the bevel gear 1 (406) is arranged at the bottom of the active rod (403). 5) is matched with the second bevel gear (406), the clamping rod (402) is provided with a clamping hole (407), the sample to be corroded can be placed in the clamping hole (407), the clamping rod (402) is also provided with a fixing hole (408), the fixing hole (408) is provided with a bolt (409), the bolt (409) can lock the sample to be corroded in the fixing hole (408), and the clamping rotating device (4) can rotate around the clamping rod (402).

2. The mechanical properties testing system of a CFRP bar in a corrosive environment according to claim 1, characterized in that: The rust removal area (3) includes a sandblasting rust removal device (301), the sandblasting rust removal device (301) includes a sandblasting head (302) and a water spray head (303), the sandblasting head (302) and the water spray head (303) are both connected to the sandblasting motor through a pipeline, and can be removed to perform sandblasting rust removal and cleaning on the corrosion sample respectively. The rust removal area (3) is also provided with a support frame (5), the support frame (5) matches the clamping and rotating device (4), the support frame (5) includes a support base (501), the support frame (5) is provided with a support frame (502), and the support frame (5) is provided with a support frame (501). The support base (501) is fixed on the base (1); a support group (502) is arranged above the support base (501); the support group (502) and the support base (501) are rotatably connected via a rotating rod (503); a return spring (504) is also arranged on the rotating rod (503); a support guide ball (505) is arranged at the upper end of the support group (502); a clamping device (506) is also arranged on the side of the support group (502); and the clamping device (506) is provided with an ultrasonic vibrator.

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