A material, device and method for repairing concrete cracks based on biomimetic mineralization by grouting

Abstract

The application discloses a kind of based on biomimetic mineralization grouting repair concrete crack material, device and method, the material of the present application contains organic matrix, belongs to biomimetic mineralization, the present application provides two kinds of grouting repair concrete crack material, can form calcium carbonate by chemical mineralization or microbiological mineralization mode, the two kinds of grouting repair concrete crack material provided by the present application are low viscosity repair agent, good fluidity, it is favorable to realize the repair of crack deep place, easy to inject narrow crack.The repair material formed by the present application is calcium carbonate precipitation containing organic matrix, belongs to inorganic salt, and is not easy to age, green and environmental protection.The device of the present application only needs to design corresponding hole on different functional areas of soft suction disc, the suction disc is firmly adsorbed on the surface of concrete by the communication hole of adsorption area, then the repair material designed by the present application is injected through grouting hole, i.e., the biomimetic device and biomimetic mineralization repair agent can be combined, to achieve the effect of green and efficient crack repair.

Description

Technical Field

[0001] This invention belongs to the field of concrete structure repair technology, and more specifically, relates to a material, device and method for repairing concrete cracks by grouting based on biomimetic mineralization. Background Technology

[0002] Currently, concrete has long been the main material in various engineering fields. However, its tensile strength is insufficient, and under the influence of harsh external environments, it inevitably develops cracks, providing channels for the intrusion of external moisture, chloride ions, and oxygen. This accelerates the deterioration process such as steel corrosion and concrete carbonation, reducing the safety and durability of building structures, leading to a decrease in the load-bearing capacity of the structure, and in severe cases, even causing casualties and economic losses.

[0003] When concrete cracks, repair materials are needed. Traditional repair materials, such as epoxy resin and polyurethane grouting materials, have problems such as easy aging and environmental toxicity. In addition, traditional repair materials are high-viscosity materials, which are difficult to penetrate deep into cracks and difficult to inject into narrow cracks.

[0004] It is evident that existing technologies for repairing concrete cracks suffer from technical problems such as easy aging, environmental toxicity, difficulty in penetrating deep into cracks, and difficulty in injecting into narrow cracks. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of existing technologies, the present invention provides a material, device and method for grouting repair of concrete cracks based on biomimetic mineralization, thereby solving the technical problems of existing concrete crack repair technologies, such as easy aging, environmental toxicity, difficulty in penetrating deep into cracks and difficulty in injecting into narrow cracks.

[0006] To achieve the above objectives, according to a first aspect of the present invention, a material for grouting repair of concrete cracks based on biomimetic mineralization is provided, comprising: solution A and solution B, wherein when the material is applied to repair concrete cracks, solution A and solution B are injected alternately.

[0007] Solution A consists of 0.2 mol / L to 1.0 mol / L calcium salt and 1 g / L to 3 g / L environmentally friendly polymer containing polar functional groups that can attract calcium carbonate; solution B consists of 0.2 mol / L to 1.0 mol / L carbonate.

[0008] Furthermore, the polymer is carboxylated chitosan, polyaspartic acid, alginate, or vegan gum; the calcium salt is calcium chloride, calcium acetate, calcium nitrate, heavy calcium carbonate, or calcium lactate; and the carbonate is sodium carbonate, lithium carbonate, or potassium carbonate.

[0009] To achieve the above objectives, according to a second aspect of the present invention, a material for grouting and repairing concrete cracks based on biomimetic mineralization is provided, comprising: solution A and solution B, wherein when the material is applied to repair concrete cracks, solution A and solution B are simultaneously injected into the grout.

[0010] Solution A consists of 0.2 mol / L to 1.0 mol / L calcium salt, 0.2 mol / L to 1.0 mol / L urea, and 1 g / L to 3 g / L of an environmentally friendly polymer containing polar functional groups that can attract calcium carbonate. Solution B consists of a suspension of urease bacteria at 107 CFU / mL to 108 CFU / mL.

[0011] Further, the polymer is carboxylated chitosan, polyaspartic acid, alginate, or vegan gum; the calcium salt is calcium chloride, calcium acetate, calcium nitrate, heavy calcium carbonate, or calcium lactate; and the urease suspension is a suspension of Bacillus pasteurellii, Bacillus subtilis, Bacillus megaterium, Bacillus pseudosturcium, or Bacillus coli.

[0012] To achieve the above objectives, according to a third aspect of the present invention, a device for grouting and repairing concrete cracks based on biomimetic mineralization is provided, comprising a soft suction cup, the lower surface of which is divided into an adsorption area and a crack grouting area. The adsorption area has N connecting holes extending from the upper surface to the lower surface of the soft suction cup, for connecting a vacuum pump via a vacuum tube when the device repairs concrete cracks. The crack grouting area has M grouting holes extending from the upper surface to the lower surface of the soft suction cup, for connecting a grouting pipe when the device repairs concrete cracks. The material injected into the grouting pipe is a biomimetic mineralization-based material for grouting and repairing concrete cracks, wherein N≥1 and M≥1.

[0013] Furthermore, the grouting area of ​​the crack is in the middle of the lower surface of the soft suction cup, and the adsorption area is on both sides of the grouting area. This is conducive to firmly attaching the soft suction cup to the concrete surface to be repaired by vacuuming the adsorption area. Especially when the concrete to be repaired is a curved surface, this arrangement can be used to vacuum and adsorb from both sides, which can ensure that the soft suction cup is quickly and firmly attached to the curved surface.

[0014] Furthermore, the crack grouting area is a strip-shaped groove that completely covers the concrete crack below the crack grouting area. Preferably, the strip-shaped groove just covers the concrete crack below the crack grouting area, which achieves the best effect and lowest cost.

[0015] Furthermore, the material of the soft suction cup is silicone rubber, polyurethane, or neoprene rubber.

[0016] To achieve the above objectives, according to a fourth aspect of the present invention, a method for repairing concrete cracks by grouting based on biomimetic mineralization is provided, comprising:

[0017] A biomimetic mineralization-based grouting device for repairing concrete cracks is designed at both ends of a concrete crack. The grouting holes are aligned with the concrete crack to seal the crack between the two ends of the device.

[0018] The connecting hole is connected to a vacuum pump through a vacuum tube. The vacuum pump is used to create a vacuum and fix the soft suction cup to both ends of the concrete crack to be repaired.

[0019] A biomimetic mineralization-based grouting material is injected into the concrete crack through the grouting hole on the soft suction cup at one end of the crack, while the grouting hole on the soft suction cup at the other end of the crack is used to collect waste liquid until the concrete crack is completely sealed.

[0020] Furthermore, the method also includes:

[0021] Before injecting the material into the grouting hole, the grouting hole is connected to a vacuum pump through a vacuum tube. The vacuum pump is used to extract air to remove impurities from the concrete crack. After the impurities in the concrete crack are removed, the vacuum tube is removed. Water is injected into the grouting hole on the soft suction cup at one end of the concrete crack until the inside of the concrete crack is completely wetted. Then, a material based on biomimetic mineralization for grouting and repairing concrete cracks is injected into the grouting hole.

[0022] To achieve the above objectives, according to a fifth aspect of the present invention, a method for repairing concrete cracks by grouting based on biomimetic mineralization is provided, comprising:

[0023] A biomimetic mineralization-based grouting device for repairing concrete cracks is arranged in the middle and at both ends of the cracks. The grouting holes are aligned with the concrete cracks to seal the surface of the cracks between adjacent devices.

[0024] The connecting hole is connected to a vacuum pump through a vacuum tube. The vacuum pump is used to create a vacuum and fix the soft suction cup to the surface of the concrete crack to be repaired.

[0025] A biomimetic mineralization-based grouting material is injected into the concrete crack through the grouting holes on the soft suction cups in the middle of the crack. The grouting holes on the soft suction cups at both ends of the crack are used to collect waste liquid until the concrete crack is completely sealed.

[0026] Furthermore, the specific methods for surface sealing are as follows: applying waterproof tape tightly to the center of the crack, or uniformly applying thermoplastic dressing to the surface of the crack.

[0027] Furthermore, before deploying a biomimetic mineralization-based grouting device for repairing concrete cracks on the surface of the cracks, the area to be repaired in the concrete cracks is ground to make its surface smooth, and then the surface is cleaned to remove dust and impurities.

[0028] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0029] (1) The formula of this invention contains an organic matrix, which belongs to biomimetic mineralization controlled by a soft template. The formula of this invention contains calcium salt, a polymer containing polar functional groups that is harmless to the environment and can attract calcium carbonate, and carbonate. Carbonate precipitation can be induced by biomimetic methods, which belongs to the process of inducing the formation of organic matrix-inorganic mineral composite minerals using an organic matrix. Compared with simple microbial repair, biomimetic mineralization has the advantages of excellent mechanical properties, fast reaction rate, and thorough reaction, which can ensure the repair effect of concrete cracks. The material composition and concentration of this invention determine that the repair material of this invention is a low viscosity material. The low viscosity repair agent used in this invention has good fluidity, which is conducive to the repair of deep cracks and easy to inject into narrow cracks. The repair material formed by this invention is calcium carbonate precipitate containing an organic matrix, which belongs to inorganic salt, is not easy to age, and is green and environmentally friendly. When the formula is calcium salt, polymer and carbonate, the calcium carbonate precipitation originates from a chemical mineralization reaction. The reaction is too fast. If solution A and solution B are injected at the same time, the chemical reaction will occur first during injection, which will not play a repair role. Alternating injection of solution A and solution B can effectively control the reaction rate and ensure the repair effect. After treating concrete cracks with the repair material of this invention, XRD tests were performed on the minerals formed at the cracks. The results showed that the minerals formed after the repair were mainly composed of aragonite, which is a metastable calcium carbonate crystal form that can adhere well to the cracks, ensuring the repair effect and thus improving the safety and durability of the building structure.

[0030] (2) The polymers selected in this invention have many advantages, including being environmentally friendly, having abundant polar functional groups, and being able to attract calcium carbonate. Carboxylated chitosan, polyaspartic acid, and alginate have abundant carboxylic acid groups, while vegan gum has hydroxyl and carboxylic acid groups. In contrast, Chinese invention patent CN114349404A discloses a method for biomimetic mineralization cementing of loose sand particles. This method uses aspartic acid as an organic matrix for biomimetic mineralization to regulate crystal growth. However, aspartic acid has very few sites (carboxyl and amino groups) that can bind to calcium carbonate, requiring a high dosage equivalent to that of calcium ions and carbonate ions, resulting in extremely high costs and insignificant effects, making it unsuitable for engineering applications. Furthermore, high dosages of organic components increase the viscosity of the repair agent and limit the adhesive strength of the product. Small molecule additives require large quantities and are extremely expensive. This invention uses organic polymers rich in strong polar functional groups such as carboxyl and hydroxyl groups as raw materials for biomimetic mineralization repair agents, which can greatly reduce application costs. Simultaneously, the chain-like carbon skeleton of the polymer can effectively improve the mechanical properties of the biomimetic mineralization repair agent.

[0031] (3) The material of this invention belongs to the category of biomimetic mineralization remediation agents. It can mimic the mineralization behavior of microorganisms and synthesize inorganic materials with special structures and excellent physicochemical properties by controlling crystal growth. The components of this invention include calcium salts, urea, polymers, and urease-producing bacterial suspensions. The urease produced by the bacteria decomposes urea, forming carbonate ions that combine with calcium salts. The calcium carbonate formed at this time is microbial mineralization and belongs to the category of enhanced biomineralization remediation agents. Single biomimetic mineralization methods lack the regulatory effect of microorganisms and are often less effective than microbial mineralization (MICP) technology. The enhanced biomineralization remediation agent used in this invention can organically integrate the advantages of biomimetic mineralization methods and MIP technology. When using the enhanced biomineralization remediation agent, solutions A and B are injected simultaneously. At this time, solutions A and B are not suitable for alternating injection because the reaction process of microbial decomposition of urea is slow enough, and alternation would result in waste of raw materials. The enhanced biomineralization remediation agent designed in this invention has low viscosity, making it easy to penetrate deep into cracks and also suitable for injection into narrow cracks. The main component is carbonate minerals, which do not age and do not pollute the environment.

[0032] (4) Cracks in underground engineering projects (such as tunnels) are often located on curved concrete surfaces, making it difficult for conventional repair devices to adhere to them. The device of this invention is a soft suction cup, which can be used to flexibly adhere to cracks on curved concrete walls, offering a simple and tight fit. This invention only requires designing corresponding holes in different functional areas of the soft suction cup. By drawing air through the connecting holes in the adsorption area to create negative pressure, the suction cup is firmly adsorbed onto the concrete surface. Then, the repair material designed in this invention is injected through the grouting holes, thus combining the biomimetic device with the biomimetic mineralization repair agent to achieve a green and efficient crack repair effect.

[0033] (5) In existing technologies CN 104295110B, CN 109083435B, and CN 116856750A, the grouting ports are all point-type grouting, which can only repair wide cracks. For the most common fine cracks, the grouting ports are too small, making the grouting process very time-consuming. In this invention, the crack grouting area is a strip-shaped groove. The repair agent injected into the grouting hole forms a strip-shaped repair agent that moves in the crack. The soft suction cup and the grouting port are integrated into one structure, which can realize strip-shaped grouting. The strip-shaped grouting method of this invention allows the repair agent to slowly mineralize inside the crack, which is conducive to achieving complete sealing. Moreover, the larger grouting surface is more conducive to controlling a stable grouting flow rate. The strip-shaped groove completely covers the concrete crack below the crack grouting area, which can ensure the repair effect of the crack.

[0034] (6) The soft suction cup of the present invention can be made of silicone rubber with good fit, wide temperature range and excellent anti-aging properties, or high hardness polyurethane with high wear resistance, high mechanical strength and corrosion resistance, or low cost, moisture resistance and wear resistance neoprene rubber with certain deformation ability, which can fit curved side walls and is suitable for non-planar concrete walls.

[0035] (7) When the concrete crack is of moderate length, a grouting repair device based on biomimetic mineralization, as designed in this invention, is arranged at both ends of the concrete crack. Grout is injected at one end, and waste liquid is collected at the other end. The method of grouting at one end and collecting at the other end used in this invention can achieve both slag removal and full impregnation (venting) within the crack, as well as the recovery of unreacted raw materials. When the concrete crack is long, a grouting repair device based on biomimetic mineralization is arranged at the middle and both ends of the concrete crack. Grout is injected in the middle, and waste liquid is discharged at both ends, which improves repair efficiency while ensuring repair effect. The two repair methods provided by this invention enable the device of this invention to be used for concrete cracks of various lengths.

[0036] (8) Based on the idea that leeches secrete anticoagulants when they suck blood onto the host's skin, this invention uses blood sucking as a way to remove impurities from cracks and the anticoagulant as a repair material. Without altering the device structure, the injection holes are given multiple uses. Without venting, calcium carbonate deposition creates cavities inside the cracks, resulting in a loose structure and affecting the repair effect. In this invention, both venting and wetting are accomplished by injecting water; wetting allows the solution to penetrate deeper into the cracks. This invention only requires attaching the device to the concrete surface, removing slag, venting, and wetting, after which the biomimetic mineralization repair agent can be injected. This is convenient, efficient, and reduces labor costs. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a device for repairing concrete cracks based on biomimetic mineralization through grouting, provided in an embodiment of the present invention.

[0038] Figure 2 This is a schematic diagram of the lower surface of the soft suction cup provided in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the flow path of the low-viscosity biomimetic mineralization repair agent in the crack profile provided in the embodiments of the present invention;

[0040] Figure 4 This is an XRD pattern of the minerals formed after the biomimetic mineralization repair agent provided in this embodiment of the invention repairs cracks;

[0041] Figure 5 This is a SEM image of the minerals formed after the biomimetic mineralization repair agent provided in Embodiment 1 of the present invention repairs cracks;

[0042] Figure 6 This is a SEM image of the minerals formed after the biomimetic mineralization repair agent provided in Embodiment 2 of the present invention repairs cracks;

[0043] Figure 7This is a SEM image of the minerals formed after the biomimetic mineralization repair agent provided in Embodiment 3 of the present invention repairs cracks;

[0044] Figure 8 This is a SEM image of the mineralized material formed after the biomimetic mineralization repair agent provided in Embodiment 4 of the present invention repairs cracks.

[0045] Figure 9 This is a SEM image of the mineralized material formed after the biomimetic mineralization repair agent provided in Embodiment 5 of the present invention repairs cracks.

[0046] Figure 10 This is the energy spectrum of the minerals formed after the biomimetic mineralization repair agent provided in Example 4 of this invention repairs cracks;

[0047] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0048] 1 is a soft suction cup, 2 is a grouting port, 3 is a vacuum port, 4 is the outer surface of the concrete crack, 5 is waterproof tape or thermoplastic dressing, 6 is a waste liquid collection port, 7 is the adsorption area, 8 is the crack grouting area, and 9 is the crack profile. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0050] Existing crack repair methods generally include surface coating and grouting. While numerous crack detection devices exist, crack repair devices are lacking. The efficiency and repair quality of current crack repair devices are difficult to guarantee. Existing technologies use point-type grouting ports, which can only repair wide cracks. For the most common fine cracks, the grouting ports are too small, making the grouting process very time-consuming. This invention only requires designing corresponding holes in different functional areas of the soft suction cup. The suction cup can be firmly adhered to the concrete surface through the connecting holes in the adsorption area. Then, the repair material designed in this invention is injected through the grouting holes, combining a biomimetic device and a biomimetic mineralization repair agent to achieve a green and efficient crack repair effect.

[0051] This invention provides a device for repairing concrete cracks using biomimetic mineralization-based grouting. The device includes a soft suction cup, the lower surface of which is divided into an adsorption area and a grouting area. The adsorption area has N connecting holes extending from the upper to the lower surface of the suction cup, used to connect a vacuum pump via a vacuum tube during concrete crack repair. The grouting area has M grouting holes extending from the upper to the lower surface of the suction cup, used to connect grouting pipes during crack repair. The material injected into the grouting pipes is a biomimetic mineralization-based grouting material for repairing concrete cracks, where N is a positive integer greater than or equal to 1, and M is a positive integer greater than or equal to 1. The combination of the device within the range of values ​​designed in this invention and the repair agent designed in this invention can solve the problems of efficiency and difficulty in guaranteeing repair quality in crack repair devices.

[0052] This invention's device can be used for concrete cracks of various lengths. When the crack length is moderate, the device, based on biomimetic mineralization, is arranged at both ends of the crack, with grouting at one end and waste liquid collected at the other. When the crack is long, the device is arranged in the middle and at both ends, with grouting in the middle and waste liquid discharged at both ends, improving repair efficiency while ensuring repair effectiveness.

[0053] like Figure 1 As shown, this invention provides a device for repairing cracks of moderate length while controlling costs and ensuring efficiency in a specific embodiment. In this case, M=1, N=2, the hole at the grouting end is called the grouting hole, and the hole at the waste liquid collection end is called the waste liquid collection port. The device includes: a soft suction cup 1, one soft suction cup with a grouting port 2 and two vacuum ports 3, and another soft suction cup with a waste liquid collection port 6 and two vacuum ports 3. The crack between the two soft suction cups is the outer surface 4 of the concrete crack. Waterproof tape (or thermoplastic dressing) 5 is tightly adhered to the outer surface 4 of the concrete crack.

[0054] like Figure 2 As shown, the crack grouting area 8 is located in the center of the lower surface of the soft suction cup, and the adsorption areas 7 are located on both sides of the crack grouting area. This arrangement facilitates the vacuuming of the adsorption areas to firmly adhere the soft suction cup to the concrete surface to be repaired. Especially when the concrete to be repaired is a curved surface, this arrangement allows for vacuuming and adsorption from both sides, ensuring a rapid and secure fit between the soft suction cup and the curved surface. The crack grouting area is a strip-shaped groove that completely covers the concrete crack below the crack grouting area.

[0055] like Figure 3 As shown, the repair agent is injected from the grouting port 2 and flows in the crack profile 9 on the lower surface of the waterproof tape (or thermoplastic dressing) 5, while the waste liquid flows out from the waste liquid collection port 6.

[0056] All of the above are used in embodiments 1-5 of this invention. Figure 1 The device described herein is described, but those skilled in the art will know after reading this invention that the form and arrangement of the device are diverse in specific implementations.

[0057] Example 1

[0058] A method for repairing concrete cracks using grouting based on biomimetic mineralization, taking the repair of the curved inner wall of tunnel concrete as an example, includes the following steps:

[0059] Step S1: Prepare a two-component biomimetic mineralization repair agent. Solution A contains 0.5 mol / L calcium chloride and 2 g / L carboxylated chitosan, and solution B contains 0.5 mol / L sodium carbonate.

[0060] Step S2: Grind the area to be repaired to make its surface smooth, then clean the surface to remove dust and impurities, and blow ultrafine quartz sand into the crack.

[0061] Step S3: Seal the surface of the concrete crack with waterproof tape or thermoplastic dressing, leaving two ends for grouting and waste liquid collection, respectively.

[0062] Step S4: Device Fitting and Fixing. Align the grouting area at the bottom of the silicone rubber soft suction cup of the device with one end of the concrete crack, and let the adsorption areas span both sides of the concrete crack, so that it fits against the cracked concrete surface. Connect the vacuum tube to the vacuum pump, and fix the two sets of the device of the present invention to the two ends of the crack on the concrete surface respectively.

[0063] Step S5: Remove impurities from the crack. Use the grouting port (or waste liquid collection port) of the device of the present invention to draw air out the impurities in the crack, then use another waste liquid collection port (or grouting port) to draw air again to fully remove the impurities in the crack.

[0064] Step S6: Venting and Soaking. Using the grouting port of the device of the present invention, clean water is continuously injected into the crack until the crack is completely soaked.

[0065] Step S7: Using the device of the present invention, grouting is performed by alternately injecting solution A and solution B into one end of the crack (grouting port), and waste liquid is collected at the other end (waste liquid collection port) until the crack is completely sealed.

[0066] Example 2

[0067] A method for repairing concrete cracks using biomimetic mineralization-based grouting includes the following steps:

[0068] Step S1: Prepare the enhanced biomineralization repair agent. First, prepare the bacterial culture, which needs to be cultured one day in advance to ensure activity. Second, prepare the two-component repair agent, wherein solution A contains 0.5 mol / L calcium chloride, 0.5 mol / L urea, and 2 g / L carboxylated chitosan, and solution B has a bacterial concentration of 8 × 10⁻⁶. 7 CFU / mL of Bacillus pasteurellium suspension.

[0069] Step S2: Grind the area around the area to be repaired to make the surface smooth, then clean the surface to remove dust and impurities, and blow ultrafine quartz sand into the crack.

[0070] Step S3: Seal the surface of the concrete crack with waterproof tape or thermoplastic dressing, leaving two ends for grouting and waste liquid collection, respectively.

[0071] Step S4: Device Fitting and Fixing. Align the grouting area at the bottom of the silicone rubber soft suction cup of the device with one end of the concrete crack, and let the adsorption areas span both sides of the crack, so that it fits against the cracked concrete surface. Connect the vacuum tube to the vacuum pump and fix the two sets of the device of the present invention to the concrete surface.

[0072] Step S5: Remove impurities from the crack. Use the grouting port (or waste liquid collection port) of the device of the present invention to draw air out the impurities in the crack, then use another waste liquid collection port (or grouting port) to draw air again to fully remove the impurities in the crack.

[0073] Step S6: Venting and Soaking. Using the grouting port of the device of the present invention, clean water is continuously injected into the crack until the crack is completely soaked.

[0074] Step S7: Finally, using the device of the present invention, solution A and solution B are simultaneously injected into the concrete crack from one end of the crack (grouting port), and waste liquid is collected from the other end of the crack (waste liquid collection port) until the crack is completely sealed.

[0075] Example 3

[0076] Example 3 is identical to Example 2 except for the type of polymer used. The polymer used in Example 3 is 2 g / L polyaspartic acid.

[0077] Example 4

[0078] Example 4 is identical to Example 2 except for the type of polymer used. The polymer used in Example 4 is 2 g / L alginate.

[0079] Example 5

[0080] Example 5 is identical to Example 2 except for the type of polymer used. The polymer used in Example 5 is 2 g / L of Weyland gum (Brunei gum).

[0081] Blank control group

[0082] The blank control group, compared to Example 2, did not have any organic matrix (polymer) added.

[0083] The biomimetic mineralization repair agent used in Example 1 corresponds to a repair material that forms calcium carbonate through chemical mineralization. For repair materials that form calcium carbonate through chemical mineralization, in addition to the formulation provided in Example 1, the concentration of calcium chloride can be 0.2 mol / L or 1.0 mol / L. Calcium chloride can also be replaced by calcium acetate, calcium nitrate, heavy calcium carbonate, or calcium lactate. The concentration of carboxylated chitosan can also be 1 g / L or 3 g / L. The concentration of sodium carbonate can also be 0.2 mol / L or 1.0 mol / L, and sodium carbonate can also be replaced by lithium carbonate or potassium carbonate.

[0084] The biomimetic mineralization remediation agent used in Example 2 corresponds to a remediation material that forms calcium carbonate through microbial mineralization. For remediation materials that form calcium carbonate through microbial mineralization, in addition to the formulation provided in Example 2, the concentration of calcium chloride can be 0.2 mol / L or 1.0 mol / L. Calcium chloride can also be replaced by calcium acetate, calcium nitrate, heavy calcium carbonate, or calcium lactate. The concentration of carboxylated chitosan can also be 1 g / L or 3 g / L. The concentration of urea can be 0.2 mol / L or 1.0 mol / L. The concentration of Bacillus pasteurellium suspension can also be 10 g / L. 7 CFU / mL or 10 8 CFU / mL, Bacillus pasteurellium suspension can also be replaced by Bacillus subtilis suspension, Bacillus megaterium suspension, Bacillus pseudostrongylus suspension or Bacillus coli suspension.

[0085] The repair agents used in Examples 1 and 2 correspond to the two grouting materials for repairing concrete cracks provided by the present invention. Both are low-viscosity repair agents with good fluidity, which is conducive to repairing deep cracks and easy to inject into narrow cracks.

[0086] The soft suction cups used in Examples 1 and 2 are made of silicone rubber, which has good adhesion, a wide temperature range, and excellent anti-aging properties. In fact, the soft suction cup material of the present invention can also be high-hardness polyurethane with high wear resistance, high mechanical strength, and corrosion resistance, or low-cost, moisture-resistant, and wear-resistant neoprene rubber with a certain deformation capacity, which can fit curved sidewalls and is suitable for non-planar concrete walls.

[0087] XRD and SEM tests were performed on the mineralization formed at the repaired concrete cracks in Examples 1-5, and the results are as follows: Figure 4 (The blank control group, compared to Examples 2-5, did not contain any organic matrix.) Figure 5As shown.

[0088] After treating concrete cracks using the repair materials and methods provided in Examples 1-5 of this invention and the blank control group, XRD tests were performed on the minerals formed at the cracks. The results are as follows: Figure 4 As shown, the blank control group contained more calcite than aragonite, while Examples 1-5 mainly contained aragonite. This proves that the mineralized components formed after the repair by this invention are mainly aragonite, which is a metastable calcium carbonate crystal form that can adhere well to cracks, ensuring the repair effect and thereby improving the safety and durability of building structures.

[0089] Depend on Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 It is known that the organic matrix in the repair material used in this invention facilitates the biomimetic synthesis of the aragonite crystal form, forming a material microstructure with cross-linking effect, which can significantly enhance the compactness of the repair agent and achieve a good crack sealing effect. The polymer selected in this invention has many advantages such as being environmentally friendly, having abundant polar functional groups, and being able to attract calcium carbonate. Carboxylated chitosan, polyaspartic acid, and alginic acid have abundant carboxylic acid groups, and velan gum has hydroxyl and carboxylic acid groups.

[0090] In addition, such as Figure 10 As shown, the precipitate formed in Example 4 contains significant nitrogen (N) elements, indicating that the organic additive participated in the formation of the calcium carbonate binder, thus forming an organic matrix-inorganic mineral composite. Biomimetic mineralization repair agents mimic the mineralization behavior of microorganisms, synthesizing inorganic materials with special structures and excellent physicochemical properties by controlling crystal growth. The biomimetic induced carbonate precipitation formed in this invention is a process that utilizes an organic matrix to induce the formation of an organic matrix-inorganic mineral composite. Compared to simple microbial repair, biomimetic mineralization has the advantages of excellent mechanical properties, fast reaction rate, and thorough reaction. Combined with Examples 1-5, it can be seen that the combined application of the biomimetic device and biomimetic mineralization repair agent used in this invention has the ability to repair concrete cracks, achieving a green and efficient crack repair effect. Compared to the single microbial induced calcium carbonate deposition (MICP) technology, the organic matrix introduced in this invention can compensate for the deficiency of organic components (bacterial extracellular polymers), thereby effectively improving the toughness and strength of the product.

[0091] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for repairing cracks in concrete by grouting based on biomimetic mineralization, characterized in that, The device used in the method comprises a soft suction disc, the lower surface of the soft suction disc is divided into an adsorption area and a crack grouting area, the crack grouting area is a strip-shaped groove, and the strip-shaped groove completely covers the concrete cracks below the crack grouting area; The adsorption area is provided with N through holes penetrating from the upper surface to the lower surface of the soft suction disc, which are used to connect a vacuum pump through a vacuum pipe when the device repairs the concrete cracks, and the crack grouting area is provided with M grouting holes penetrating from the upper surface to the lower surface of the soft suction disc, which are used to connect a grouting pipe when the device repairs the concrete cracks, the material injected into the grouting pipe is a material for repairing the concrete cracks by grouting based on biomimetic mineralization, wherein N≥1 and M≥1, and the material comprises: an A solution and a B solution; When the material is applied to repair the concrete cracks, the A solution and the B solution are alternately grouted; The A solution is a calcium salt with a concentration of 0.2 mol / L-1.0 mol / L and a polymer with a concentration of 1 g / L-3 g / L, which is harmless to the environment, contains a polar functional group and can produce attraction to calcium carbonate, and the B solution is a carbonate salt with a concentration of 0.2 mol / L-1.0 mol / L; Alternatively, when the material is applied to repair the concrete cracks, the A solution and the B solution are simultaneously grouted; A solution of 0.2 mol / L to 1.0 mol / L calcium salt, 0.2 mol / L to 1.0 mol / L urea and 1 g / L to 3 g / L of an environmentally friendly polymer containing a polar functional group and capable of producing an attraction to calcium carbonate, B solution of 10 7 CFU / mL ~ 10 8 CFU / mL of urease bacteria suspension; The polymer is carboxymethyl chitosan, polyaspartic acid, alginic acid or welan gum, the calcium salt is calcium chloride, calcium acetate, calcium nitrate, heavy calcium carbonate or calcium lactate, and the carbonate salt is sodium carbonate, lithium carbonate or potassium carbonate; The method comprises: arranging the device at both ends of the concrete cracks, aligning the grouting holes with the concrete cracks, and performing surface sealing on the cracks between the devices at both ends; connecting the through holes to the vacuum pump through the vacuum pipe, and fixing the soft suction disc on the surface of the concrete cracks to be repaired by vacuumizing through the vacuum pump; injecting the material through the grouting hole on the soft suction disc at one end of the concrete cracks, and using the grouting hole on the soft suction disc at the other end of the concrete cracks to collect waste liquid until the concrete cracks are completely blocked.

2. A method of grouting repair of concrete cracks based on biomimetic mineralization as claimed in claim 1, wherein, The urease bacterial suspension is a Bacillus pasteurii suspension, a Bacillus subtilis suspension, a Bacillus megaterium suspension, a Bacillus pseudozopfii suspension or a Bacillus cohnii suspension.

3. The method for repairing concrete cracks by grouting based on biomimetic mineralization according to claim 1, characterized in that, The material of the soft suction disc is silicone rubber, polyurethane or chloroprene rubber.

4. The method for repairing concrete cracks by grouting based on biomimetic mineralization according to claim 1, characterized in that, The method further comprises: before injecting the material into the grouting hole, connecting the grouting hole to the vacuum pump through the vacuum pipe, and pumping air through the vacuum pump to suck out impurities in the concrete cracks, removing the vacuum pipe after the impurities in the concrete cracks are removed, injecting water from the grouting hole on the soft suction disc at one end of the concrete cracks until the inside of the concrete cracks is completely infiltrated, and then injecting the material from the grouting hole.

5. A method for repairing cracks in concrete by grouting based on biomimetic mineralization, characterized by, comprises: arranging the device at both ends and in the middle of the concrete cracks, aligning the grouting holes with the concrete cracks, and performing surface sealing on the cracks between adjacent devices; connecting the through holes to the vacuum pump through the vacuum pipe, and fixing the soft suction disc on the surface of the concrete cracks to be repaired by vacuumizing through the vacuum pump; injecting the material through the grouting hole on the soft suction disc in the middle of the concrete cracks, and using the grouting holes on the soft suction discs at both ends of the concrete cracks to collect waste liquid until the concrete cracks are completely blocked. The device comprises a soft suction disc, the lower surface of which is divided into an adsorption area and a crack grouting area, the crack grouting area being a strip-shaped groove completely covering the concrete cracks below the crack grouting area; The adsorption area has N through holes from the upper surface to the lower surface of the soft suction disc, which are used to connect a vacuum pump through a vacuum pipe when the device repairs concrete cracks, and the crack grouting area has M grouting holes from the upper surface to the lower surface of the soft suction disc, which are used to connect a grouting pipe when the device repairs concrete cracks, the material injected into the grouting pipe being a material for repairing concrete cracks based on biomimetic mineralization, wherein N≥1 and M≥1, and the material comprises: an A solution and a B solution; When the material is applied to repair concrete cracks, the A solution and the B solution are alternately grouted; The A solution is a calcium salt with a concentration of 0.2 mol / L-1.0 mol / L and a polymer with a concentration of 1 g / L-3 g / L, which is harmless to the environment, contains a polar functional group, and can be attracted to calcium carbonate, and the B solution is a carbonate salt with a concentration of 0.2 mol / L-1.0 mol / L; Alternatively, when the material is applied to repair concrete cracks, the A solution and the B solution are simultaneously grouted; A solution of 0.2 mol / L to 1.0 mol / L calcium salt, 0.2 mol / L to 1.0 mol / L urea and 1 g / L to 3 g / L of an environmentally friendly polymer containing a polar functional group and capable of producing an attraction to calcium carbonate, B solution of 10 7 CFU / mL ~ 10 8 urease bacteria suspension at 1.0 x 10 CFU / mL The polymer is carboxymethyl chitosan, polyaspartic acid, alginic acid, or welan gum, the calcium salt is calcium chloride, calcium acetate, calcium nitrate, heavy calcium carbonate, or calcium lactate, and the carbonate salt is sodium carbonate, lithium carbonate, or potassium carbonate.

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