High-performance subsea tunnel damage repairing material

Abstract

The invention aims to provide the high-performance subsea tunnel damage repairing material, and the repairing material has excellent bonding strength, erosion resistance, water resistance, mechanical property and durability, and can effectively repair damage and cracks generated in a tunnel. Comprising the following components in parts by weight: 60-73 parts of superfine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of a CSA expanding agent, 8-12 parts of mineral powder, 8-12 parts of fly ash microspheres, 40 parts of 20-40-mesh quartz sand, 10 parts of 40-70-mesh quartz sand, 30 parts of 70-110-mesh quartz sand, 0.1-0.2 part of a defoaming agent, 25-27 parts of water, 1.5 parts of a water reducing agent, 1-3 parts of nano silicon dioxide, 8-12 parts of PTB emulsion and 1-2 parts of butadiene-styrene rubber powder. When tunnel cracks and damaged parts to be repaired are filled with the crack repairing material, the operation time does not exceed 30 min, the curing time is about 12 h, and the crack repairing material is suitable for operation in a humid environment.

Description

Technical Field

[0001] The invention relates to a tunnel crack quick repair material in a humid environment and belongs to the technical field of building repair. Background Art

[0002] China has the largest number of tunnels in the world, and most of the tunnels in China are still operating under the most complex environmental conditions. At present, we have entered a period of equal emphasis on construction and maintenance. As more and more highway, subway and other tunnels reach the end of their specific service life, the incidence of tunnel diseases caused by external forces, deterioration of lining materials and voids behind the lining is gradually increasing. A survey of nearly 50 railway lines in China showed that there were problems in more than 500 railway tunnels and 16 highway tunnels, of which more than 68% had cracks in the tunnel lining. Cracks in the tunnel lining and cracks in the concrete may cause damage to the local or even the entire structure, have a serious impact on train operation, and may also cause catastrophic accidents, threatening life and property.

[0003] In engineering, concrete is a commonly used building material. However, most concrete materials have the characteristics of poor crack resistance, low bonding strength, and poor toughness. With the rapid development of the civil engineering industry, the requirements for various performance indicators of building materials are becoming higher and higher. In particular, the concrete structures of operating tunnels will be damaged and cracked due to improper transportation and harsh environments. Many structures need to be repaired, so concrete crack repair materials have been widely developed. In order to adapt to the complex underground engineering environment, improving the construction performance, mechanical properties, bonding properties and erosion resistance of repair materials has become the focus of current research. These properties can be improved by adding admixtures and inorganic mineral materials. Summary of the invention

[0004] The purpose of the present invention is to provide a rapid repair material with high strength and low shrinkage in the early stage, which has excellent bonding strength and mechanical properties to meet the strength requirements of the matrix itself, and has excellent durability, corrosion resistance, and water resistance, and can effectively repair cracks generated during the use of tunnels and can be used in different environments;

[0005] In order to achieve the above object, the technical solution proposed by the present invention is: a high-performance repair material, characterized in that it includes the following groups in parts by weight:

[0006] 60-73 parts of ultrafine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of CSA expansion agent, 8-12 parts of mineral powder, 8-12 parts of fly ash microspheres, 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, 30 parts of 70-110 mesh quartz sand, 0.1-0.2 parts of defoaming agent and 25-27 parts of water, 1.5 parts of water reducer, 1-3 parts of nano silica, 8-12 parts of PTB emulsion, 1-2 parts of styrene-butadiene rubber powder.

[0007] The preparation process of the high performance repair material is as follows:

[0008] (i) 60-73 parts of ultrafine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of CSA expansion agent, 1-2 parts of styrene-butadiene rubber powder, 8-12 parts of mineral powder and 8-12 parts of fly ash microspheres are mixed uniformly;

[0009] (ii) 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, and 30 parts of 70-110 mesh quartz sand were mixed evenly;

[0010] (iii) mixing the mixture obtained in step (i) with the mixture obtained in step (i);

[0011] (iv) dissolving 1.5 parts of a water reducing agent and 1 to 3 parts of nano-silicon dioxide in 25 to 27 parts of water;

[0012] (v) mixing the mixture obtained in step (iv) and the mixture obtained in step (iii) uniformly;

[0013] (vi) mixing the mixture obtained in step (v) and 8-12 parts of PTB emulsion;

[0014] (vii) mixing the mixture obtained in step (vi) and 0.1-0.2 parts of a defoaming agent to obtain a quick repair material;

[0015] A further design of the above technical solution is as follows: the ultrafine cement is 800 mesh ultrafine cement;

[0016] The sulphoaluminate cement is R.SAC42.5;

[0017] The CSA expansion agent is a Type II CSA expansion agent produced by Polar Bear Company;

[0018] The defoamer is an organosilicon defoamer;

[0019] The 20-110 mesh quartz sand is white quartz sand;

[0020] The mineral powder is S95 mineral powder;

[0021] The fly ash microbeads are 1250 mesh microbeads;

[0022] The water reducer is Sika polycarboxylate water reducer;

[0023] The nano silicon dioxide is 20 nanometers SIO2;

[0024] The PTB emulsion is a vinyl chloride-ethylene-vinyl ester terpolymer emulsion;

[0025] The styrene butadiene rubber powder is PSB150 styrene butadiene rubber powder;

[0026] When the repair material is filled into the cracks or damaged parts of the tunnel to be repaired, the operation time does not exceed 30 minutes, the curing time is about 12 hours, and it is maintained in a normal temperature and humid environment. The cracks are relatively wide cracks of about 3 mm; the damaged parts are any parts where the tunnel lining has fallen off or has missing corners.

[0027] Compared with the prior art, the present invention has the following advantages and beneficial effects: the present invention adopts 800 mesh ultrafine cement, sulphoaluminate cement and CSA expansion agent, and the sulphoaluminate cement and the expansion agent provide sulfate ions to form a cement system with high early strength, small shrinkage and controllable initial setting time.

[0028] The cement system has good permeability and fluidity under the action of 1.5% polycarboxylate water reducer, has extremely low water bleeding rate, can exert greater strength in the early stage and meet the construction time required; by adding 20-110 mesh quartz sand to fill the pore structure in the cement hydration process, the density of the cement material is increased; on the other hand, it acts as a skeleton of the cement paste to reduce shrinkage and increase strength;

[0029] Adding mineral powder to the cement system can significantly improve the durability and crack resistance of cement materials, but it will increase the standard consistency water requirement of cement paste. Fly ash microspheres can significantly improve cement fluidity. The use of a system with complementary performance of mineral powder and fly ash microspheres can make cement have excellent performance under the action of the two materials while maintaining good fluidity;

[0030] The addition of rubber powder can significantly reduce the bleeding rate of cement, enhance the bonding performance, impermeability and crack resistance of the material. When used with PTB emulsion, it can obtain excellent bonding strength with a small amount of emulsion, and has excellent water retention. It has better performance than conventional single emulsion and saves costs;

[0031] The addition of nano-silica can be combined with sulphoaluminate cement in the cement system to control the cement consistency and setting time to achieve controllable repair materials. Nano-silica will fill the pore structure of cement to reduce the transmission channels of water or other harmful ions, and significantly increase the material's impermeability and corrosion resistance. At the same time, nano-silica has extremely strong activity. When the above materials are combined, on the one hand, it can significantly alleviate the shrinkage caused by cement and nano-silica, and at the same time, significant strength performance can be obtained in the early stage of material hydration. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with specific embodiments;

[0033] Embodiment 1;

[0034] 60-73 parts of ultrafine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of CSA expansion agent, 8-12 parts of mineral powder, 8-12 parts of fly ash microspheres, 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, 30 parts of 70-110 mesh quartz sand, 0.1-0.2 parts of defoamer and 25-27 parts of water, 1.5 parts of water reducer, 1-3 parts of nano-silicon dioxide, 8-12 parts of PTB emulsion, 1-2 parts of styrene-butadiene rubber powder;

[0035] The preparation process of the crack repair material is as follows:

[0036] (i) 60 parts of ultrafine cement, 8 parts of sulphoaluminate cement, 8 parts of CSA expansion agent, 1-2 parts of rubber powder, 12 parts of mineral powder and 12 parts of fly ash microspheres are mixed uniformly;

[0037] (ii) 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, and 30 parts of 70-110 mesh quartz sand were mixed evenly;

[0038] (iii) mixing the mixture obtained in step (i) with the mixture obtained in step (i);

[0039] (iv) dissolving 1.5 parts of a water reducing agent and 1 to 3 parts of nano-silicon dioxide in 26 parts of water;

[0040] (v) mixing the mixture obtained in step (iv) and the mixture obtained in step (iii) uniformly;

[0041] (vi) mixing the mixture obtained in step (v) and 8-12 parts of PTB emulsion;

[0042] (vii) mixing the mixture obtained in step (vi) and 0.1-0.2 parts of a defoaming agent to obtain a quick repair material;

[0043] When the crack repair material is filled into the tunnel cracks or missing blocks to be repaired, the operation time does not exceed 30 minutes, the curing time is about 12 hours, and it is cured in a normal temperature and humid environment. The cracks are relatively wide cracks of about 3 mm.

[0044] The repair material of this embodiment adopts the slot repair method when repairing cracked lining, and then injects the repair material into the crack and smoothes it, and waits for 24 hours for the repair material to solidify before the repair is completed. In a humid environment, an indoor simulated crack repair test was carried out, and the strength was measured to be 38MPa at a curing age of 7d, and the strength was measured to be 50.3MPa at 28d.

[0045] Embodiment 2:

[0046] 60-73 parts of ultrafine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of CSA expansion agent, 8-12 parts of mineral powder, 8-12 parts of fly ash microspheres, 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, 30 parts of 70-110 mesh quartz sand, 0.1-0.2 parts of defoamer and 25-27 parts of water, 1.5 parts of water reducer, 1-3 parts of nano-silicon dioxide, 8-12 parts of PTB emulsion, 1-2 parts of styrene-butadiene rubber powder;

[0047] The preparation process of the high performance repair material is as follows:

[0048] (i) 60 parts of ultrafine cement, 8 parts of sulphoaluminate cement, 8 parts of CSA expansion agent, 1-2 parts of rubber powder, 12 parts of mineral powder and 12 parts of fly ash microspheres are mixed uniformly;

[0049] (ii) 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, and 30 parts of 70-110 mesh quartz sand were mixed evenly;

[0050] (iii) mixing the mixture obtained in step (i) with the mixture obtained in step (i);

[0051] (iv) dissolving 1.5 parts of a water reducing agent and 1 to 3 parts of nano-silicon dioxide in 26 parts of water;

[0052] (v) mixing the mixture obtained in step (iv) and the mixture obtained in step (iii) uniformly;

[0053] (vi) mixing the mixture obtained in step (v) and 8-12 parts of PTB emulsion;

[0054] (vii) mixing the mixture obtained in step (vi) and 0.1-0.2 parts of a defoaming agent to obtain a quick repair material;

[0055] When the high-performance repair material is filled into the cracks or missing blocks of the tunnel to be repaired, the operation time does not exceed 30 minutes, the curing time is about 12 hours, and it is cured in a normal temperature and humid environment. The cracks are relatively wide cracks of about 3 mm.

[0056] The repair material of this embodiment adopts the slot repair method when repairing cracked lining, and then injects the repair material into the crack and smoothes it, and waits for 24 hours for the repair material to solidify before the repair is completed. In a humid environment, an indoor simulated crack repair test was carried out, and the strength was measured to be 38MPa at a curing age of 7d, and the strength was measured to be 51.2MPa at 28d.

[0057] Embodiment three;

[0058] The repair material of this embodiment includes the following components: 60-73 parts of ultrafine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of CSA expansion agent, 8-12 parts of mineral powder, 8-12 parts of fly ash microspheres, 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, 30 parts of 70-110 mesh quartz sand, 0.1-0.2 parts of defoamer and 25-27 parts of water, 1.5 parts of water reducing agent, 1-3 parts of nano-silicon dioxide, 8-12 parts of PTB emulsion, and 1-2 parts of styrene-butadiene rubber powder;

[0059] test;

[0060] The ultrafine cement used in the high-performance repair material of this test case can have better penetration and achieve higher strength at an early stage;

[0061] Sulphoaluminate cement provides a certain amount of aluminum phase for the formation of expansion products during cement hydration, and also promotes the early hydration process of cement and enhances durability.

[0062] High-efficiency CSA expansion agent greatly reduces the shrinkage problem caused by cement itself and nano-silicon dioxide; fly ash microspheres and mineral powder can achieve complementary performance, providing strength while fly ash microspheres reduce fluidity loss caused by mineral powder;

[0063] The addition of rubber powder can significantly enhance the water retention of the material, reduce plastic shrinkage, and enhance bonding strength; the addition of nano-silicon dioxide can increase the density of the material, improve durability and corrosion resistance, and achieve satisfactory strength at an early stage.

[0064] The nano-silicon dioxide used in this example is silicon dioxide particles with a diameter of 20 nanometers;

[0065] The quartz sand used in this example is 20-110 mesh graded quartz sand, which forms a skeleton structure inside the material, increasing the strength while reducing the shrinkage of the material itself;

[0066] The polymer emulsion used in this example is a terpolymer emulsion of vinyl chloride, ethylene and vinyl ester, and its performance indicators are shown in Table 2;

[0067] The performance indexes of the ultrafine cement used in this embodiment are shown in Table 1 below;

[0068] Table 1 Main components of Portland cement;

[0069] Table 2 Main components of PTB emulsion;

[0070] The defoamer used in this test example is a silicone defoamer;

[0071] In this test example, the amount of vinyl chloride, ethylene, vinyl ester terpolymer emulsion, rubber powder and nano-silicon dioxide was obtained by adding the content of silicate cement as the standard;

[0072] In this test example, sulphoaluminate cement, CSA expansion agent, mineral powder and fly ash microspheres were obtained by replacing part of the silicate cement with the silicate cement content as the standard. The experimental mix ratio of the repair material is shown in Table 3;

[0073] Table 3 Grouting material mix design;

[0074] The mechanical properties test was carried out using the repair materials with the ratio described in Table 3, and the experimental results were tested. The results are as follows:

[0075] Macro-mechanical properties test:

[0076] Nano-silicon dioxide has a small particle size and a large specific surface area, and has a very high volcanic ash effect. It has a nucleation effect: the high specific surface area and high activity provide abundant nucleation sites for cement hydration products. It significantly accelerates the early hydration reaction rate of cement, promotes the generation and growth of early hydration products, so that the cement paste can quickly form a relatively dense structure in the early stage, greatly improving the early strength of cement; the addition of glue powder will significantly improve the water retention of the repair material, and rely on the later film-forming properties to improve the durability and erosion resistance of the material; in the process of cement hydration, with the formation of dicalcium silicate and tricalcium silicate, a part of calcium hydroxide will also be produced. The participation of nano-silicon dioxide will absorb calcium hydroxide to form CSH gel to enhance the microstructure of cement-based materials and reduce the adverse effects of calcium hydroxide on materials. Nano-silicon dioxide can fill the pores between cement particles and cement paste, improve density, and help improve strength. However, the excessive addition of nano-silica, due to the large specific surface area and strong water absorption capacity of these powders, hinders the hydration process, and its hydration reaction is incomplete, reducing the amount of hydrate generated, making the structure very loose and reducing the strength. The data changes are shown in Table 4.

[0077] Table 4 Curing age of 7d and 28d;

[0078] The above test examples demonstrate the high performance repair material of the present invention.

[0079] The present invention is described in detail above, and specific examples are used herein to illustrate the embodiments of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, the actual operation may be slightly different, and the content of this specification should not be understood as limiting the use of the present invention.

Claims

1. A high-performance submarine tunnel damage repair material, characterized in that: The composition comprises the following components in parts by weight: 60-73 parts of ultrafine cement, 5-8 parts of sulphoaluminate cement, 6-8 parts of CSA expansion agent, 8-12 parts of mineral powder, 8-12 parts of fly ash microspheres, 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, 30 parts of 70-110 mesh quartz sand, 0.1-0.2 parts of defoamer and 25-27 parts of water, 1.5 parts of water reducer, 1-3 parts of nano-silicon dioxide, 8-12 parts of PTB emulsion, 1-2 parts of styrene-butadiene rubber powder; The preparation process of the crack repair material is as follows: (i) 60 parts of ultrafine cement, 8 parts of sulphoaluminate cement, 8 parts of CSA expansion agent, 1-2 parts of rubber powder, 12 parts of mineral powder and 12 parts of fly ash microspheres are mixed uniformly; (ii) 40 parts of 20-40 mesh quartz sand, 10 parts of 40-70 mesh quartz sand, and 30 parts of 70-110 mesh quartz sand were mixed evenly; (iii) mixing the mixture obtained in step (i) with the mixture obtained in step (i); (iv) dissolving 1.5 parts of a water reducing agent and 1 to 33 parts of nano-silicon dioxide in 26 parts of water; (v) mixing the mixture obtained in step (iv) and the mixture obtained in step (iii) uniformly; (vi) mixing the mixture obtained in step (v) and 8-12 parts of PTB emulsion; (vii) The mixture obtained in step (vi) is mixed evenly with 0.1-0.2 parts of a defoaming agent to obtain a quick repair material.

2. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The ultrafine cement model is 800 mesh ultrafine cement.

3. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The sulphoaluminate cement used is R.SAC42.

5.

4. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The expansion agent is CSA expansion agent, which is type II CSA expansion agent produced by Polar Bear Company.

5. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The defoamer is an organosilicon defoamer.

6. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The 20-110 mesh quartz sand is white quartz sand.

7. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The mineral powder is S95 mineral powder, and the nano-silicon dioxide is 20 nanometer hydrophilic nano-silicon dioxide.

8. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The fly ash microbeads are 1250 mesh ultrafine fly ash microbeads, and the styrene butadiene rubber powder is PSB150 styrene butadiene rubber.

9. The high-performance submarine tunnel damage repair material according to claim 1 is characterized in that: The water reducer is Sika polycarboxylic acid water reducer, and the PTB emulsion is vinyl chloride-ethylene-vinyl ester terpolymer emulsion.

10. The high performance submarine tunnel damage repair material according to any one of claims 1 to 10, characterized in that: When the high-performance submarine tunnel damage repair material is filled into the cracks or damaged parts of the tunnel to be repaired, the operation time does not exceed 30 minutes, and the curing time is about 12 hours, which is suitable for operation in a humid environment.

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