Self-expanding prestressed grouting material and preparation method thereof

Abstract

The present invention discloses a self-expanding prestressed grouting material and a preparation method thereof. The grouting material comprises the following components by weight: 12-15 parts of a self-stressing active material, 1-2 parts of an antioxidant, 1-2 parts of an interfacial stabilizer, 1-2 parts of a crystallization accelerator, 1-3 parts of a coagulant, 3-5 parts of a reinforcing agent, and 100-120 parts of a cementitious material. By introducing the self-stressing active material into the grouting material, the present invention can effectively improve the compressive strength, tensile strength, durability, shock resistance, and toughness of the grouting material, thereby improving the grouting effect. Furthermore, the grouting material has a simple preparation process, low cost, and is easy to promote and use.

Description

Technical Field

[0001] The present invention belongs to the technical field of grouting material preparation, and in particular, relates to a self-expanding prestressed grouting material and a preparation method thereof. Background Art

[0002] As the depth of coal mining increases, large deformation problems occur in the surrounding rock of coal mine tunnels. Grouting modification is an effective means of controlling the surrounding rock of tunnels, and has achieved good reinforcement effects. The concept of prestressed support refers to a technology that protects the stability of tunnels by resisting external forces by pre-applying stress. Its core idea is to apply a certain tension to the tunnel surrounding rock through prestressed anchors and grouting material systems before the tunnel surrounding rock is affected by external forces, so as to constrain the surrounding rock and reduce its stress state to prevent damage to the tunnel. Prestressed support technology is widely used in tunnel support under various complex geological conditions, especially in difficult and complex tunnels with large sections, geological structure damage areas, weak and thick roofs, high ground stress, etc. At present, there are few reports on the research of prestressed grouting materials in grouting modification for tunnel surrounding rock reinforcement.

[0003] In view of this, the present invention is proposed. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the present invention provides a simple, low-cost, and effective self-expanding prestressed grouting material and a preparation method thereof, and promotes its application.

[0005] On the one hand, an embodiment of the present invention provides a self-expanding prestressed grouting material, comprising the following components in parts by mass: 12-15 parts of self-stress active material, 1-2 parts of antioxidant, 1-2 parts of interface stabilizer, 1-2 parts of crystallization promoter, 1-3 parts of coagulant, 3-5 parts of reinforcing agent, and 100-120 parts of cementitious material.

[0006] In some embodiments, the self-stress active material is a mixture of calcium carbide and aluminum carbide;

[0007] Preferably, the mass ratio of the calcium carbide to the aluminum carbide is (4-6):1.

[0008] In some embodiments, the antioxidant is at least one of 2,6-di-tert-butylhydroquinone and 4-tert-butyl-5-methoxycatechol.

[0009] In some embodiments, the interfacial stabilizer is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid;

[0010] Preferably, the mass ratio of the triazine polycarboxylic acid triethanolamine salt to the polyoxyethylene lauryl ether carboxylic acid is 1:(1.5-3).

[0011] In some embodiments, the crystallization promoter is a mixture of triethylamine-borane complex and zirconium dodecylbenzenesulfonate complex;

[0012] Preferably, the mass ratio of the triethylamine-borane complex to the zirconium dodecylbenzenesulfonate complex is 1:1.

[0013] In some embodiments, the coagulant is a mixture of lithium aluminum hydride and lithium chromate;

[0014] Preferably, the mass ratio of the lithium aluminum hydride to the lithium chromate is (2-3):1.

[0015] In some embodiments, the reinforcing agent is a mixture of methacrylic-cage polysilsesquioxane and acrylic-cage polysilsesquioxane;

[0016] Preferably, the mass ratio of the methacrylic cage silsesquioxane to the acrylic-cage polysilsesquioxane is 1:(2-4).

[0017] In some embodiments, the cementitious material is at least one of sulphoaluminate cement and aluminate cement.

[0018] Another embodiment of the present invention further provides a method for preparing the self-expanding prestressed grouting material, comprising the following steps:

[0019] S1, weighing a crystallization accelerator, a coagulant, a reinforcing agent, and a gelling material respectively according to their mass fractions, and mixing them uniformly to obtain a mixed material;

[0020] S2, weighing the self-stress active material, antioxidant, and interface stabilizer respectively according to their mass parts, adding them to the mixed material, stirring and mixing, and preparing the self-expanding prestressed grouting material.

[0021] In some embodiments, in step S2, the stirring and mixing time is 20 to 60 minutes.

[0022] The advantages and beneficial effects of the embodiments of the present invention are as follows:

[0023] (1) In the embodiment of the present invention, calcium carbide and aluminum carbide self-stress active materials are introduced into the grouting material. When the grouting material is added with water and stirred on site, the calcium carbide and aluminum carbide self-stress active materials react with water to generate acetylene gas, thereby causing the grouting material to expand and forming a prestress effect in the cracks, thereby effectively improving the grouting effect.

[0024] (2) The self-stressed active material in the embodiment of the present invention generates a large number of micro-nano bubbles in the grouting material. These micro-nano bubbles act as heterogeneous crystal nuclei and serve as nucleation sites during the hydration process of the grouting material, which can promote the crystal nucleation and growth of the cementitious material, thereby improving the hydration degree of the grouting stone body and the compressive strength.

[0025] (3) The self-stress active material in the present invention will generate a large number of micro-nano bubbles in the grouting material, and the bubble phase and the solid phase will form a large number of solid-gas interfaces, which will increase the interfacial area of ​​the grouting material system and significantly improve the interfacial energy. When the grouting structure is subjected to external impact, a large amount of impact energy is absorbed by the interface, so that the grouting material has better shock resistance and toughness resistance, and can be used stably under harsh tunnel impact.

[0026] (4) The embodiment of the present invention introduces calcium carbide and aluminum carbide self-stress active materials into the grouting material, which can react with water to generate a large amount of calcium hydroxide and aluminum hydroxide alkaline molecules. On the one hand, these alkaline molecules can combine with silicate ions in the cementitious material to form high-strength calcium silicate gel and aluminum silicate gel, thereby enhancing the compressive and tensile strength of the grouting material and improving its durability; on the other hand, these alkaline molecules can react with carbon dioxide in the air to produce carbonization, thereby improving the mechanical strength of the grouting material. DETAILED DESCRIPTION

[0027] The following describes in detail embodiments of the present invention. The embodiments are exemplary and intended to explain the present invention, but are not to be construed as limiting the present invention.

[0028] Where values ​​are described herein as ranges, it should be understood that such disclosure includes disclosure of all possible sub-ranges within that range, as well as specific values ​​falling within that range, regardless of whether a specific value or sub-range is explicitly stated.

[0029] As used herein, the words "comprise," "include," and "includes" and variations thereof mean that additional elements or integers may be included although permitted but not specifically described.

[0030] In this article, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0031] On the one hand, an embodiment of the present invention provides a self-expanding prestressed grouting material, comprising the following components in parts by mass: 12-15 parts of self-stress active material (non-limiting examples: 12 parts, 13 parts, 14 parts, 15 parts, etc.), 1-2 parts of antioxidant (non-limiting examples: 1 part, 2 parts, etc.), 1-2 parts of interface stabilizer (non-limiting examples: 1 part, 2 parts, etc.), 1-2 parts of crystallization promoter (non-limiting examples: 1 part, 2 parts, etc.), 1-3 parts of coagulant (non-limiting examples: 1 part, 2 parts, etc.), 3-5 parts of reinforcing agent (non-limiting examples: 3 parts, 4 parts, 5 parts, etc.), and 100-120 parts of cementitious material (non-limiting examples: 100 parts, 105 parts, 110 parts, 120 parts, etc.).

[0032] In some embodiments, the self-stressed active material is a mixture of calcium carbide (CAS: 75-20-7) and aluminum carbide (CAS: 1299-86-1);

[0033] Preferably, the mass ratio of the calcium carbide to the aluminum carbide is (4-6):1, with non-limiting examples including 4:1, 5:1, and 6:1. The inventors have discovered that if the mass ratio of calcium carbide is too high, excessive gas generation will occur, leading to a loss of mechanical properties of the grouting material. However, if the mass ratio of calcium carbide is too low, insufficient gas generation will occur, resulting in a low expansion ratio and low prestress. Therefore, in the embodiments of the present invention, it is advantageous to control the mass ratio of calcium carbide to aluminum carbide to (4-6):1.

[0034] In some embodiments, the antioxidant is at least one of 2,6-di-tert-butylhydroquinone (CAS: 2444-28-2) and 4-tert-butyl-5-methoxycatechol (CAS: 91352-66-8).

[0035] In some embodiments, the interfacial stabilizer is a mixture of triazine polycarboxylic acid triethanolamine salt (CAS: 80584-92-5) and polyoxyethylene lauryl ether carboxylic acid (CAS: 220622-96-8);

[0036] Preferably, the mass ratio of the triazine polycarboxylic acid triethanolamine salt to the polyoxyethylene lauryl ether carboxylic acid is 1:(1.5-3), non-limiting examples include: 1:1.5, 1:2, 1:3, etc.

[0037] By combining triazine polycarboxylic acid triethanolamine salt with polyoxyethylene lauryl ether carboxylic acid as an interfacial stabilizer, microbubbles can be stably generated, resulting in a better self-expansion effect for the material. The inventors have discovered that if the amount of interfacial stabilizer added is too high, the overall mechanical properties of the grouting material will be impaired; however, if the amount of interfacial stabilizer added is too low, the microbubbles will be difficult to stabilize, resulting in a weaker self-expansion effect. Therefore, in the embodiments of the present invention, the amount of interfacial stabilizer added is controlled to 1-2 parts.

[0038] In some embodiments, the crystallization promoter is a mixture of triethylamine-borane complex (CAS: 1722-26-5) and zirconium dodecylbenzenesulfonate complex (CAS: 109766-35-0);

[0039] Preferably, the mass ratio of the triethylamine-borane complex to the zirconium dodecylbenzenesulfonate complex is 1:1.

[0040] By combining a triethylamine-borane complex with a zirconium dodecylbenzenesulfonate complex as a crystallization accelerator, the hydration and crystallization of a cementitious material can be promoted. The inventors have discovered that if the amount of crystallization accelerator added is too high, the resulting hydrated crystals are numerous but small in size, impairing impact resistance. However, if the amount of crystallization accelerator added is too low, the hydration and crystallization effect is weak, resulting in low mechanical strength. Therefore, in the embodiments of the present invention, it is advantageous to control the amount of crystallization accelerator added to 1-2 parts.

[0041] In some embodiments, the coagulant is a mixture of lithium aluminum hydride (CAS: 16853-85-3) and lithium chromate (CAS: 7789-01-7);

[0042] Preferably, the mass ratio of the lithium aluminum hydride to the lithium chromate is (2-3):1, non-limiting examples include: 2:1, 2.5:1, 3:1, etc.

[0043] By combining lithium aluminum hydride and lithium chromate as a coagulant, the setting of cementitious materials can be accelerated. The inventors have discovered that adding too much coagulant shortens the setting time and reduces the on-site operating window. However, adding too little coagulant results in poor coagulant effects and slows setting. Therefore, the present invention limits the amount of coagulant added to 1-3 parts.

[0044] In some embodiments, the reinforcing agent is a mixture of methacrylic cage silsesquioxane (CAS: 1204591-17-2) and acrylic-cage polysilsesquioxane (CAS: 1620202-27-8);

[0045] Preferably, the mass ratio of the methacrylic cage silsesquioxane to the acrylic cage polysilsesquioxane is 1:(2-4), non-limiting examples include 1:2, 1:3, 1:4, etc.

[0046] By combining methacrylic cage-type silsesquioxane with acrylic cage-type polysilsesquioxane as a reinforcing agent, the mechanical strength of the grouting material can be improved. The inventors have discovered that if the reinforcing agent is added in too high an amount, it will lead to poor dispersion and agglomeration, which will impair the grouting material's flexural and impact resistance. However, if the reinforcing agent is added in too low an amount, the reinforcing effect will be poor, resulting in low mechanical strength. Therefore, in the examples of the present invention, the reinforcing agent is added in an amount of 3-5 parts.

[0047] In some embodiments, the cementitious material is at least one of sulphoaluminate cement and aluminate cement.

[0048] Another embodiment of the present invention further provides a method for preparing the self-expanding prestressed grouting material, comprising the following steps:

[0049] S1, weighing a crystallization accelerator, a coagulant, a reinforcing agent, and a gelling material respectively according to their mass fractions, and mixing them uniformly to obtain a mixed material;

[0050] S2, weighing the self-stress active material, antioxidant, and interface stabilizer respectively according to their mass parts, adding them to the mixed material, stirring and mixing, and preparing the self-expanding prestressed grouting material.

[0051] In some embodiments, in step S2, the stirring and mixing time is 20 to 60 minutes, non-limiting examples include: 20 minutes, 30 minutes, 45 minutes, 50 minutes, 60 minutes, etc.

[0052] The technical solution of the present invention is further described in detail below with reference to specific examples. Unless otherwise specified, the various raw materials used in the examples are conventional commercial products or can be prepared by known methods.

[0053] Example 1

[0054] This embodiment provides a method for preparing a self-expanding prestressed grouting material, comprising the following steps:

[0055] S1, weighing 1 part of a crystallization accelerator, 1 part of a coagulant, 3 parts of a reinforcing agent, and 100 parts of a gelling material respectively by mass, and mixing them uniformly to obtain a mixed material;

[0056] S2. Weigh 12 parts of self-stress active material, 1 part of antioxidant, and 1 part of interface stabilizer respectively according to their mass parts, add them to the mixed material obtained in step S1, and stir and mix them in a dry powder mixer for 30 minutes to obtain a self-expanding prestressed grouting material.

[0057] The self-stress active material in this embodiment is a mixture of calcium carbide and aluminum carbide, and the mass ratio thereof is 5:1;

[0058] The antioxidant in this embodiment is 2,6-di-tert-butylhydroquinone;

[0059] The interfacial stabilizer in this embodiment is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid, and the mass ratio thereof is 1:2;

[0060] The crystallization accelerator in this embodiment is a mixture of triethylamine-borane complex and zirconium dodecylbenzenesulfonate complex, and the mass ratio thereof is 1:1;

[0061] The coagulant in this embodiment is a mixture of lithium aluminum hydride and lithium chromate, and the mass ratio thereof is 2:1;

[0062] The reinforcing agent in this embodiment is a mixture of methacrylic cage-type silsesquioxane and acrylic-cage-type polysilsesquioxane, and the mass ratio thereof is 1:3;

[0063] The cementitious material in this embodiment is sulphoaluminate cement.

[0064] Example 2

[0065] This embodiment provides a method for preparing a self-expanding prestressed grouting material, comprising the following steps:

[0066] S1, weighing 2 parts of crystallization accelerator, 1 part of coagulant, 4 parts of reinforcing agent and 105 parts of gelling material respectively by mass, and mixing them uniformly to obtain a mixed material;

[0067] S2. Weigh 13 parts of self-stress active material, 1 part of antioxidant, and 1 part of interface stabilizer respectively according to their mass parts, add them to the mixed material obtained in step S1, and stir and mix them in a dry powder mixer for 30 minutes to obtain a self-expanding prestressed grouting material.

[0068] The self-stress active material in this embodiment is a mixture of calcium carbide and aluminum carbide, and the mass ratio thereof is 5:1;

[0069] The antioxidant in this embodiment is 4-tert-butyl-5-methoxycatechol;

[0070] The interfacial stabilizer in this embodiment is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid, and the mass ratio thereof is 1:2;

[0071] The crystallization accelerator in this embodiment is a mixture of triethylamine-borane complex and zirconium dodecylbenzenesulfonate complex, and the mass ratio thereof is 1:1;

[0072] The coagulant in this embodiment is a mixture of lithium aluminum hydride and lithium chromate, and the mass ratio thereof is 2:1;

[0073] The reinforcing agent in this embodiment is a mixture of methacrylic cage-type silsesquioxane and acrylic-cage-type polysilsesquioxane, and the mass ratio thereof is 1:3;

[0074] The cementitious material in this embodiment is sulphoaluminate cement.

[0075] Example 3

[0076] This embodiment provides a method for preparing a self-expanding prestressed grouting material, comprising the following steps:

[0077] S1, weighing 1 part of a crystallization accelerator, 2 parts of a coagulant, 4 parts of a reinforcing agent, and 110 parts of a gelling material respectively by mass, and mixing them uniformly to obtain a mixed material;

[0078] S2. Weigh 13 parts of self-stress active material, 2 parts of antioxidant, and 1 part of interface stabilizer respectively according to their mass parts, add them to the mixed material obtained in step S1, and stir and mix them in a dry powder mixer for 30 minutes to obtain a self-expanding prestressed grouting material.

[0079] The self-stress active material in this embodiment is a mixture of calcium carbide and aluminum carbide, and the mass ratio thereof is 5:1;

[0080] The antioxidant in this embodiment is 2,6-di-tert-butylhydroquinone;

[0081] The interfacial stabilizer in this embodiment is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid, and the mass ratio thereof is 1:2;

[0082] The crystallization accelerator in this embodiment is a mixture of triethylamine-borane complex and zirconium dodecylbenzenesulfonate complex, and the mass ratio thereof is 1:1;

[0083] The coagulant in this embodiment is a mixture of lithium aluminum hydride and lithium chromate, and the mass ratio thereof is 2:1;

[0084] The reinforcing agent in this embodiment is a mixture of methacrylic cage-type silsesquioxane and acrylic-cage-type polysilsesquioxane, and the mass ratio thereof is 1:3;

[0085] The cementitious material in this embodiment is aluminate cement.

[0086] Example 4

[0087] This embodiment provides a method for preparing a self-expanding prestressed grouting material, comprising the following steps:

[0088] S1, weighing 2 parts of crystallization accelerator, 2 parts of coagulant, 5 parts of reinforcing agent and 115 parts of gelling material respectively by mass, and mixing them uniformly to obtain a mixed material;

[0089] S2. Weigh 14 parts of self-stress active material, 1 part of antioxidant, and 1 part of interface stabilizer respectively according to their mass parts, add them to the mixed material obtained in step S1, and stir and mix them in a dry powder mixer for 30 minutes to obtain a self-expanding prestressed grouting material.

[0090] The self-stress active material in this embodiment is a mixture of calcium carbide and aluminum carbide, and the mass ratio thereof is 5:1;

[0091] The antioxidant in this embodiment is 2,6-di-tert-butylhydroquinone;

[0092] The interfacial stabilizer in this embodiment is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid, and the mass ratio thereof is 1:2;

[0093] The crystallization accelerator in this embodiment is a mixture of triethylamine-borane complex and zirconium dodecylbenzenesulfonate complex, and the mass ratio thereof is 1:1;

[0094] The coagulant in this embodiment is a mixture of lithium aluminum hydride and lithium chromate, and the mass ratio thereof is 2:1;

[0095] The reinforcing agent in this embodiment is a mixture of methacrylic cage-type silsesquioxane and acrylic-cage-type polysilsesquioxane, and the mass ratio thereof is 1:3;

[0096] The cementitious material in this embodiment is aluminate cement.

[0097] Example 5

[0098] This embodiment provides a method for preparing a self-expanding prestressed grouting material, comprising the following steps:

[0099] S1, weighing 2 parts of crystallization accelerator, 3 parts of coagulant, 5 parts of reinforcing agent and 120 parts of gelling material respectively by mass, and mixing them uniformly to obtain a mixed material;

[0100] S2. Weigh 15 parts of self-stress active material, 2 parts of antioxidant, and 2 parts of interface stabilizer respectively according to their mass parts, add them to the mixed material obtained in step S1, and stir and mix in a dry powder mixer for 30 minutes to obtain a self-expanding prestressed grouting material.

[0101] The self-stress active material in this embodiment is a mixture of calcium carbide and aluminum carbide, and the mass ratio thereof is 5:1;

[0102] The antioxidant in this embodiment is 4-tert-butyl-5-methoxycatechol;

[0103] The interfacial stabilizer in this embodiment is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid, and the mass ratio thereof is 1:2;

[0104] The crystallization accelerator in this embodiment is a mixture of triethylamine-borane complex and zirconium dodecylbenzenesulfonate complex, and the mass ratio thereof is 1:1;

[0105] The coagulant in this embodiment is a mixture of lithium aluminum hydride and lithium chromate, and the mass ratio thereof is 2:1;

[0106] The reinforcing agent in this embodiment is a mixture of methacrylic cage-type silsesquioxane and acrylic-cage-type polysilsesquioxane, and the mass ratio thereof is 1:3;

[0107] The cementitious material in this embodiment is sulphoaluminate cement.

[0108] The performance test of the grouting material prepared in the above embodiment was carried out, and the results are shown in Table 1.

[0109] Table 1

[0110]

[0111]

[0112] As can be seen from Table 1, the embodiments of the present invention can produce a prestressed effect by optimizing the formula composition of the grouting material and introducing calcium carbide and aluminum carbide self-stress active materials, which is beneficial to improving the grouting effect and also improving the mechanical properties of the grouting material.

[0113] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0114] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A self-expanding prestressed grouting material, characterized in that: The invention is composed of the following components in parts by mass: 12-15 parts of self-stress active material, 1-2 parts of antioxidant, 1-2 parts of interface stabilizer, 1-2 parts of crystallization accelerator, 1-3 parts of coagulant, 3-5 parts of reinforcing agent, and 100-120 parts of gelling material; Wherein, the self-stress active material is a mixture of calcium carbide and aluminum carbide in a mass ratio of (4-6):1; The antioxidant is at least one of 2,6-di-tert-butylhydroquinone and 4-tert-butyl-5-methoxycatechol; The interfacial stabilizer is a mixture of triazine polycarboxylic acid triethanolamine salt and polyoxyethylene lauryl ether carboxylic acid in a mass ratio of 1: (1.5-3); The crystallization accelerator is a mixture of a triethylamine-borane complex and a zirconium dodecylbenzenesulfonate complex in a mass ratio of 1:1; The coagulant is a mixture of lithium aluminum hydride and lithium chromate in a mass ratio of (2-3):1; The reinforcing agent is a mixture of methacrylic cage-type silsesquioxane and acrylic-cage-type polysilsesquioxane in a mass ratio of 1:(2-4).

2. The self-expanding prestressed grouting material according to claim 1, characterized in that: The cementitious material is at least one of sulphoaluminate cement and aluminate cement.

3. A method for preparing the self-expanding prestressed grouting material according to claim 1 or 2, characterized in that: The steps include: S1, weighing a crystallization accelerator, a coagulant, a reinforcing agent, and a gelling material respectively according to their mass fractions, and mixing them uniformly to obtain a mixed material; S2, weighing the self-stress active material, antioxidant, and interface stabilizer respectively according to their mass parts, adding them to the mixed material, stirring and mixing, and preparing the self-expanding prestressed grouting material.

4. The method for preparing the self-expanding prestressed grouting material according to claim 3, wherein: In step S2, the stirring and mixing time is 20 to 60 minutes.

Images