CN-122010524-A - Low-shrinkage high-adhesion concrete crack repairing agent and preparation method thereof

Abstract

The invention provides a low-shrinkage high-adhesion concrete crack repairing agent and a preparation method thereof, and relates to the field of concrete crack repairing, the concrete crack repairing agent comprises (by mass) 100 parts of inorganic dry powder and a microbial liquid agent, wherein the inorganic dry powder comprises 60-75 parts of active magnesium oxide, 9-16 parts of monopotassium phosphate or monoammonium phosphate, 10-20 parts of fly ash or silica fume, 5-15 parts of boron compound, 10-25 parts of bacterial strain liquid, 1.2-3 parts of a nutrient source, 1.7-5 parts of a calcium source and 0-25 parts of distilled water, and the concrete crack repairing agent with the characteristics of rapidness, early strength, good adhesion, good environmental friendliness and the like is developed by combining the induction mineralization capability of microorganisms with the rapid hardening and early strength characteristics of inorganic cementing materials.

Inventors

• RONG HUI
• LI BO
• Yuan Wenna
• LIU ZHIHUA
• WANG HAILIANG
• LIU DEE
• YANG XINLEI
• YANG YONG

Assignees

• 天津城建大学

Dates

Publication Date

20260512

Application Date

20260416

Claims (8)

1. 1. The low-shrinkage high-adhesion concrete crack repairing agent is characterized by comprising, by mass, 100 parts (20-30) of inorganic dry powder and a microbial liquid, wherein the inorganic dry powder comprises 60-75 parts of active magnesium oxide, 9-16 parts of potassium dihydrogen phosphate or ammonium dihydrogen phosphate, 10-20 parts of fly ash or silica fume and 5-15 parts of boron compound, the microbial liquid comprises 10-25 parts of bacterial seed liquid, 1.2-3 parts of a nutrient source, 1.7-5 parts of a calcium source and 0-25 parts of distilled water, and the bacterial seed liquid can keep urease activity in a cement matrix and induce generation of calcium carbonate.
2. 2. The low shrinkage high adhesion concrete crack repairing agent according to claim 1, further comprising 0-3 parts of a toner, wherein the toner is an inorganic pigment for adjusting the color of the repairing agent to be consistent with a target area.
3. 3. The low shrinkage high adhesion concrete crack repairing agent according to claim 1, wherein the bacterial seed liquid is urea decomposition type bacterial seed liquid, and the microorganism concentration is 10 8 -10 10 cells/ml.
4. 4. The low shrinkage and high adhesion concrete crack repairing agent according to claim 3, wherein the ureolytic bacterial strain liquid is ureolytic bacterial strain with mineralization induction capability, and comprises one or more of bacillus pasteurizus, bacillus subtilis and bacillus megaterium.
5. 5. The low shrinkage high adhesion concrete crack repairing agent according to claim 1, wherein the nutrient source is one or more of urea, tryptone, beef extract, casein peptone, sodium chloride, agar.
6. 6. The low shrinkage high adhesion concrete crack repairing agent according to claim 1, wherein the calcium source is one or more of calcium acetate, calcium lactate, and calcium nitrate.
7. 7. The preparation method of the low-shrinkage high-adhesion concrete crack repairing agent is characterized by comprising the following steps of: the low shrinkage high adhesion concrete crack repairing agent according to any one of claims 1 to 6, which is prepared as a raw material in a material ratio and processed by: Adding 100 parts of inorganic dry powder materials comprising magnesium oxide, potassium dihydrogen phosphate or ammonium dihydrogen phosphate, fly ash or silica fume, 0-3 parts of toner and boron compound into a first container, and uniformly stirring by using a cement paste stirrer; adding 20-30 parts of microbial liquid material comprising bacterial strain liquid, a nutrient source, a calcium source and 0-25 parts of distilled water into a second container, and fully stirring; And adding the microbial solution in the second container into the dry powder mixture in the first container, and fully stirring by using a cement paste stirrer to obtain a finished product of the repairing agent.
8. 8. The method for preparing a low shrinkage high adhesion concrete crack repairing agent according to claim 7, further comprising: before the finished product of the repairing agent is used, spraying bacterial liquid capable of generating calcium carbonate on a concrete basal plane to be repaired; and after the calcium carbonate network structure is formed on the concrete base, smearing the repairing agent finished product.

Description

Low-shrinkage high-adhesion concrete crack repairing agent and preparation method thereof Technical Field The invention relates to the technical field of concrete crack repair, in particular to a low-shrinkage high-adhesion concrete crack repair agent and a preparation method thereof. Background The concrete is used as a core material in the fields of building, traffic, water conservancy and the like, and is widely applied to engineering structures such as house building, bridges, tunnels, dykes and the like. However, under the action of construction process, service environment and external load, concrete structures are extremely prone to crack of different dimensions. The cracks not only can damage the integrity and the aesthetic property of the concrete, but also can become channels for invasion of corrosive media such as moisture, chloride ions, carbon dioxide and the like, accelerate corrosion of reinforcing steel bars and degradation of internal structures, seriously reduce the bearing capacity, durability and service life of the concrete structure, even cause structural potential safety hazards, and cause huge economic loss and safety risks. In the current concrete crack repairing agent, a series of high-performance repairing materials are sequentially developed, including inorganic, organic-inorganic composite and microorganism, so that the mechanical property and durability of crack repairing are remarkably improved, but the repairing materials still have the defects of poor cohesiveness, secondary cracking, complex construction and the like. In the process of realizing the invention, the applicant finds that the microbial repairing material becomes a research hot spot due to the advantages of environmental protection and sustainability, wherein the urease-producing bacteria have high urease activity and can form spores to resist severe environments, but when the microbial repairing material is independently applied, the structural bearing requirement is difficult to quickly meet, the interface bonding strength with a concrete matrix is limited, and the repairing efficiency and range are further limited. The inorganic repairing material has the characteristics of high coagulation speed, high early strength, good compatibility with a concrete matrix and the like, has potential in the field of emergency repairing, but has the defects of large shrinkage rate and easiness in generating micro cracks when being singly used, lacks continuous repairing capability, cannot cope with cracks caused by secondary cracking possibly occurring in the service process of the concrete, and has insufficient repairing durability. Therefore, how to reduce the shrinkage of the concrete repair material and improve the repair durability is a technical problem to be solved. Disclosure of Invention The invention aims at least solving one of the technical problems in the prior art or related technologies, and discloses a low-shrinkage high-adhesion concrete crack repairing agent and a preparation method thereof. The invention discloses a low-shrinkage high-adhesion concrete crack repairing agent which comprises, by mass, 100 parts (20-30 parts) of inorganic dry powder and a microbial liquid, wherein the inorganic dry powder comprises 60-75 parts of active magnesium oxide, 9-16 parts of monopotassium phosphate or monoammonium phosphate, 10-20 parts of fly ash or silica fume and 5-15 parts of boron compound, the microbial liquid comprises 10-25 parts of bacterial strain liquid, 1.2-3 parts of a nutrient source, 1.7-5 parts of a calcium source and 0-25 parts of distilled water, and the bacterial strain liquid can keep urease activity in a cement matrix and induce generation of calcium carbonate. The low-shrinkage high-adhesion concrete crack repairing agent disclosed by the invention preferably further comprises 0-3 parts of toner, wherein the toner is inorganic pigment and is used for adjusting the color of the repairing agent to be consistent with a target area. According to the low-shrinkage high-adhesion concrete crack repairing agent disclosed by the invention, preferably, the bacterial seed liquid is urea-decomposition type bacterial seed liquid, and the microorganism concentration is 10 8-1010 cells/ml. According to the low-shrinkage high-adhesion concrete crack repairing agent disclosed by the invention, preferably, the urea-decomposing bacterial strain liquid is urea-decomposing bacteria with mineralization induction capability, and comprises one or more of bacillus barbitarvensis, bacillus subtilis and bacillus megaterium. The low shrinkage and high adhesion concrete crack repairing agent disclosed by the invention is preferably one or more of urea, tryptone, beef extract, casein peptone, sodium chloride and agar as a nutrient source. The low-shrinkage high-adhesion concrete crack repairing agent disclosed by the invention is preferably one or more of calcium acetate, calcium lactate and calcium nitrate. The invention a