A rapid repairing material for concrete cracks, and a preparation method and application thereof

Abstract

This invention belongs to the technical field of concrete crack filling materials, specifically relating to a rapid repair material for concrete cracks, comprising component A and component B. Component A contains liquid bisphenol A epoxy resin, filler, toughening agent, and anti-settling agent; component B includes a curing agent and a diluent. The curing agent is prepared by pre-reacting a polyamine, epoxy compound, and benzyl alcohol, followed by mixing with isocyanate. This invention has found that the synergistic effect of components A and B significantly improves the performance of the rapid repair material for concrete cracks. The research shows that this rapid repair material exhibits rapid strength growth at low temperatures, fast gel time, compressive strength greater than 50 MPa at 2 hours, flexural strength greater than 12 MPa at 24 hours, adhesive strength greater than 3.0 MPa, and the ability to open to traffic after 2 hours, with subsequent slow strength growth.

Description

Technical Field

[0001] This invention belongs to the technical field of concrete crack filling materials, specifically relating to a low-temperature rapid repair material for concrete cracks and its preparation method. Background Technology

[0002] In recent years, my country's high-speed railway construction has developed rapidly. Ballastless track is the mainstream track structure for my country's high-speed railways. During operation, high-speed railway ballastless tracks are subject to various defects due to long-term external forces and erosion from natural climate conditions. These defects include loosening, breakage, chipping, weathering, separation, and cracking of the concrete. If not repaired in time, these defects will worsen, leading to significant safety hazards and economic losses. Therefore, how to quickly repair these defects without affecting normal train operation has become a key concern for high-speed railway management departments.

[0003] Currently, the newest treatment method for ballastless track repair materials in my country's high-speed railways is to use polymer mortar to treat such defects. However, this method has problems such as slow strength growth at low temperatures, low bonding strength, and long opening time to traffic, which cannot meet the requirements of high-speed railway engineering for early strength, high strength, high bonding strength, and short opening time. Summary of the Invention

[0004] The purpose of this invention is to provide a low-temperature rapid repair material with rapid strength growth at low temperatures, fast gelation time, compressive strength greater than 50 MPa in 2 hours, flexural strength greater than 12 MPa in 24 hours, adhesive strength greater than 3.0 MPa, and the ability to open the road to traffic in 2 hours, with the strength continuing to grow slowly in the later stages.

[0005] A second objective of this invention is to provide the application of the aforementioned rapid repair material for concrete cracks.

[0006] To achieve the above technical parameters, the present invention adopts the following technical solution:

[0007] A quick-repair material for concrete cracks, comprising component A and component B;

[0008] Component A contains liquid bisphenol A epoxy resin, filler, toughening agent and anti-settling agent;

[0009] Component B includes a curing agent and a diluent;

[0010] The curing agent is prepared by reacting polyamine, epoxy compound and benzyl alcohol in advance, and then mixing it with isocyanate.

[0011] This invention has discovered that, based on the synergistic effect of components A and B, the performance of a rapid repair material for concrete cracks can be significantly improved. The study found that this rapid repair material exhibits characteristics such as rapid strength growth at low temperatures, fast gelation time, compressive strength greater than 50 MPa at 2 hours, flexural strength greater than 12 MPa at 24 hours, adhesive strength greater than 3.0 MPa, and the ability to open to traffic after 2 hours, with subsequent slow strength increases.

[0012] In this invention, the curing agent obtained according to the aforementioned components and special preparation method, and its synergistic effect with component A, are key to improving the low-temperature strength growth rate, shortening the gel time, and improving the strength of crack repair materials.

[0013] In this invention, the bisphenol A type epoxy resin is a polymer having the structural formula 1:

[0014]

[0015] Preferably, the bisphenol A type liquid epoxy resin has an epoxy equivalent of 185-190 eq / mol and a number-average molecular weight of 381-390 g / mol.

[0016] Preferably, the grade of the bisphenol A type liquid epoxy resin is CYD-128.

[0017] Preferably, the filler is silane-treated silicon micropowder; more preferably, the particle size of the silicon micropowder is 200-600 mesh.

[0018] Preferably, the toughening agent is butylene glycol glycidyl ether, polypropylene glycol glycidyl ether, polyethylene glycol glycidyl ether, benzyl glycidyl ether, or C. 12 -C 14 At least one of alkyl glycidyl ether and benzyl alcohol.

[0019] Preferably, the toughening agent is one or a combination of butanediol glycidyl ether, benzyl alcohol, and benzyl glycidyl ether.

[0020] Preferably, the anti-settling agent is nano-silica.

[0021] Preferably, the content of each component in component A, by weight, is as follows:

[0022] 80-90 parts of liquid bisphenol A type epoxy resin; preferably 85-90 parts;

[0023] 160-250 parts of filler

[0024] 10-20 parts toughening agent

[0025] 0.5-1 part of anti-settling agent.

[0026] In this invention, the composition of the curing agent and the special preparation method of reacting epoxy compound, polyamine and benzyl alcohol in advance and then mixing it with isocyanate are the key to achieving synergy with component A and improving the concrete repair effect.

[0027] Preferably, the polyamine is an alicyclic polyamine; more preferably, it is one or more of polyetheramine, isoflurane diamine, 1,3-diaminomethylcyclohexane, and 4,4′-diaminodicyclohexylmethane.

[0028] Preferably, the epoxy compound can be selected from one or more of epoxy resin, propylene oxide, ethylene oxide, and glycidyl ether diluent.

[0029] Preferably, during the synthesis of the curing agent, the mass ratio of polyamine, epoxy compound, and benzyl alcohol is 55-45:5-15:40; more preferably, it is 50-55:10-15:40.

[0030] Preferably, the reaction temperature is 40-90℃.

[0031] Preferably, the weight ratio of isocyanate to the unreacted polyamine is 15-40:50; more preferably, it is 25-35:50. The present invention unexpectedly discovered that, at the preferred ratio, combined with the specific treatment method described above, it helps to achieve even better strength results in a shorter time.

[0032] Preferably, the diluent is one or a combination of dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, and benzyl alcohol.

[0033] The content of each component in component B, by weight, is as follows:

[0034] 30-45 parts by weight of curing agent; more preferably 40-45 parts by weight.

[0035] Diluent 5-10 parts by weight.

[0036] Preferably, the mass ratio of component A to component B in the rapid repair material for concrete cracks is 3 to 10:1; more preferably 5 to 8:1.

[0037] The present invention also provides a method for preparing the aforementioned rapid repair material for concrete cracks, comprising the following steps:

[0038] A. Weigh the epoxy resin according to the formula requirements, heat it to 50-70℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand (5-15 min) to obtain component A (component A).

[0039] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand (5-15 minutes) to obtain component B (component B);

[0040] C. Mix components A and B at room temperature and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks.

[0041] The present invention also provides the application of the aforementioned rapid repair material for concrete cracks, wherein component A and component B are mixed for repairing concrete cracks.

[0042] The preferred application steps are as follows:

[0043] A. Weigh the epoxy resin according to the formula requirements, heat it to 50-70℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand (5-15 min) to obtain component A (component A).

[0044] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand (5-15 minutes) to obtain component B (component B);

[0045] C. Mix components A and B at room temperature and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Use the obtained material to repair concrete cracks.

[0046] In the application described in this invention, the crack is repaired within 10 minutes, preferably within 5 minutes, after mixing A (component A) and B (component B).

[0047] Preferably, the application is used for repairing cracks in the concrete of high-speed railway ballastless tracks.

[0048] The present invention has the following outstanding beneficial effects:

[0049] The low-temperature rapid repair material for concrete cracks of the present invention not only has low viscosity and excellent low-temperature permeability due to the high heat released by the curing reaction, but also promotes rapid curing of the material under low-temperature conditions.

[0050] The low-temperature rapid repair material for concrete cracks of the present invention exhibits rapid strength growth at low temperatures, with a compressive strength greater than 50 MPa in 2 hours, a flexural strength greater than 12 MPa in 24 hours, a bond strength greater than 3.0 MPa, and the strength continues to increase slowly in the later stages.

[0051] The low-temperature rapid repair material for concrete cracks of the present invention can shorten the time to open traffic, allowing traffic to resume in just 2 hours. Attached Figure Description

[0052] Figure 1These are images showing the application of the repair material described in Example 1 in the repair of ballastless track concrete on high-speed railways. The left image shows the joint before repair, the middle image shows the joint closed, and the right image shows the repaired joint. Detailed Implementation

[0053] To enhance the objectives, technical solutions, and beneficial effects of this invention, the following detailed explanation and description are provided in conjunction with specific embodiments.

[0054] The product application examples in this embodiment use adhesive strength testing, flexural strength testing, and compressive strength testing to evaluate performance.

[0055] Adhesion strength test: The performance test was carried out in accordance with the "Test Procedure for Polymer Modified Water Mortar" (DL / T 5126), and the test results are shown in Table 1.

[0056] Flexural strength and compressive strength tests: Performance tests were conducted in accordance with the Technical Specification for Bonding Repair of Concrete (JTJ / T 271), and the test results are shown in Table 1.

[0057] Example 1

[0058] Preparation steps of the self-made modified curing agent: 1,3-diaminomethylcyclohexane, polypropylene glycol glycidyl ether, and benzyl alcohol were mixed in a mass ratio of 50:10:40 and reacted at 60°C for 2 hours. Then, it was mixed with isocyanate (the mass ratio of isocyanate to 1,3-diaminomethylcyclohexane was 15:50) to obtain the self-made modified curing agent.

[0059] A quick-repair material for concrete cracks comprises the following components (by parts by weight).

[0060] Material A:

[0061]

[0062] Material B:

[0063] 35 parts of homemade modified curing agent

[0064] 5 parts of dibutyl phthalate

[0065] The steps are as follows:

[0066] A. Weigh the epoxy resin according to the formula requirements, heat it to 60℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand for 10 minutes to obtain component A.

[0067] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand for 10 minutes to obtain component B;

[0068] C. Mix components A and B at room temperature (mass ratio 6.5:1) and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Fill the concrete cracks with the mixture within 5 minutes of mixing.

[0069] Example 2

[0070] The preparation steps of the self-made modified curing agent are described as follows: For example, 1,3-diaminomethylcyclohexane, polypropylene glycol glycidyl ether, and benzyl alcohol in a mass ratio of 50:10:40 are mixed and reacted at 40°C for 2 hours. Then, it is mixed with isocyanate (the mass ratio of isocyanate to 1,3-diaminomethylcyclohexane is 25:50) to obtain the self-made modified curing agent.

[0071] A quick-repair material for concrete cracks comprises the following components (by parts by weight).

[0072] Material A:

[0073]

[0074]

[0075] Material B:

[0076] 45 parts of self-made modified curing agent

[0077] 5 parts of dibutyl phthalate

[0078] The steps are as follows:

[0079] A. Weigh the epoxy resin according to the formula requirements, heat it to 60℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand for 10 minutes to obtain component A.

[0080] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand for 10 minutes to obtain component B;

[0081] C. Mix components A and B at room temperature (mass ratio 7:1) and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Fill the concrete cracks with the mixture within 5 minutes of mixing.

[0082] Example 3

[0083] The preparation steps of the self-made modified curing agent are described as follows: For example, 1,3-diaminomethylcyclohexane, polypropylene glycol glycidyl ether, and benzyl alcohol in a mass ratio of 50:10:40 are mixed and reacted at 40°C for 2 hours. Then, it is mixed with isocyanate (the mass ratio of isocyanate to 1,3-diaminomethylcyclohexane is 35:50) to obtain the self-made modified curing agent.

[0084] A quick-repair material for concrete cracks comprises the following components (by parts by weight).

[0085] Material A:

[0086]

[0087] Material B:

[0088] 42 parts of self-made modified curing agent

[0089] 5 parts of dibutyl phthalate

[0090] The steps are as follows:

[0091] A. Weigh the epoxy resin according to the formula requirements, heat it to 60℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand for 10 minutes to obtain component A.

[0092] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand for 10 minutes to obtain component B;

[0093] C. Mix components A and B at room temperature (mass ratio 5.54:1) and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Fill the concrete cracks with the mixture within 5 minutes of mixing.

[0094] Example 4

[0095] Homemade curing agent, same as in Example 2.

[0096] A quick-repair material for concrete cracks comprises the following components (by parts by weight).

[0097] Material A:

[0098]

[0099] Material B:

[0100] 40 parts of homemade modified curing agent

[0101] 10 parts of dibutyl phthalate

[0102] The steps are as follows:

[0103] A. Weigh the epoxy resin according to the formula requirements, heat it to 60℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand for 10 minutes to obtain component A.

[0104] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand for 10 minutes to obtain component B;

[0105] C. Mix components A and B at room temperature (mass ratio 7:1) and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Fill the concrete cracks with the mixture within 5 minutes of mixing.

[0106] Example 5

[0107] Homemade curing agent, same as in Example 2.

[0108] A quick-repair material for concrete cracks comprises the following components (by parts by weight).

[0109] Material A:

[0110]

[0111] Material B:

[0112] 44 parts of self-made modified curing agent

[0113] 5 parts of dibutyl phthalate

[0114] The steps are as follows:

[0115] A. Weigh the epoxy resin according to the formula requirements, heat it to 60℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand for 10 minutes to obtain component A.

[0116] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand for 10 minutes to obtain component B;

[0117] C. Mix components A and B at room temperature (mass ratio 5.32:1) and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Fill the concrete cracks with the mixture within 5 minutes of mixing.

[0118] Example 6

[0119] The preparation steps of the self-made modified curing agent are described as follows: For example, 1,3-diaminomethylcyclohexane, polypropylene glycol glycidyl ether, and benzyl alcohol in a mass ratio of 50:10:40 are mixed and reacted at 40°C for 2 hours. Then, it is mixed with isocyanate (the mass ratio of isocyanate to 1,3-diaminomethylcyclohexane is 25:50) to obtain the self-made modified curing agent.

[0120] A quick-repair material for concrete cracks comprises the following components (by parts by weight).

[0121] Material A:

[0122]

[0123] Material B:

[0124] 45 parts of self-made modified curing agent

[0125] 10 parts of dibutyl phthalate

[0126] The steps are as follows:

[0127] A. Weigh the epoxy resin according to the formula requirements, heat it to 60℃, and add toughening agent, filler and anti-settling agent while stirring. After mixing evenly, let it stand for 10 minutes to obtain component A.

[0128] B. Weigh the curing agent and diluent according to the formula requirements, mix them evenly, and let them stand for 10 minutes to obtain component B;

[0129] C. Mix components A and B at room temperature (mass ratio 5.8:1) and stir until homogeneous to obtain a low-temperature rapid repair material for concrete cracks. Fill the concrete cracks with the mixture within 5 minutes of mixing.

[0130] Comparative Example 1:

[0131] Compared to Example 2, in the preparation of the curing agent, the required amounts of polyamine, epoxy compound and benzyl alcohol were mixed and reacted together, but isocyanate was not added. Instead, 8 parts of DMP-30 were added to component B, and other conditions were the same as in Example 2.

[0132] Comparative Example 2:

[0133] Compared to Example 2, in the preparation of the curing agent, the required amounts of polyamine, epoxy compound and benzyl alcohol were mixed and reacted together, but isocyanate was not added. Instead, 8 parts of BDMA were added to component B, and other conditions were the same as in Example 2.

[0134] Comparative Example 3:

[0135] Compared to Example 2, the only difference is that isocyanate was not added during the preparation of the curing agent.

[0136] Comparative Example 4:

[0137] Compared to Example 2, the curing agent was prepared by mixing and reacting the required amounts of polyamine, epoxy compound, benzyl alcohol and isocyanate together under the same conditions as in Example 2.

[0138] Table 1. Performance test results of rapid repair materials for concrete cracks in each embodiment and comparative example.

[0139]

[0140] As shown in Table 1, the preparation method of the curing agent involves pre-reacting the polyamine, epoxy compound, and benzyl alcohol, followed by combination with isocyanate. While the isocyanate does not participate in the grafting modification reaction, its innovative addition unexpectedly improves the synergistic effect between the prepared curing agent and component A, thus enhancing the performance of the crack filling material. The study found that this rapid-repair material for concrete cracks exhibits rapid strength growth at low temperatures, with a 2-hour compressive strength greater than 50 MPa, a 24-hour flexural strength greater than 12 MPa, and a bond strength greater than 3.0 MPa. It can gel rapidly, shortening the time before traffic can resume, thus meeting the requirements for low-temperature repair of concrete cracks, which include high 2-hour compressive strength, high 24-hour flexural strength, high bond strength, and short open time.

Claims

1. A rapid repair material for concrete cracks, characterized by, The composition comprises a component A and a component B; The component A comprises a liquid bisphenol A type epoxy resin, a filler, a toughening agent and an anti-settling agent; The component B comprises a curing agent and a diluent; The curing agent is prepared by mixing a polyamine, an epoxy compound and benzyl alcohol with isocyanate; The liquid bisphenol A type epoxy resin is a polymer with the structure of formula 1: Formula 1 The number average molecular weight of the liquid bisphenol A type epoxy resin is 381-390 g / mol; The epoxy compound is at least one of an epoxy resin, propylene oxide, ethylene oxide and glycidyl ether diluent; The polyamine is at least one of polyether amine, isophorone diamine, 1,3-diaminomethylcyclohexane and 4,4'-diaminodicyclohexyl methane; The component A comprises a component A and a component B; The liquid bisphenol A type epoxy resin is 80-90 parts by weight; The filler is 160-250 parts by weight The toughening agent is 10-20 parts by weight The anti-settling agent is 0.5-1 part by weight. The component B comprises a curing agent and a diluent.

2. The rapid patching material for concrete cracks according to claim 1, wherein The liquid bisphenol A type epoxy resin is CYD-128.

3. The rapid patching material for concrete cracks according to claim 1, wherein The filler is silane treated silica powder.

4. The rapid patching material for concrete cracks according to claim 3, wherein the water is added in an amount of 0.1 to 0.3 parts by weight based on 100 parts by weight of the cement. The particle size of the silica powder is 200-600 mesh.

5. The rapid patching material for concrete cracks according to claim 1, wherein The flexibilizer is at least one of butylene glycol glycidyl ether, polypropylene glycol glycidyl ether, polyethylene glycol glycidyl ether, benzyl glycidyl ether, C 12 -C 14 alkyl glycidyl ether, benzyl alcohol.

6. The rapid patching material for concrete cracks according to claim 5, wherein The toughening agent is one or a combination of butanediol glycidyl ether, benzyl alcohol and benzyl glycidyl ether.

7. The rapid patching material for concrete cracks according to claim 1, wherein The anti-settling agent is nano-silica.

8. The rapid patching material for concrete cracks according to claim 1, wherein The mass ratio of the polyamine, the epoxy compound and benzyl alcohol in the synthesis of the curing agent is 55-45:5-15:

40.

9. The rapid patching material for concrete cracks according to claim 1, wherein The temperature of the reaction in the synthesis of the curing agent is 40-90℃.

10. The rapid patching material for concrete cracks according to claim 1, wherein The weight ratio of isocyanate to the polyamine before reaction is 15-40:

50.

11. The rapid patching material for concrete cracks according to claim 10, wherein the polyol is a polyhydric alcohol having 2 to 6 hydroxyl groups. The weight ratio of isocyanate to the polyamine before reaction is 25-35:

50.

12. The rapid patch material for concrete cracks according to claim 1, wherein The diluent is one or a combination of dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate and benzyl alcohol.

13. The rapid patch material for concrete cracks according to claim 1, wherein The mass ratio of the component A to the component B is 3-10:

1.

14. The rapid patching material for concrete cracks according to claim 13, wherein the polyol is a polyhydric alcohol having 2 to 6 hydroxyl groups. The mass ratio of the component A to the component B is 5-8:

1.

15. Use of the rapid repair material for concrete cracks according to any one of claims 1 to 14, characterized in that, The component A and the component B are mixed and used for repairing cracks in concrete.

16. The use of the rapid repair material for concrete cracks according to claim 15, wherein The cracks are repaired within 10 minutes after mixing the component A and the component B.

17. The use of a rapid repair material for concrete cracks according to claim 16, wherein It is used for repairing cracks in high-speed rail concrete.

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