An experimental device and experimental method for the repair performance of concrete cracks

Abstract

The present invention discloses a test device and a test method for the repair performance of concrete cracks, including a rectangular space formed by a lower bottom plate, a pair of long baffles, and a pair of short baffles; a pair of crack-inducing upper plates and crack-inducing lower plates are provided in the middle of the long baffles, and tension rods are respectively inserted in the middle of the short baffles; the structure of this test device is simple, easy to assemble and disassemble, and can be reused repeatedly; when concrete is poured into this test device, through the setting of the pair of crack-inducing upper plates, the concrete can generate cracks with uniform cross-sections at specific positions, and it can ensure that the test device is reassembled into the original fixed mode; after the repair material test, through the vacant positions after the disassembly of the original crack-inducing upper plates and crack-inducing lower plates, the repair effect can be visually observed. The operation process is simple, the effect is easy to obtain, and it is applicable to the inspection of various repair materials.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete performance test devices, and particularly relates to a test device and a test method for the crack repair performance of concrete. Background Art

[0002] Concrete is a very widely used material, but it is a brittle material with low tensile strength. During its hardening process, when the stress generated by the shrinkage of concrete under constrained conditions exceeds the tensile strength of concrete, cracks will occur in the concrete. The cracks in concrete have a significant impact on the waterproofness and durability of concrete. No matter how good the impermeability and corrosion resistance of concrete are, once cracks occur, corrosive media such as chloride ions will directly reach the surface of the steel bars through the cracks, thereby causing corrosion of the steel bars in the concrete, generating volume expansion, and ultimately leading to the destruction of the reinforced concrete structure. In order to enable concrete to continue to be used normally, some materials for repairing concrete cracks are developing rapidly, but the testing methods and testing equipment and instruments are very limited. In order to verify the repair effect of the repair material on concrete cracks, it is necessary to artificially create cracks in the concrete before testing, and at the same time, it is necessary to facilitate the follow-up and detection of the subsequent effects, which is the key point in testing the repair performance.

[0003] The Chinese utility model patent (publication number: CN209148688U) disclosed an adjustable test device for the early anti-cracking performance of concrete in 2019, which includes a bottom plate and two long side plates and two short side plates surrounding the bottom plate. There are uniform scale lines on the long side plates, fixing plates are provided at both ends of the long side plates, a long screw rod is welded at both ends of the short side plates, 6 threaded holes are evenly distributed horizontally on the short side plates, and length-adjustable limiters are inserted into the threaded holes. The short side plates and the long side plates are connected by screw rods. 3 stress induction generators are evenly distributed in the middle of the bottom plate. The stress induction generator includes a first steel plate and a second steel plate. One end of the first steel plate and the second steel plate is slidably connected to the bottom plate, and the other end is connected by a rotating shaft. Telescopic rods are provided at both ends of the rotating shaft, and the telescopic rods are connected to the bottom plate. This experimental device can cause the test piece to crack quickly under the same other test conditions, but it is impossible to conduct a performance test on the cracked concrete test piece after repairing with a crack repair material, and other devices need to be used to conduct the crack repair performance test.

[0004] At present, in the detection standards of some materials, such as the "Technical Specification for Application of Inorganic Waterborne Penetrating Crystalline Materials" T / CECS 848-2021, a test method for the mortar crack repair performance is introduced. For the formed specimens, a 2-mm-deep indentation is sawn along the midline on the forming surface. After curing, they are broken along the fold line, and the cross-sections are glued tightly. A graduated cylinder is hermetically pasted on the non-forming surface to add the repair material. After a certain period of time, the effect of the material is judged by observing whether there is moisture stain at the lower part. This method is currently only applicable to mortar, and there are certain differences from the actual application object of the repair material, namely concrete. In addition, the cross-sectional morphology of the broken mortar specimens appears relatively randomly, the operation is relatively complex, and the effect is greatly affected. Finally, there are many types of repair materials, and this method is only applicable to this type of penetrating material and is not suitable for the difference comparison between other materials. Summary of the Invention

[0005] The object of the present invention is to provide a test device and a test method for the concrete crack repair performance in view of the problems existing in the prior art.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A test device for the concrete crack repair performance includes a lower base plate. A pair of long-side baffles are symmetrically arranged on the lower base plate along the length direction, and a pair of short-side baffles are symmetrically arranged on the lower base plate along the width direction. The long-side baffles, the short-side baffles and the lower base plate are detachably connected together to form a rectangular space with an open upper part. In the middle of the long-side baffle, there is an induction plate installation hole with a triangle at the upper part and a rectangle at the lower part. Outside the induction plate installation hole, there are a pair of inclined connecting plates and a pair of vertical connecting plates. The pair of inclined connecting plates are arranged along the hypotenuse of the triangle, and the vertical connecting plates are arranged along the opposite sides of the rectangle and are located below the inclined connecting plates. A crack induction upper plate and a crack induction lower plate spanning the rectangular space are inserted into the pair of induction plate installation holes. The crack induction upper plate is a pair, spliced into an inverted "V" shape structure. The two ends of the crack induction upper plate are respectively detachably connected to the inclined connecting plates. The crack induction lower plate is also a pair, respectively vertically arranged below the crack induction upper plate. The two ends of the crack induction lower plate are respectively detachably connected to the vertical connecting plates. The crack induction lower plate is arranged parallel to the short-side baffle, and a tension rod is respectively inserted into the middle of the short-side baffle.

[0008] The test device has a simple structure, is easy to assemble and disassemble, is convenient to use, and can be repeatedly combined to form a rectangular space with basically the same size; concrete is poured in the test device, and a pair of crack inducing upper plates are set to enable the concrete to produce cracks with uniform cross-sections at specific positions, and the test device can be reassembled into the original fixed mode. After the repair material test, the repair effect can be visually observed through the empty space after the original crack inducing upper plate and the crack inducing lower plate are disassembled. The operation is simple, the effect is easy to obtain, and it is suitable for the inspection of a variety of repair materials.

[0009] The structure in which the long baffle plate and the short baffle plate are connected to the lower base plate can be fixed by bolts. Corresponding screw holes are provided on each plate. The screw holes on each side can be directly screwed in after they correspond to each other. No other positioning and fixing parts are required. The structure can be disassembled and repeatedly connected for use, with a high degree of restoration.

[0010] The induction plate mounting hole is arranged in the middle of the longitudinal baffle, so that the induction plates can be arranged in the middle, so that the fracture site of the concrete specimen is in the middle, which has a better guiding and position selection effect. The crack induction lower plate and the crack induction upper plate are respectively arranged as a pair of independent ones, which are convenient for sequential installation and removal without interfering with each other. They can be installed according to the shape and position of the induction plate mounting hole, and can be directly pulled out when removed.

[0011] The oblique connection plate and the vertical connection plate are used to connect and fix the crack inducing upper plate and the crack inducing lower plate respectively, and have guiding and positioning functions.

[0012] Inserting the tension rods horizontally and vertically into the short baffles enables the formed concrete specimens to have tension rods at both ends, which facilitates direct pulling on the testing machine; and such an arrangement will not affect the removal of the short baffles.

[0013] When pouring concrete, the crack inducing upper plate and the crack inducing lower plate are both installed in the rectangular space, so that the formed concrete specimen has a uniform inverted V-shaped groove underneath, which is conducive to the generation of cracks in the concrete specimen during pulling, reduces damage in other positions, and avoids the falling of irregular soil blocks to avoid difficulties in splicing and restoration; when testing crack repair materials, the crack inducing upper plate and lower plate do not need to be installed after the rectangular space is assembled, and the space left empty is convenient for observing leakage conditions.

[0014] Furthermore, first wing plates are respectively provided on both sides and the bottom of the long baffle, the first wing plates on both sides are respectively screwed and fixed to the two sides of the short baffle, the first wing plates at the bottom are screwed and fixed to the lower bottom plate, and the first wing plates at the bottom are all extended to the vertical connecting plate and connected together.

[0015] The first wing plates are all arranged on the outside, facilitating docking and installation. Moreover, the first wing plates at the bottom can increase the bottom support area of the long baffle, enabling it to stand vertically on the lower bottom plate, which is convenient for subsequent fixed connection with bolts.

[0016] The first wing plate, the inclined connecting plate, the vertical connecting plate and the long baffle are of an integrally formed structure, or an integral structure formed by welding steel plates of various shapes. Such a structure has high stability and is durable.

[0017] Furthermore, second wing plates are respectively provided at the bottoms of the short baffles. The second wing plates are respectively screwed and fixed to the lower bottom plate. The length of the short baffle is greater than the distance between a pair of the long baffles.

[0018] The second wing plates are also of an integral structure with the short baffles. The setting of the second wing plates also facilitates the installation of the short baffles. The positions for bolt connection are all arranged on the outside, which is convenient for operation.

[0019] Furthermore, openings are provided in the middle of the short baffles. The tension rods are inserted into the openings. The aperture of the openings is larger than the outer diameter of the tension rods. Such a setting facilitates the insertion of the tension rods and also facilitates the removal of the short baffles.

[0020] Furthermore, the included angle between a pair of the crack-inducing upper plates is 90 degrees. The docking intersection line of a pair of the crack-inducing upper plates is located at the exact middle of the rectangular space. Such settings of the angle and position can induce cracks to break in the middle. The symmetric settings on both sides result in more balanced stress, which is conducive to the formation of regular cracks.

[0021] Furthermore, the bottom of the induction plate mounting hole is open. The vertex position of the induction plate mounting hole is located at 50%-90% of the vertical height of the long baffle. This can ensure a certain thickness at the crack induction part without being too large.

[0022] Furthermore, the crack-inducing lower plate and the crack-inducing upper plate have the same length, and both are longer than the length of the short baffle. Both ends of the crack-inducing lower plate and the crack-inducing upper plate extend beyond the inclined connecting plate.

[0023] Such a setting can ensure that both ends of the crack-inducing upper plate are exposed for subsequent disassembly. The setting of the crack-inducing lower plate can support the crack-inducing upper plate. At the same time, together with the crack-inducing upper plate, it makes the interior of the rectangular space a closed structure, so that it can be used to fill concrete.

[0024] Furthermore, the cross-section of the crack-inducing upper plate is an isosceles trapezoid, with the lower base angle of the isosceles trapezoid being 45 degrees, and the length of the lower base of the isosceles trapezoid being the same as the hypotenuse length of the induction plate mounting hole. Such a crack-inducing upper plate has a certain thickness and ensures strength. Setting its cross-sectional shape as an isosceles trapezoid facilitates the formation of the included angle and can also closely cooperate with the induction plate mounting hole and the inclined connecting plate.

[0025] Furthermore, the cross-section of the crack-inducing lower plate is rectangular, and the side length of the rectangle is the same as the length of the vertical side of the induction plate mounting hole.

[0026] Furthermore, a test method for the concrete crack repair performance, the test method includes the following steps:

[0027] Step 1: Use bolts to fixedly connect the long baffle with the lower bottom plate, the short baffle with the lower bottom plate, and the long baffle with the short baffle to form a rectangular space with an upper opening;

[0028] Step 2: Insert the crack-inducing upper plate and the crack-inducing lower plate into the induction plate mounting hole in sequence, penetrate a pair of the long baffles, adjust the included angle between a pair of the crack-inducing upper plates to 90 degrees and fix it with bolts;

[0029] Step 3: Insert the tension rods into the short baffles respectively and fix the tension rods on the outside; Apply a coating agent in the connected test device, pour concrete with a specified mix ratio, and cure it under standard conditions;

[0030] Step 4: After curing, loosen all the connected bolts, take out the crack-inducing upper plate and the crack-inducing lower plate in sequence, and remove the short baffle and the long baffle to obtain a concrete specimen with tension rods at both ends;

[0031] Step 5: Place the concrete specimen in step 4 on a concrete testing machine, that is, fix the tension rods on the concrete specimen on the concrete testing machine and break the concrete specimen;

[0032] Step 6: Reassemble and fix the broken concrete specimen in the test device, that is, fix the short baffle with the lower bottom plate, the short baffle with the long baffle, the long baffle with the lower bottom plate, and the tension rods with the short baffle respectively, so that the broken and spliced concrete specimen returns to the fixed mode before the test;

[0033] Step 7: Spray or coat a crack repair material on the crack of the broken concrete specimen and cure it;

[0034] Step 8: After reaching the time specified for the construction of the repair material, sprinkle water on the crack and observe whether there is water seepage under the positions of the original crack-induced upper plate and lower plate. No water seepage and wet stains indicate the effectiveness of the crack repair material.

[0035] By operating the described test method, a concrete specimen with a relatively stable crack fracture surface can be obtained. In this way, when conducting the performance test of the crack repair material, the error is small, the influence on the test result is small, and the forming of the concrete specimen and the observation of crack penetration can be carried out using the same test device.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The structure of this test device is simple, easy to assemble and disassemble, convenient to use, and can be repeatedly combined to form a rectangular space with basically the same size; by pouring concrete into this test device and setting a pair of the crack-induced upper plates, the concrete can generate cracks with uniform cross-sections at specific positions, and it can ensure that the test device is reassembled into the original fixed mode; after the repair material test, through the vacant positions after the disassembly of the original crack-induced upper plate and the crack-induced lower plate, the repair effect can be directly observed; 2. The operation of the described test method is simple, the effect is easy to obtain, and it is applicable to the inspection of various repair materials; 3. The described test method can obtain a concrete specimen with a relatively stable crack fracture surface. In this way, when conducting the performance test of the crack repair material, the error is small, the influence on the test result is small; 4. Both the long-side baffle and the short-side baffle are connected to the lower bottom plate by bolts. Without the use of other positioning and fixing components, they can be disassembled and repeatedly connected for use, with a high reduction degree; 5. The crack-induced lower plate and the crack-induced upper plate are respectively a pair of independent settings, which are convenient for sequential installation and disassembly, do not interfere with each other, and can be installed according to the shape and position of the induced plate installation holes, and can be directly pulled outwards when disassembling; by horizontally and vertically inserting the tension rods on the short-side baffle, the formed concrete specimen can have tension rods at both ends, which is convenient for directly pulling and breaking on the testing machine. Description of the Drawings

[0037] Figure 1 It is a schematic diagram of the overall structure of a test device for the concrete crack repair performance of the present invention;

[0038] Figure 2 It is a schematic perspective view of the overall structure of a test device for the concrete crack repair performance of the present invention;

[0039] Figure 3 It is a schematic diagram of the structure of the long-side baffle of a test device for the concrete crack repair performance of the present invention;

[0040] Figure 4 It is a schematic diagram of the structure of the short-side baffle of a test device for the concrete crack repair performance of the present invention;

[0041] Figure 5 Schematic structural diagram of the crack induction upper plate of an experimental device for the concrete crack repair performance of the present invention;

[0042] Figure 6 Cross-sectional structural diagram of the crack induction upper plate of an experimental device for the concrete crack repair performance of the present invention;

[0043] Figure 7 Schematic structural diagram of the crack induction lower plate of an experimental device for the concrete crack repair performance of the present invention;

[0044] In the figure: 1. Longitudinal baffle; 101. Inducing plate mounting hole; 102. Oblique connecting plate; 103. Vertical connecting plate; 104. First wing plate; 2. Transverse baffle; 201. Second wing plate; 202. Opening; 3. Lower bottom plate; 4. Crack induction upper plate; 5. Crack induction lower plate; 6. Bolt; 7. Tension rod. Detailed implementation manners

[0045] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0046] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "middle", "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0047] Embodiment 1:

[0048] As Figures 1 to 4As shown, a test device for concrete crack repair performance comprises a lower base plate 3, wherein a pair of long baffles 1 are symmetrically provided along the length direction on the lower base plate 3, and a pair of short baffles 2 are symmetrically provided along the width direction on the lower base plate 3, wherein the long baffles 1, the short baffles 2 and the lower base plate 3 are detachably connected together to form a rectangular space with an upper opening; an induction plate mounting hole 101 having a triangular shape on the upper side and a rectangular shape on the lower side is provided in the middle of the long baffle 1, and a pair of oblique connecting plates 102 and a pair of vertical connecting plates 103 are provided on the outer side of the induction plate mounting hole 101, wherein the pair of oblique connecting plates 102 are arranged along the hypotenuse of the isosceles triangle, and the vertical connecting plates 103 are arranged along the The opposite sides of the rectangle are arranged and set below the oblique connecting plate 102; a pair of the induction plate mounting holes 101 are inserted with a crack inducing upper plate 4 and a crack inducing lower plate 5 spanning the rectangular space, the crack inducing upper plate 4 is a pair, spliced into an inverted "V" shape structure, the two ends of the crack inducing upper plate 4 are respectively detachably connected to the oblique connecting plate 102, the crack inducing lower plate 5 is also a pair, respectively vertically set below the crack inducing upper plate 4, the two ends of the crack inducing lower plate 5 are respectively detachably connected to the vertical connecting plate 103; the crack inducing lower plate 5 is set parallel to the short baffle 2, and tension rods 7 are also inserted in the middle of the short baffle 2.

[0049] The test device has a simple structure, is easy to assemble and disassemble, is convenient to use, and can be repeatedly combined to form a rectangular space with basically the same size; concrete is poured in the test device, and a pair of crack inducing upper plates 4 are arranged to enable the concrete to produce cracks with uniform cross-sections at specific positions, and the test device can be reassembled into the original fixed mode. After the repair material test, the repair effect can be visually observed through the empty space after the original crack inducing upper plate 4 and the crack inducing lower plate 5 are disassembled. The operation is simple, the effect is easy to obtain, and it is suitable for the inspection of various repair materials.

[0050] The structure in which the long baffle plate 1 and the short baffle plate 2 are connected to the lower base plate 3 can be fixed by bolts. Corresponding screw holes are provided on each plate. The screw holes on each side can be directly screwed in after they correspond to each other. No other positioning and fixing parts are required. The structure can be disassembled and repeatedly connected for use, and the degree of restoration is high.

[0051] The guide plate mounting hole 101 is arranged in the middle of the longitudinal baffle 1, so that the guide plates can be arranged in the middle, so that the fracture site of the concrete specimen is in the middle, which has a better guiding and position selection effect. The crack induction lower plate 5 and the crack induction upper plate 4 are respectively arranged as a pair of independent ones, which are convenient for sequential installation and removal without interfering with each other. They can be installed according to the shape and position of the guide plate mounting hole 101, and can be directly pulled out when removed.

[0052] The inclined connecting plate 102 and the vertical connecting plate 103 are respectively used to connect and fix the crack induction upper plate 4 and the crack induction lower plate 5, and have the functions of guiding and positioning.

[0053] The tension rods 7 are inserted horizontally and vertically on the short-side baffle 2, so that both ends of the formed concrete specimen are provided with the tension rods 7, which is convenient for direct pulling on the testing machine; moreover, such a setting will not affect the removal of the short-side baffle.

[0054] When pouring concrete, the main parts of the crack induction upper plate 4 and the crack induction lower plate 5 are both installed in the rectangular space. In this way, a uniform point-inverted V-shaped groove is formed under the formed concrete specimen, which is beneficial to the generation of cracks in the concrete specimen during pulling, reduces damage at other positions, and also avoids the falling of irregular soil blocks so as to avoid difficult splicing and restoration; during the crack repair material test, after the rectangular space is assembled, the crack induction upper plate and the lower plate do not need to be installed, and the empty space here is convenient for observing the leakage situation.

[0055] Furthermore, first wing plates 104 are respectively provided on both sides and the bottom of the long-side baffle 1. The first wing plates 104 on both sides are respectively screwed and fixed to both sides of the short-side baffle 2, and the first wing plate 104 at the bottom is screwed and fixed to the lower bottom plate 3. The first wing plates 104 at the bottom all extend to the vertical connecting plate 103 and are connected together.

[0056] The first wing plates 104 are all arranged on the outside, which is convenient for docking and installation. Moreover, the first wing plates 104 at the bottom can increase the bottom support area of the long-side baffle 1, so that it can stand vertically on the lower bottom plate 3, which is convenient for subsequent bolt fixed connection.

[0057] The first wing plates 104, the inclined connecting plate 102, the vertical connecting plate 103 and the long-side baffle are of an integrally formed structure, and such a structure has high stability and is durable.

[0058] Furthermore, second wing plates 201 are respectively provided at the bottom of the short-side baffle 2. The second wing plates 201 are respectively screwed and fixed to the lower bottom plate 3, and the length of the short-side baffle 2 is the same as the width of the lower bottom plate 3.

[0059] The second wing plates 201 are also of an integral structure with the short-side baffle 2. The arrangement of the second wing plates 201 is also convenient for the installation of the short-side baffle 2, and the bolt connection positions are all arranged on the outside, which is convenient for operation.

[0060] Further, an opening 202 is provided in the middle of the short-side baffle 2, the tension rod 7 is inserted into the opening 202, and the diameter of the opening 202 is larger than the outer diameter of the tension rod 7. Such a setting facilitates the insertion of the tension rod 7 and also facilitates the removal of the short-side baffle 2.

[0061] Further, the included angle between a pair of the crack-inducing upper plates 4 is 90 degrees, and the docking intersection line of the pair of the crack-inducing upper plates 4 is located at the exact middle of the rectangular space. Such a setting of the angle and position can induce the crack to break in the middle, and the symmetrical setting on both sides makes the stress more balanced, which is beneficial to the formation of regular cracks.

[0062] Further, the bottom of the induction plate mounting hole 101 is open, and the vertex position of the induction plate mounting hole 101 is located at 80% of the vertical height of the long-side baffle 1. This can ensure a certain thickness at the crack induction location without being too large.

[0063] Further, the crack-inducing lower plate 5 and the crack-inducing upper plate 4 have the same length, and both are longer than the length of the short-side baffle 2; both ends of the crack-inducing lower plate 5 and the crack-inducing upper plate 4 extend beyond the inclined connecting plate 102.

[0064] Such a setting can ensure that both ends of the crack-inducing upper plate 4 are exposed for subsequent disassembly; the crack-inducing lower plate 5 can support the crack-inducing upper plate 4, and at the same time, together with the crack-inducing upper plate 4, make the interior of the rectangular space a closed structure, so that it can be used to fill concrete.

[0065] Further, as Figure 5 and Figure 6 shown, the cross-section of the crack-inducing upper plate 4 is an isosceles trapezoid, the lower base angle of the isosceles trapezoid is 45 degrees, and the length of the lower base of the isosceles trapezoid is the same as the length of the hypotenuse of the induction plate mounting hole 101. Such a crack-inducing upper plate 4 has a certain thickness and guaranteed strength. Setting its cross-sectional shape as an isosceles trapezoid facilitates the formation of the included angle and can also be closely matched with the induction plate mounting hole 101 and the inclined connecting plate 102.

[0066] Further, as Figure 7 shown, the cross-section of the crack-inducing lower plate 5 is rectangular, and the side length of the rectangle is the same as the length of the vertical side of the induction plate mounting hole 101.

[0067] Embodiment 2:

[0068] A test method for the concrete crack repair performance, the test method comprising the following steps:

[0069] Step 1: Use bolts 6 to fixedly connect the long baffle 1 with the lower bottom plate 3, the short baffle 2 with the lower bottom plate 3, and the long baffle 1 with the short baffle 2 to form a rectangular space with an upper opening;

[0070] Step 2: Insert the crack induction upper plate 4 and the crack induction lower plate 5 into the induction plate mounting holes 101 in sequence, penetrate a pair of the long baffles 1, adjust the included angle between a pair of the crack induction upper plates 4 to 90 degrees and fix them with bolts 6;

[0071] Step 3: Insert the tension rods 7 into the short baffles 2 respectively and fix the tension rods 7 on the outside; Apply a coating agent in the connected test device, pour concrete with a specified mix ratio, and cure it under standard conditions;

[0072] Step 4: After curing, loosen all the connected bolts 6, take out the crack induction upper plate 4 and the crack induction lower plate 5 in sequence, and remove the short baffle 2 and the long baffle 1 to obtain a concrete specimen with tension rods at both ends;

[0073] Step 5: Place the concrete specimen in step 4 on a concrete testing machine, that is, fix the tension rods on the concrete specimen on the concrete testing machine and break the concrete specimen;

[0074] Step 6: Reassemble and fix the broken concrete specimen in the test device, that is, fix the short baffle 2 with the lower bottom plate 3, the short baffle 2 with the long baffle 1, and the long baffle 1 with the lower bottom plate 3 respectively, so that the broken and spliced concrete specimen returns to the fixed mode before the test;

[0075] Step 7: Spray a crack repair material on the cracks of the concrete specimen after it is broken and cured;

[0076] Step 8: After reaching the time specified for the construction of the repair material, pour water on the cracks and observe whether there is water seepage under the position of the original crack induction upper plate. If there is no water seepage and wet stains, it indicates the effectiveness of the crack repair material.

[0077] Through the operation of the test method, a concrete specimen with a relatively stable crack fracture surface can be obtained. In this way, when conducting the crack repair material performance test, the error is small, the influence on the test results is small, and the same test device can be used for the forming of the concrete specimen and the observation of crack penetration.

[0078] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An experimental device for the repair performance of concrete cracks, including a lower bottom plate, characterized in that, A pair of long baffles are symmetrically arranged on the lower bottom plate along the length direction, and a pair of short baffles are symmetrically arranged on the lower bottom plate along the width direction. The long baffles, the short baffles and the lower bottom plate are detachably connected together to form a rectangular space with an upper opening. An induction plate mounting hole with a triangle on the upper part and a rectangle on the lower part is arranged in the middle of the long baffle. A pair of inclined connecting plates and a pair of vertical connecting plates are arranged outside the induction plate mounting hole. The pair of inclined connecting plates are arranged along the hypotenuse of the triangle, and the vertical connecting plates are arranged along the opposite sides of the rectangle and are arranged below the inclined connecting plates. A crack induction upper plate and a crack induction lower plate spanning the rectangular space are inserted into the pair of induction plate mounting holes. The crack induction upper plates are in pairs and are spliced into an inverted "V" shape structure. The two ends of the crack induction upper plate are respectively detachably connected to the inclined connecting plates. The crack induction lower plates are also in pairs and are respectively vertically arranged below the crack induction upper plates. The two ends of the crack induction lower plate are respectively detachably connected to the vertical connecting plates. The crack induction lower plate is arranged parallel to the short baffle, and a tension rod is respectively inserted into the middle of the short baffle. In the test device, the concrete specimen after fracture splicing is restored to the fixed mode before the test. After the repair material test, the repair effect can be directly observed through the vacant positions after the disassembly of the original crack induction upper plate and the crack induction lower plate. First wing plates are respectively arranged on both sides and the bottom of the long baffle. The first wing plates on both sides are respectively screwed and fixed to both sides of the short baffle, and the first wing plate at the bottom is screwed and fixed to the lower bottom plate. The first wing plates at the bottom both extend to the vertical connecting plates and are connected together. Second wing plates are respectively arranged at the bottom of the short baffle. The second wing plates are respectively screwed and fixed to the lower bottom plate, and the length of the short baffle is greater than the distance between the pair of long baffles.

2. The test device for the performance of concrete crack repair according to claim 1, characterized in that, An opening is arranged in the middle of the short baffle, and the tension rod is inserted into the opening. The aperture of the opening is greater than the outer diameter of the tension rod.

3. The test device for the performance of concrete crack repair according to claim 1, characterized in that The included angle between the pair of crack induction upper plates is 90 degrees, and the docking intersection line of the pair of crack induction upper plates is located at the exact middle of the rectangular space.

4. The test device for the concrete crack repair performance according to claim 1, characterized in that, The bottom of the induction plate mounting hole is open, and the vertex position of the induction plate mounting hole is located at 50%-90% of the vertical height of the long baffle.

5. The test device for the concrete crack repair performance according to claim 1, characterized in that, The crack induction lower plate and the crack induction upper plate have the same length, and both are longer than the length of the short baffle. Both ends of the crack induction lower plate and the crack induction upper plate extend out of the inclined connecting plates.

6. The test device for the performance of concrete crack repair according to claim 1, characterized in that, The cross section of the crack induction upper plate is an isosceles trapezoid, the lower bottom angle of the isosceles trapezoid is 45 degrees, and the length of the lower bottom side of the isosceles trapezoid is the same as the length of the hypotenuse of the induction plate mounting hole.

7. The test device for the concrete crack repair performance according to claim 1, characterized in that, The cross section of the crack induction lower plate is a rectangle, and the side lengths of the rectangle are the same as the lengths of the vertical sides of the induction plate mounting hole.

8. A test method for a test device for the performance of concrete crack repair as described in claim 1, characterized in that, The test method includes the following steps: Step 1: Use bolts to fixedly connect the long baffle with the lower bottom plate, the short baffle with the lower bottom plate, and the long baffle with the short baffle to form a rectangular space with an upper opening. Step 2: Insert the crack-induced upper plate and the crack-induced lower plate into the induced plate mounting holes in sequence, penetrate a pair of the long-side baffles, adjust the included angle between the pair of crack-induced upper plates to 90 degrees and fix them with bolts; Step 3: Insert the tension rods into the short-side baffles respectively and fix the tension rods on the outside; apply a coating agent in the connected test device, pour concrete with a specified mix ratio, and cure it under standard conditions; Step 4: After curing, loosen all the connected bolts, take out the crack-induced upper plate and the crack-induced lower plate in sequence, and remove the short-side baffles and the long-side baffles to obtain a concrete specimen with tension rods at both ends; Step 5: Place the concrete specimen in Step 4 on a concrete testing machine, that is, fix the tension rods on the concrete specimen on the concrete testing machine and break the concrete specimen; Step 6: Reassemble and fix the broken concrete specimen in the test device, that is, fix between the short-side baffle and the lower bottom plate, between the short-side baffle and the long-side baffle, between the long-side baffle and the lower bottom plate, and between the tension rod and the short-side baffle respectively, so that the broken and spliced concrete specimen returns to the fixed mode before the test; Step 7: Spray or apply a crack repair material on the crack of the broken concrete specimen and cure it; Step 8: After reaching the time specified for the construction of the repair material, pour water on the crack and observe whether there is water seepage under the position of the original crack-induced upper plate. If there is no water seepage and wet stains, it indicates the effectiveness of the crack repair material.

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