High-stability concrete crack self-healing performance device and method

Abstract

The invention discloses a high-stability concrete crack self-healing performance evaluation device and method.The high-stability concrete crack self-healing performance evaluation device comprises a concrete test block, the concrete test block is divided into two halves through a blocking structure in the forming stage, the two halves of the concrete test block are bonded through a bonding layer, and the top of the concrete test block is sleeved with a sleeve; the upper portion of the sleeve is communicated with the water storage structure, a baffle is arranged on the lower portion in the water storage structure, a through hole is formed in the baffle, and the through hole is matched with the closed structure. According to the crack forming method, variables caused by inconsistent shapes, numbers and widths of cracks are reduced, so that the accuracy of a test result is obviously improved; the device is convenient for researchers to manufacture by themselves, used materials are easy to obtain, and water can flow out at the same time, pressure and flow speed in each test through a closed structure, so that test variables are effectively reduced, and test results are more accurate and persuasive.

Description

Technical Field

[0001] The invention relates to the field of engineering technology, and in particular to a high-stability concrete crack self-healing performance device and method. Background Art

[0002] The research and development of concrete self-healing technology provides new possibilities for extending the service life of concrete structures, reducing maintenance costs and reducing carbon emissions. The concrete self-healing process is extremely complex. Many scholars at home and abroad have conducted in-depth research on it and explored a variety of self-repair technologies, including intrinsic self-repair, permeation crystallization self-repair, electrochemical deposition self-repair, super absorbent polymer self-repair, shape memory alloy self-repair, microcapsule self-repair and microbial self-repair. However, when studying various self-healing technologies, researchers inevitably need to create concrete cracks and evaluate their self-healing ability. When evaluating the self-healing performance of concrete, water permeability test is an economical, convenient and effective method. However, the traditional water permeability test method for evaluating concrete self-healing often involves complex equipment, which makes it difficult for other researchers to replicate, or does not consider the influence of water pressure, further increasing the test variables.

[0003] At present, there is no unified standard for the prefabrication method of concrete cracks and the evaluation method of self-healing ability at home and abroad. Although traditional crack making methods, such as splitting method, three-point bending prefabrication crack method and tensile prefabrication crack method, have been widely used in laboratory environments, they have significant deficiencies in the stability and controllability of crack generation. These methods usually lead to inconsistent crack morphology and difficult to control width, which affects the accuracy and repeatability of test data. For example, the "Standard for Test Methods for Self-Healing Performance of Cement Concrete" (T / CECS 913-2021) uses the splitting method to prefabricate cracks: before loading, the fixture is placed on the lower plate of the press, and then the specimen is placed in the fixture, and slow loading (0.1kN / s) is used until cracks appear. Once cracks appear in the specimen, the loading must be stopped immediately and the specimen must be removed. Subsequently, the sealing tape is wrapped around the circumferential surface of the specimen again to prevent further expansion of the cracks due to external forces during the curing process. However, after practice, the applicant found that this method has the following disadvantages: 1. The crack width cannot be controlled manually; 2. The crack morphology is inconsistent; 3. The accuracy of visual observation of the test block is insufficient, and sometimes the test block has been crushed when the crack is observed; 4. The strength of the manual wrapping tape is inconsistent, which will affect the crack width.

[0004] Therefore, there is an urgent need for a high-stability concrete crack self-healing performance device and method that can solve the problem that the cracks caused by the existing splitting method prefabricated cracks in the water permeability test cannot be controlled artificially, which increases multiple variables and seriously affects the test results. When the water permeability test is used to evaluate the self-healing performance of concrete, it is often necessary to rely on complex equipment, which is difficult for other researchers to replicate, or the influence of water pressure is not fully considered, further increasing the uncertainty of the test. Summary of the invention

[0005] The purpose of the present invention is to provide a high-stability concrete crack self-healing performance device and method to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a high-stability concrete crack self-healing performance evaluation device, comprising a concrete test block, wherein the concrete test block is divided into two halves by a blocking structure in a molding stage, the two halves of the concrete test block are bonded by an adhesive layer, a sleeve is sleeved on the top of the concrete test block, the upper part of the sleeve is connected with a water storage structure, a baffle is provided at the lower part of the water storage structure, a through hole is opened on the baffle, and the through hole cooperates with a closed structure.

[0008] Preferably, the adhesive layer is made of double-sided tape.

[0009] Preferably, the sleeve is a silicone sleeve.

[0010] Preferably, the water storage structure adopts a measuring cylinder.

[0011] Preferably, a connecting plate is provided at the connection between the water storage structure and the sleeve.

[0012] Preferably, the through hole is arranged at the center of the baffle, and its diameter is 5.5 cm.

[0013] Preferably, the closure structure adopts a rubber plug, and a drawstring is fixed on the top of the rubber plug via a connecting nail.

[0014] The present invention also provides a method for evaluating the self-healing performance of high-stability concrete cracks, comprising the following steps:

[0015] S1. Concrete test block forming;

[0016] S2. Paste an adhesive layer between the two halves of the concrete test block to prefabricate the crack;

[0017] S3. Place the concrete test block into the sleeve for water permeability test;

[0018] S4. Obtain test data.

[0019] Preferably, step S1 comprises:

[0020] S11. Insert an acrylic plate of a certain thickness vertically into the middle of the mold;

[0021] S12. pouring concrete into the mold;

[0022] S13. Demoulding after curing.

[0023] Preferably, in step S3, the gap between the concrete test block and the sleeve is filled with sealant.

[0024] Compared with the prior art, the present invention has achieved the following beneficial technical effects:

[0025] The present invention uses double-sided tape to bond two test blocks together, so that the prefabricated concrete cracks are straight and have the same width, and the width and shape of the cracks can be manually controlled, while avoiding the variables caused by the different strengths each time when the tape is manually wrapped. In addition, during the concrete pouring stage, acrylic plates are used for blocking, so that the test blocks can be directly demolded after molding without the use of mold release agents, ensuring that the test blocks are tightly fitted during the prefabricated crack stage, and concrete test blocks molded between different molds can be freely combined. This crack manufacturing method greatly reduces the variables caused by the inconsistency of crack shape, number, and width, thereby significantly improving the accuracy of the test results.

[0026] The device designed by the present invention is easy for researchers to make by themselves, and the materials used are easy to obtain. The device can ensure that water flows out at the same time, pressure and flow rate in each test through a plug mechanism, thereby effectively reducing test variables and making the test results more accurate and more convincing. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 A schematic diagram of the structure of a high-stability concrete crack self-healing performance evaluation device provided by the present invention;

[0029] Figure 2 A flow chart of a method for evaluating the self-healing performance of high-stability concrete cracks provided by the present invention. DETAILED DESCRIPTION

[0030] 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.

[0031] The purpose of the present invention is to provide a high-stability concrete crack self-healing performance device and method to solve the problems existing in the prior art.

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Embodiment 1:

[0034] This embodiment provides a high stability concrete crack self-healing performance evaluation device. Figure 1 As shown, it includes a concrete test block, which is divided into two halves by a blocking structure during the molding stage. The two halves of the concrete test block are bonded by an adhesive layer. A sleeve 1 is provided on the top of the concrete test block, and the upper part of the sleeve 1 is connected to a water storage structure 2. A baffle 3 is provided in the lower part of the water storage structure 2, and a through hole 4 is opened on the baffle 3, and the through hole 4 cooperates with a closed structure 5.

[0035] As an implementation manner, the adhesive layer uses double-sided tape.

[0036] As an implementation mode, the sleeve 1 is a silicone sleeve.

[0037] As an implementation mode, the water storage structure 2 adopts a measuring cylinder.

[0038] As an implementation mode, a connecting plate 6 is provided at the connection between the water storage structure 2 and the sleeve 1 .

[0039] As an implementation manner, the through hole 4 is arranged at the center of the baffle, and its diameter is 5.5 cm.

[0040] As an implementation mode, the closing structure 5 is a rubber plug, and a drawstring 7 is fixed to the top of the rubber plug via a connecting nail.

[0041] The present invention also provides a method for evaluating the self-healing performance of high-stability concrete cracks. Figure 2 As shown, the following steps are included:

[0042] S1. Concrete test block forming; specifically:

[0043] S11. Insert an acrylic sheet of a certain thickness vertically in the middle of the mold to prevent the hardness from being insufficient and affecting the use. It is also necessary to note that the size of the acrylic sheet should be accurate and the acrylic sheet should be stuck in the mold to avoid leakage and ensure the consistency of concrete molding. This step is to divide the concrete into two halves in the same mold for use when prefabricating cracks;

[0044] S12. pouring concrete into the mold;

[0045] S13. Demolding after curing;

[0046] S2. Paste an adhesive layer between the two halves of the concrete test block to form a prefabricated crack, and paste double-sided tape at both ends in the middle of the two test blocks to make them tightly combined into a complete test block. The width of the prefabricated crack can be controlled by adjusting the number of layers of tape. After practice, the applicant found that materials such as ordinary double-sided tape and nano tape usually cannot be directly adhered to the concrete surface, but the adhesion can be enhanced after applying an adhesion promoter on the concrete bonding surface. Multiple tests have shown that the double-sided tape of the Benyida brand product number 10114612759431 and the single-sided tape of the Xuanjia Mittal brand product number 100060573739 can be directly bonded to the concrete test block without the need for an adhesion promoter. Among them, the single-sided tape of Xuanjia Mittal has the strongest bonding ability. If single-sided tape is used, single-sided tape needs to be pasted at both ends in the middle of the two test blocks, and another double-sided tape needs to be pasted in the middle;

[0047] S3. Place the concrete test block into the sleeve for water permeability test; use Xuanjia Mital brand 3x0 grade mildew-proof sealant to seal all gaps except the precast concrete cracks to prevent water from flowing out from other gaps;

[0048] It should be noted that: 1. Make sure that the measuring cylinder has enough volume to accommodate the test water; 2. The through hole is large enough to allow enough water to flow out to ensure that the water permeability test can be carried out normally;

[0049] S4. Obtain test data.

[0050] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A high stability concrete crack self-healing performance evaluation device, characterized by: It includes a concrete test block, which is divided into two halves by a blocking structure during the molding stage, and the two halves of the concrete test block are bonded by an adhesive layer, a sleeve is provided on the top of the concrete test block, and the upper part of the sleeve is connected to a water storage structure, a baffle is provided in the lower part of the water storage structure, a through hole is opened on the baffle, and the through hole cooperates with the closed structure.

2. The high stability concrete crack self-healing performance evaluation device according to claim 1, characterized in that: The adhesive layer adopts double-sided adhesive.

3. The high stability concrete crack self-healing performance evaluation device according to claim 1, characterized in that: The sleeve is a silicone sleeve.

4. The high stability concrete crack self-healing performance evaluation device according to claim 1, characterized in that: The water storage structure adopts a measuring cylinder.

5. The high stability concrete crack self-healing performance evaluation device according to claim 1, characterized in that: A connecting plate is provided at the connection between the water storage structure and the sleeve.

6. The high stability concrete crack self-healing performance evaluation device according to claim 1, characterized in that: The through hole is arranged at the center of the baffle, and has a diameter of 5.5 cm.

7. The high stability concrete crack self-healing performance evaluation device according to claim 1, characterized in that: The closure structure adopts a rubber plug, and a drawstring is fixed on the top of the rubber plug through a connecting nail.

8. A method for evaluating the self-healing performance of high-stability concrete cracks, characterized in that: The following steps are involved: S1. Concrete test block forming; S2. Paste an adhesive layer between the two halves of the concrete test block to prefabricate the crack; S3. Place the concrete test block into the sleeve for water permeability test; S4. Obtain test data.

9. The method for evaluating the self-healing performance of cracks in high stability concrete according to claim 8, characterized in that: Step S1 includes: S11. Insert an acrylic plate of a certain thickness vertically into the middle of the mold; S12. pouring concrete into the mold; S13. Demoulding after curing.

10. The method for evaluating the self-healing performance of cracks in high stability concrete according to claim 8, characterized in that: In step S3, the gap between the concrete test block and the sleeve is filled with sealant.

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