A method for preparing a slow-releasing foamed cement-based grouting material

Abstract

The application discloses a kind of slow-release foamed cement-based grouting material preparation methods, belong to building material technical field.Slow-release foamed cement-based grouting material includes the following mass fraction of raw materials: cementing material 800~900 parts, heavy calcium powder 100~200 parts, foaming agent 5~15 parts, catalyst 4~6 parts, calcium stearate 8~10 parts, foam stabilizer 0.1~0.2 parts, coating agent 0.1~0.5 parts, water reducing agent 1~5 parts, coagulant 0~0.5 parts, early strength agent 0~8 parts, polypropylene fiber 0~5 parts, redispersible emulsion powder 2~10 parts and water 300~350 parts.The slow-release foamed cement-based grouting material of the application can start to react and foam after grouting is completed after slurry stirring, can improve the early strength of material, and can meet the requirements of road rapid repair.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to a method for preparing a slow-release foamed cement-based grouting material. Background Technology

[0002] In recent years, with the continuous improvement of road traffic infrastructure, the role of highway maintenance in the development of the transportation industry has gradually increased, and the tasks of road maintenance, repair, reconstruction, and reinforcement at all levels have become increasingly heavy. As the service life of roads continues to increase, defects such as pavement cracks, foundation settlement, and bridge approach slab settlement are gradually emerging. When problems occur in the roadbed and pavement, grouting can be used for repair. Its simple operation, small construction volume, and ability to quickly restore traffic have gradually made it a favorite among engineers, becoming a major method for roadbed reinforcement and maintenance projects.

[0003] Ordinary cement is the most commonly used cement-based grouting material. However, ordinary cement has a large particle size, poor fluidity, and a large self-weight, resulting in rapid settlement. Its grouting effect on micro-cracks needs improvement. Therefore, finding a grouting material that can be adapted for rapid repair is of great significance for reinforcing and maintaining the service performance and durability of roadbeds.

[0004] Rapid roadbed reinforcement and repair technology needs to meet the following requirements: rapid strength formation, simple process, energy saving and environmental protection, and long service life. Currently, commonly used roadbed repair grouting materials are usually filled after mixing and when the reaction begins, which brings great inconvenience to the construction operation.

[0005] Currently, some research has been conducted on foamed cement grouting technology for roadbed repair. This technology involves introducing air into the cement grout through physical or chemical foaming to form microbubbles. The solidified bubble structure significantly reduces the material density, giving it lightweight and earthquake-resistant properties. This reduced grout density allows the grout to self-expand and fill voids in tiny gaps. However, the performance of traditional foamed cement grouting is highly dependent on the material ratio, the choice of foaming agent, and the mixing process. Physically foamed cement has a relatively cumbersome operation process, requiring foam to be prepared and introduced into the cement grout before mixing, placing high demands on construction conditions. Chemically foamed cement requires careful selection of foaming components; the air-generating capacity of the foaming agent must match the grout's fluidity, otherwise, it will result in inconsistent bubble size and uneven distribution, affecting the quality of the grouting repair. Furthermore, traditional foamed cement grouting begins to react and expand during mixing. Early foaming may lead to uneven distribution of air bubbles, affecting the expansion strength of the repair grout. After grouting, it cannot expand and fill the voids in the roadbed defects. In addition, the cement grout has a high density and the preparation process is relatively complicated, making it difficult to meet the requirements of rapid road repair.

[0006] Therefore, it is necessary to find a slow-release foamed cement material that can self-expand after grouting and has the characteristics of being lightweight and having early strength, in order to meet the requirements of rapid road repair. Summary of the Invention

[0007] The purpose of this invention is to provide a highly elastic waterproof coating based on functionally modified rubber, its preparation method, and its application, so as to solve the problems existing in the prior art.

[0008] To achieve the above objectives, the present invention provides the following solution:

[0009] One of the technical solutions of the present invention is a slow-release foaming cement-based grouting material, comprising the following raw materials in parts by weight: 800-900 parts of cementitious material, 100-200 parts of heavy calcium carbonate powder, 5-15 parts of foaming agent, 4-6 parts of catalyst, 8-10 parts of calcium stearate, 0.1-0.2 parts of foam stabilizer, 0.1-0.5 parts of coating agent, 1-5 parts of water-reducing agent, 0-0.5 parts of setting accelerator, 0-8 parts of early strength agent, 0-5 parts of polypropylene fiber, 2-10 parts of redispersible latex powder, and 300-350 parts of water.

[0010] Furthermore, the slow-release foaming cement-based grouting material comprises the following raw materials in parts by weight: 900 parts of cementitious material, 100 parts of heavy calcium carbonate powder, 10 parts of foaming agent, 6 parts of catalyst, 10 parts of calcium stearate, 0.1 parts of foam stabilizer, 0.25 parts of coating agent, 3 parts of water-reducing agent, 0.2 parts of setting accelerator, 8 parts of early strength agent, 4 parts of polypropylene fiber, 10 parts of redispersible latex powder, and 338 parts of water.

[0011] Furthermore, the coating agent includes a titanate coupling agent.

[0012] Furthermore, the titanate coupling agent includes one or more of fatty acid ester type coupling agents, phosphate ester type coupling agents, and pyrophosphate ester type coupling agents; the titanate coupling agent can delay foaming after the foaming component is added with water, thus meeting the foaming requirements after grouting.

[0013] Furthermore, the catalyst comprises manganese dioxide particles.

[0014] Furthermore, the particle size of the manganese dioxide particles is 100-150 mesh.

[0015] Furthermore, the cementitious material includes aluminate cement CA50;

[0016] Furthermore, the alumina content of the aluminate cement CA50 is 51.05%, and the specific surface area is 397 m². 2 / kg;

[0017] Furthermore, the particle size of the heavy calcium carbonate powder is 800-1250 mesh;

[0018] Furthermore, the foaming agent includes hydrogen peroxide particles;

[0019] Furthermore, the particle size of the hydrogen peroxide particles is 100-150 mesh;

[0020] Furthermore, the foam stabilizer includes hydroxymethyl cellulose ether;

[0021] Furthermore, the water-reducing agent includes a polycarboxylate-based water-reducing agent;

[0022] Furthermore, the coagulant includes lithium carbonate;

[0023] Furthermore, the early strength agent is selected from one of calcium chloride, calcium formate, and sodium sulfate; calcium chloride can improve the setting time of the material and increase its early strength.

[0024] Furthermore, the length of the polypropylene fiber is 8-12 mm; the polypropylene fiber can improve the flexural strength of the material and enhance its crack resistance.

[0025] Furthermore, the particle size of the redispersible latex powder is 400-1250 mesh; the redispersible latex powder can improve the toughness of the material and reduce the water absorption rate.

[0026] Heavy calcium carbonate powder and early strength agents can stabilize the long-term strength of materials and improve their early strength.

[0027] The second technical solution of the present invention: a method for preparing the above-mentioned slow-release foamed cement-based grouting material, comprising the following steps:

[0028] After the coating agent is dispersed evenly in water, the catalyst is added, mixed evenly, dried, and ground to obtain the modified catalyst.

[0029] The modified catalyst, cementing material, heavy calcium carbonate powder and raw materials other than water are mixed evenly to prepare the additive;

[0030] The cementitious material and heavy calcium carbonate powder are mixed evenly, and then the admixture and modified catalyst are added and mixed evenly. Water is then added and mixed evenly to obtain the slow-release foaming cement-based grouting material.

[0031] Furthermore, the grinding is performed until the particle size is 100-300 mesh.

[0032] This invention modifies the foaming component (manganese dioxide particles) of foamed cement by using a coating agent, enabling it to begin foaming after the grout mixing is completed. In terms of strength, the addition of an early-strength agent improves the early strength of the material, which is more conducive to ensuring the strength stability of the grouting material under different temperature conditions. The addition of heavy calcium carbonate powder stabilizes the long-term strength of the material. In terms of durability, the addition of redispersible latex powder and polypropylene fiber improves the toughness of the material and reduces its water absorption rate.

[0033] The third technical solution of the present invention: the application of the above-mentioned slow-release foaming cement-based grouting material in road maintenance and repair.

[0034] The present invention discloses the following technical effects:

[0035] (1) The slow-release foaming cement-based grouting material of the present invention can start to react and foam after the grout is mixed and injected, which can improve the early strength of the material and meet the requirements of rapid road repair.

[0036] (2) The slow-release foamed cement-based grouting material of the present invention is lightweight, has low water absorption, high early strength, and good flexural strength and toughness. Detailed Implementation

[0037] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0038] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0039] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0040] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0041] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0042] In the following examples, "parts" refers to "parts by weight".

[0043] Example 1

[0044] A method for preparing a slow-release foamed cement-based grouting material:

[0045] (1) Slow-release foaming cement-based grouting material is composed of the following raw materials in parts by weight: 900 parts of cementitious material, 100 parts of heavy calcium carbonate powder, 10 parts of foaming agent, 6 parts of catalyst, 10 parts of calcium stearate, 0.1 parts of foam stabilizer, 0.25 parts of coating agent, 3 parts of water-reducing agent, 0.2 parts of coagulating agent, 8 parts of early strength agent, 4 parts of polypropylene fiber, 10 parts of redispersible latex powder and 338 parts of water.

[0046] The cementing material is aluminate cement CA50, with an alumina content of 51.05% and a specific surface area of ​​397 m². 2 / kg;

[0047] The particle size of the heavy calcium carbonate powder is 800 mesh;

[0048] The foaming agent is hydrogen peroxide particles with a particle size of 150 mesh;

[0049] The catalyst is manganese dioxide particles with a particle size of 150 mesh;

[0050] Foam stabilizer hydroxymethyl cellulose ether;

[0051] The coating agent is a monoalkoxy fatty acid ester type coupling agent (monoalkoxy fatty acid ester titanate coupling agent CS-101(TTS));

[0052] The water-reducing agent is a polycarboxylate-based water-reducing agent;

[0053] The coagulant is lithium carbonate;

[0054] The early-strength agent is calcium chloride;

[0055] The length of the polypropylene fibers is 8–12 mm;

[0056] The particle size of the redispersible latex powder is 400 mesh.

[0057] (2) Preparation of slow-release foamed cement-based grouting material:

[0058] A. First, dilute the coating agent with water. After dilution, add the catalyst (manganese dioxide particles) to the container and stir evenly to form a mixture. Then, put it into a 100°C oven to dry. After drying, put it into a ball mill to crush it and pass it through a 150-mesh sieve to obtain the modified catalyst.

[0059] B. Mix the modified catalyst, cementing material, heavy calcium carbonate powder and raw materials other than water evenly to obtain the additive.

[0060] C. Mix the cementitious material and heavy calcium carbonate powder evenly, add the admixture and modified catalyst, mix evenly, and then add them together with water into a mixer and stir evenly to obtain a slow-release foaming cement-based grouting material.

[0061] Example 2

[0062] Same as Example 1, except that the slow-release foaming cement-based grouting material is composed of the following raw materials in parts by weight: 850 parts of cementitious material, 150 parts of heavy calcium carbonate powder, 10 parts of foaming agent, 6 parts of catalyst, 10 parts of calcium stearate, 0.1 parts of foam stabilizer, 0.2 parts of coating agent, 3 parts of water-reducing agent, 0.2 parts of setting accelerator, 8 parts of early strength agent, 3 parts of polypropylene fiber, 8 parts of redispersible latex powder, and 330 parts of water.

[0063] Example 3

[0064] Same as Example 1, except that the slow-release foaming cement-based grouting material is composed of the following raw materials in parts by weight: 900 parts cement, 100 parts heavy calcium carbonate powder, 10 parts foaming agent, 6 parts catalyst, 10 parts calcium stearate, 0.1 parts foam stabilizer, 0.15 parts coating agent, 3 parts water-reducing agent, 0.2 parts accelerator, 2 parts polypropylene fiber, 6 parts redispersible latex powder, and 330 parts water.

[0065] Example 4

[0066] Same as Example 1, except that the slow-release foaming cement-based grouting material is composed of the following raw materials in parts by weight: 900 parts cement, 100 parts heavy calcium carbonate powder, 10 parts foaming agent, 6 parts catalyst, 10 parts calcium stearate, 0.1 parts foam stabilizer, 0.1 parts coating agent, 3 parts water-reducing agent, 0.2 parts accelerator, 8 parts early strength agent, 4 parts redispersible latex powder, and 330 parts water.

[0067] Example 5

[0068] Same as Example 1, except that the slow-release foaming cement-based grouting material is composed of the following raw materials in parts by weight: 900 parts cement, 100 parts heavy calcium carbonate powder, 10 parts foaming agent, 6 parts catalyst, 10 parts calcium stearate, 0.1 parts foam stabilizer, 0.25 parts coating agent, 3 parts water-reducing agent, 8 parts early strength agent, 2 parts polypropylene fiber, 5 parts redispersible latex powder, and 330 parts water.

[0069] The slow-release foamed cement-based grouting materials prepared in Examples 1 to 5 were injected into a 40mm×40mm×160mm mold and cured in a curing chamber at a temperature of 20±5℃ and a humidity of 90%. The physical and mechanical properties of the specimens prepared in Examples 1 to 5 were tested, and the results are shown in Table 1.

[0070] Table 1 Physical and Mechanical Properties

[0071]

[0072]

[0073] Comparative Example 1

[0074] Same as Example 1, except that (1) the slow-release foaming cement-based grouting material is composed of the following raw materials in parts by weight: 900 parts of cementitious material, 100 parts of heavy calcium carbonate powder, 10 parts of foaming agent, 10 parts of calcium stearate, 0.1 parts of foam stabilizer, 3 parts of water-reducing agent, 0.2 parts of accelerator, 8 parts of early strength agent, 4 parts of polypropylene fiber, 10 parts of redispersible latex powder and 338 parts of water.

[0075] (2) Preparation of slow-release foamed cement-based grouting material:

[0076] A. Mix the raw materials other than the cementitious materials, heavy calcium carbonate powder and water evenly to prepare the additive.

[0077] B. Mix the cementitious material and heavy calcium carbonate powder evenly, add the admixture and mix evenly, then add it together with water into the mixer and stir evenly to obtain foamed cement grouting material.

[0078] Comparative Example 2

[0079] Same as Example 1, except that the coating agent is sodium alginate.

[0080] The cement-based grouting materials prepared in Comparative Examples 1 and 2 were used to prepare specimens for physical and mechanical property testing according to the above method. The results are shown in Table 2.

[0081] Table 2 Physical and Mechanical Properties

[0082]

[0083] No catalyst was added in Comparative Example 1, and the slurry had almost no expansion, so it had a high dry density and was a high-strength mortar specimen, but it could not fill the voids in the dark well.

[0084] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A slow-release foaming cement-based grouting material, characterized in that, It is composed of the following raw materials in parts by weight: 800-900 parts of cementitious material, 100-200 parts of heavy calcium carbonate powder, 5-15 parts of foaming agent, 4-6 parts of catalyst, 8-10 parts of calcium stearate, 0.1-0.2 parts of foam stabilizer, 0.1-0.5 parts of coating agent, 1-5 parts of water-reducing agent, 0-0.5 parts of coagulating agent, 0-8 parts of early strength agent, 0-5 parts of polypropylene fiber, 2-10 parts of redispersible latex powder, and 300-350 parts of water; The coating agent is a titanate coupling agent; the titanate coupling agent is one or more of fatty acid ester type coupling agents, phosphate ester type coupling agents, and pyrophosphate ester type coupling agents; The catalyst is manganese dioxide particles.

2. The slow-release foamed cement-based grouting material according to claim 1, characterized in that, It is composed of the following raw materials in parts by weight: 900 parts of cementitious material, 100 parts of heavy calcium carbonate powder, 10 parts of foaming agent, 6 parts of catalyst, 10 parts of calcium stearate, 0.1 parts of foam stabilizer, 0.25 parts of coating agent, 3 parts of water-reducing agent, 0.2 parts of coagulating agent, 8 parts of early strength agent, 4 parts of polypropylene fiber, 10 parts of redispersible latex powder, and 338 parts of water.

3. A method for preparing the slow-release foamed cement-based grouting material according to claim 1 or 2, characterized in that, Includes the following steps: After the coating agent is dispersed evenly in water, the catalyst is added, mixed evenly, dried, and ground to obtain the modified catalyst. The modified catalyst, cementing material, heavy calcium carbonate powder, and raw materials other than water are mixed evenly to prepare the additive; The cementitious material and heavy calcium carbonate powder are mixed evenly, and then the admixture and modified catalyst are added and mixed evenly. Water is then added and mixed evenly to obtain the slow-release foaming cement-based grouting material.

4. The preparation method according to claim 3, characterized in that, The grinding process involves grinding the material to a particle size of 100-300 mesh.

5. The application of the slow-release foamed cement-based grouting material as described in claim 1 or 2 in road maintenance and repair.

Images