High performance cement-silica sol grout and method of making

Abstract

The present application relates to grouting material technical field, specifically to a kind of high-performance cement-silica sol grouting material and its preparation method.The high-performance cement-silica sol grouting material includes A component and B component, the A component includes the following weight parts of raw material: Portland cement 20-50 parts;Water 20-70 parts;Water reducing agent 0.6-3.2 parts;The B component includes the following weight parts of raw material: nano-silica sol 30-60 parts;Solidifying agent 2-10 parts;Inorganic fiber 2-8 parts;Early strength agent 1.2-6 parts, water 10-50 parts.The grouting material prepared by the present application has high strength, fast setting time, low viscosity, good grouting property, strong penetration, good water resistance, excellent impermeability, high retention rate, not easy to wash out, can be injected into small cracks, has high long-term durability, can efficiently complete rock mass water seepage crack and structure cement slurry crack sealing, and has green environmental protection and other advantages.

Description

Technical Field

[0001] This invention relates to the field of grouting technology, specifically to a high-performance cement-silica sol grouting material and its preparation method. Background Technology

[0002] Water glass grout has been used for a long time due to its low price, ease of construction, and good strength. However, the sodium ions in the gel after solidification of water glass grout can dissolve silica, and the volume change of the gel itself leads to poor water resistance and durability, making it unsuitable for permanent engineering projects. Furthermore, existing chemical grouting technologies suffer from low strength and are prone to cracking, limiting the technological development of grouting materials in construction engineering. Tunnel leakage is particularly common. Water leakage is caused by seepage channels formed by fissures in the surrounding rock and cracks created by structural cement grout. However, traditional grouting and plugging materials, such as cement grout or cement-water glass grout, cannot solve the leakage problem. Cement grout has a slow setting time, low retention rate, low utilization rate, and inconsistent cement particle size, making it difficult to plug tiny cracks in the rock mass and structural cement grout. While cement-water glass grout has a short setting time and enhanced permeability, it is also insufficient for grouting cracks under flowing water conditions. In addition, both cement grout and water glass grout are easily washed away by water, leading to unsuccessful sealing. Using traditional polyurethane grouting materials carries the risk of spontaneous combustion and has poor long-term durability. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide a high-performance cement-silica sol grout. This grout has high strength, fast setting time, low viscosity, good injectability, strong permeability, good water resistance, excellent impermeability, high retention rate, and is not easily washed away. It can be injected into micro-cracks, has high long-term durability, and can efficiently seal seepage cracks in rock masses and cement grout cracks in structures. It also has the advantages of being green and environmentally friendly.

[0004] This invention also provides a scientific and reasonable preparation method that is suitable for large-scale production.

[0005] The high-performance cement-silica sol grouting material of the present invention comprises component A and component B, wherein component A comprises the following raw materials in parts by weight: 20-50 parts of silicate cement; 20-70 parts water; Water-reducing agent: 0.6-3.2 parts; Component B comprises the following raw materials in parts by weight: Nano silica sol 30-60 parts; curing agent 2-10 parts; inorganic fiber 2-8 parts; early strength agent 1.2-6 parts; water 10-50 parts; The nano-silica sol is one or more of alkaline nano-silica sol, neutral nano-silica sol, and modified nano-silica sol.

[0006] The alkaline nano-silica sol has a pH of 8.0-10.5, a silica content of 5-40 wt.%, a sodium oxide content of <0.5 wt.%, and the balance being a water dispersant. The particle size is 3-150 nm, and the conductivity is controlled between 2000-10000 μS / cm. Preferably, it is the JN-20G product from Shandong Kehan ​​Silicon Source New Materials Co., Ltd.

[0007] The neutral nano-silica sol has a pH of 7-8.5, a silica content of 5-35 wt.%, a sodium oxide content of <0.2 wt.%, with the remainder being water as a dispersant. The particle size is 3-150 nm, and the conductivity is controlled at 1000-4000 μS / cm. Preferably, it is the KHZ-30 product from Shandong Kehan ​​Silicon Source New Materials Co., Ltd.

[0008] The modified nano-silica sol is prepared by grafting organic polymers or silane coupling agents onto alkaline or neutral silica sol, such as grafted hydroxyl, amide, or vinyl groups, resulting in silica sol-vinyl alcohol graft copolymers, silica sol-acrylamide copolymers, silica sol-vinylpyrrolidone copolymers, silica sol-vinylsilane coupling agent copolymers, silica sol-alkylsilane coupling agent copolymers, silica sol-acyloxysilane coupling agents, silica sol-phenylsilane coupling agents, silica sol-aminosilane coupling agents, silica sol-ureasilane coupling agents, silica sol-thiol silane coupling agents, silica sol-titanium ester coupling agents, silica sol-aluminate coupling agents, etc. The modified nano-silica sol has a pH of 8-11, a silica content of 5-35 wt.%, and a grafted polymer ratio of 0.05-10% of the silica sol. KHM-422G product from Shandong Kehan ​​Silicon Source New Materials Co., Ltd. is preferred.

[0009] The curing agent is one or more of potassium chloride, potassium carbonate, potassium silicate, sodium silicate, potassium bicarbonate, and sodium chloride.

[0010] The inorganic fiber is one or more of glass fiber, alkali-resistant quartz glass fiber, and carbon fiber.

[0011] The early-strength agent is a nucleation early-strength agent, an inorganic-organic nanocomposite material with a CSH nucleus structure. Preferably, it is the ART-CSH nucleation early-strength agent from Jiangsu Aolaite New Material Co., Ltd.

[0012] Compared with traditional inorganic salt and alkanolamine-based early-strength agents, this agent exhibits a more significant early-strength effect and better compatibility with cementitious materials. CSH crystal nuclei can induce cement hydration, lower the activation energy of the hydration reaction, increase the hydration rate, and promote rapid strength development during the hardening period, significantly improving the early strength of cement paste. The characteristics of this early-strength agent are as follows: excellent ultra-early-strength performance; it can significantly improve the early strength of cement paste under normal temperature, low temperature, or hot curing temperature conditions; it can improve the durability of cement paste, and with appropriate dosage, the later strength of the cement paste will not shrink.

[0013] The water-reducing agent is one or both of sodium lignosulfonate and naphthalenesulfonate formaldehyde condensate.

[0014] The preparation method of the high-performance cement-silica sol grouting material of the present invention includes the following steps: Step 1: Weigh the raw materials of each component; Step 2: Add silicate cement, water, and water-reducing agent to a high-speed mixer in sequence. The mixing speed is 1000-1200 r / min, and the mixing time is 3-10 min to obtain component A. Add nano silica sol, curing agent, inorganic fiber, early strength agent, and water to a high-speed mixer in sequence. The mixing speed is 1000-1200 r / min, and the mixing time is 3-10 min to obtain component B.

[0015] Step 3: Add component A and component B obtained in step 2 to a high-speed mixer at a volume ratio of 1:(1-1.5), with a mixing speed of 600-800 r / min and a mixing time of 5-60 s, to obtain high-performance cement-silica sol grouting material.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The grouting material prepared by this invention has high strength, fast setting time, low viscosity, good injectability, strong permeability, good water resistance, excellent impermeability, high retention rate, and is not easily washed away; it can be injected into micro-cracks; it has high long-term durability and can efficiently seal seepage cracks in rock masses and cement grout cracks in structures, and is also environmentally friendly. It has high practical value and good application prospects in crack seepage prevention, seepage prevention and water stopping of underground foundations, seepage prevention and reinforcement of underground engineering and tunnel engineering, dam seepage prevention and reinforcement, groundwater protection and seepage prevention, mining backfilling and other projects.

[0017] (2) The early-strength agent used in this invention is a nucleus-based early-strength agent, an inorganic-organic nanocomposite material with a CSH nucleus structure. Compared with traditional inorganic salts and alkanolamines, it has a more significant early-strength effect and better compatibility with cementitious materials. The CSH nuclei can induce cement hydration, reduce the activation energy of cement hydration reaction, increase the hydration reaction rate, promote rapid strength development during the hardening period, and significantly improve the early strength of cement paste within 24 hours. This early-strength agent has no side effects on the strength of cement paste and does not affect the durability of cement paste. Its characteristics are as follows: excellent ultra-early-strength performance, which can significantly improve the early strength of cement paste under normal temperature, low temperature or hot curing temperature conditions; it can improve the durability of cement paste, and the later strength of cement paste will not shrink if the dosage is appropriate; it shortens or even eliminates the steam curing process, saving energy and reducing consumption. Detailed Implementation

[0018] The present invention will be further described below with reference to the embodiments, but the scope of protection of the present invention is not limited thereto.

[0019] Unless otherwise specified, all raw materials used in the examples were commercially available.

[0020] KHZ-30, neutral nano-silica sol, Shandong Kehan ​​Silicon Source New Material Co., Ltd.; Carbon fiber, ultra-short carbon fiber, Shandong Jianhui Chemical Co., Ltd.; JN-20G, alkaline nano silica sol, Shandong Kehan ​​Silicon Source New Material Co., Ltd.; KHM-422G, modified nano-silica sol, Shandong Kehan ​​Silicon Source New Material Co., Ltd.; CSH early strength agent, ART-CSH nucleation early strength agent, Jiangsu Aolaite New Material Co., Ltd.; Sodium lignosulfonate, water-reducing agent, Jiangsu Aolaite New Material Co., Ltd.; Water glass, modulus 3.3, Baume degree 42, Shandong Kehan ​​Silicon Source New Material Co., Ltd.; Polycarboxylate superplasticizer, TD-JSS, Tuoda New Material Technology Industry Group Co., Ltd.; Concrete early strength agent, TD-ZQJ77, Tuoda New Material Technology Industry Group Co., Ltd.

[0021] Example 1

[0022] First, add 352.5 kg of silicate 425# cement, 375 kg of water, and 22.5 kg of water-reducing agent sodium lignosulfonate to a high-speed mixer. Mix at 1000 r / min for 7 min to obtain component A. Then, add 397.5 kg of KHZ-30 silica sol, 4.2 kg of sodium chloride, 7 kg of potassium chloride, 3.05 kg of potassium silicate, 6 kg of potassium bicarbonate, 15 kg of carbon fiber, 27 kg of CSH early strength agent, and 290.25 kg of water to the high-speed mixer in sequence. Mix at 1000 r / min for 3 min to obtain component B.

[0023] 750 kg of component A and 750 kg of component B were poured into a high-speed mixer at a 1:1 mass ratio and mixed at 800 r / min for 30 s to obtain ordinary high-efficiency cement-silica sol grouting material.

[0024] Example 2:

[0025] First, add 400 kg of silicate 425# cement, 568 kg of water, and 32 kg of water-reducing agent sodium lignosulfonate to a high-speed mixer. Mix at 1000 r / min for 7 min to obtain component A. Then, add 500 kg of KHM-422G silica sol, 21 kg of sodium chloride, 22 kg of potassium chloride, 19 kg of potassium bicarbonate, 24 kg of carbon fiber, 36 kg of CSH early strength agent, and 378 kg of water to the high-speed mixer in sequence. Mix at 1000 r / min for 3 min to obtain component B.

[0026] 1000 kg of component A and 1000 kg of component B were poured into a high-speed mixer at a 1:1 mass ratio and mixed at a speed of 800 r / min for 30 s to obtain modified high-efficiency cement-silica sol grouting material.

[0027] Example 3:

[0028] First, add 400 kg of silicate 425# cement, 374.4 kg of water, and 25.6 kg of water-reducing agent sodium lignosulfonate to a high-speed mixer. Mix at 1000 r / min for 8 min to obtain component A. Then, add 448 kg of JN-20G silica sol, 12.6 kg of sodium chloride, 24.7 kg of potassium carbonate, 18 kg of potassium silicate, 3.9 kg of potassium bicarbonate, 17.6 kg of carbon fiber, 44 kg of CSH early strength agent, and 231.2 kg of water to the high-speed mixer in sequence. Mix at 1000 r / min for 3 min to obtain component B.

[0029] 800 kg of component A and 800 kg of component B were poured into a high-speed mixer at a 1:1 mass ratio and mixed at 800 r / min for 30 s to obtain early-strength, high-efficiency cement-silica sol grouting material.

[0030] Comparative Example 1: First, add 280 kg of silicate 425# cement and 280 kg of water to a high-speed mixer, mix at 1000 r / min for 7 min to obtain component A; then add 280 kg of water glass with a modulus of 3.3 and a Baume degree of 42 and 280 kg of water to the high-speed mixer, mix at 1000 r / min for 3 min to obtain component B.

[0031] 560 kg of component A and 560 kg of component B were poured into a high-speed mixer at a 1:1 mass ratio and mixed at 800 r / min for 30 s to obtain cement-water glass grout.

[0032] Comparative Example 2: First, add 352.5 kg of silicate 425# cement, 375 kg of water, and 22.5 kg of polycarboxylate superplasticizer to a high-speed mixer. Mix at 1000 r / min for 7 min to obtain component A. Then, add 397.5 kg of KHZ-30 silica sol, 4.2 kg of sodium chloride, 7 kg of potassium chloride, 3.05 kg of potassium silicate, 6 kg of potassium bicarbonate, 15 kg of carbon fiber, 27 kg of CSH early strength agent, and 290.25 kg of water to the high-speed mixer in sequence. Mix at 1000 r / min for 3 min to obtain component B.

[0033] 750 kg of component A and 750 kg of component B were poured into a high-speed mixer at a 1:1 mass ratio, and the mixing speed was 800 r / min for 30 s to obtain a comparative ordinary cement-silica sol grout.

[0034] Comparative Example 3: First, add 400 kg of silicate 425# cement, 374.4 kg of water, and 25.6 kg of water-reducing agent sodium lignosulfonate to a high-speed mixer. Mix at 1000 r / min for 8 min to obtain component A. Then, add 448 kg of JN-20G silica sol, 12.6 kg of sodium chloride, 24.7 kg of potassium carbonate, 18 kg of potassium silicate, 3.9 kg of potassium bicarbonate, 17.6 kg of carbon fiber, 44 kg of concrete early strength agent, and 231.2 kg of water to the high-speed mixer in sequence. Mix at 1000 r / min for 3 min to obtain component B.

[0035] 800 kg of component A and 800 kg of component B were poured into a high-speed mixer at a 1:1 mass ratio and mixed at 800 r / min for 30 s to obtain a comparative early-strength and high-efficiency cement-silica sol grouting material.

[0036] According to the requirements of the JC / T2536-2019 standard for cement-water glass grouting materials: Example 1: The setting time is approximately 120 seconds; the compressive strength is 3.2 MPa at 1 day, 6.4 MPa at 3 days, and 14.6 MPa at 28 days; the flexural strength is 1.2 MPa at 3 days and 1.8 MPa at 28 days; the impermeability pressure is 1.6 MPa; the compressive strength loss rate in the freeze-thaw resistance is 15%, and the mass loss rate is 3%. Comparative Example 1 had a setting time of approximately 118 s, compressive strength of 2.8 MPa at 1 day, 5.2 MPa at 3 days, and 10.5 MPa at 28 days; flexural strength of 0.8 MPa at 3 days and 1.2 MPa at 28 days; impermeability pressure of 1.0 MPa; and compressive strength loss rate of 22% and mass loss rate of 4.5% in its freeze-thaw resistance. Example 2: The setting time was approximately 62 seconds; the compressive strength was 4.2 MPa at 1 day, 9.4 MPa at 3 days, and 24.3 MPa at 28 days; the flexural strength was 2.5 MPa at 3 days and 3.7 MPa at 28 days; the impermeability pressure was 1.4 MPa; the compressive strength loss rate in the freeze-thaw resistance was 14%, and the mass loss rate was 3%. Comparative Example 2 had a setting time of approximately 106 s, compressive strength of 3.5 MPa at 1 day, 7.4 MPa at 3 days, and 19.8 MPa at 28 days; flexural strength of 1.6 MPa at 3 days and 2.1 MPa at 28 days; impermeability pressure of 1.1 MPa; and compressive strength loss rate of 21% and mass loss rate of 3.3% in its freeze-thaw resistance. Example 3: The setting time was approximately 57 seconds; the compressive strength was 5.6 MPa at 1 day, 15.6 MPa at 3 days, and 30.2 MPa at 28 days; the flexural strength was 4.9 MPa at 3 days and 6.0 MPa at 28 days; the impermeability pressure was 1.9 MPa; the compressive strength loss rate in the freeze-thaw resistance was 12%, and the mass loss rate was 1.5%. Comparative Example 3 had a setting time of approximately 114 s, compressive strength of 3.7 MPa at 1 day, 6.8 MPa at 3 days, and 15.7 MPa at 28 days; flexural strength of 2.3 MPa at 3 days and 3.9 MPa at 28 days; impermeability pressure of 1.4 MPa; and compressive strength loss of 23% and mass loss of 3.5% in its freeze-thaw resistance.

Claims

1. A high-performance cement-silica sol grout, characterized in that, It includes component A and component B, wherein component A comprises the following raw materials in parts by weight: 20-50 parts of silicate cement; Water 20-70 parts; water-reducing agent 0.6-3.2 parts; Component B comprises the following raw materials in parts by weight: Nano silica sol 30-60 parts; curing agent 2-10 parts; inorganic fiber 2-8 parts; early strength agent 1.2-6 parts; water 10-50 parts; The nano-silica sol is one or more of alkaline nano-silica sol, neutral nano-silica sol, and modified nano-silica sol; the modified nano-silica sol is prepared by grafting an organic polymer or a silane coupling agent onto alkaline or neutral silica sol, the modified nano-silica sol has a pH of 8-11, a silica content of 5-35 wt.%, and a grafted polymer ratio of 0.05-10% of the silica sol; The curing agent is one or more of potassium chloride, potassium carbonate, potassium silicate, sodium silicate, potassium bicarbonate, and sodium chloride. The early strength agent is a nucleation early strength agent, which is an inorganic-organic nanocomposite material with a CSH nucleation structure. The grouting material is obtained through the following steps: Mix component A and component B at a volume ratio of 1:(1~1.5), with a mixing speed of 600~800 r / min and a mixing time of 5s~60s.

2. The high-performance cement-silica sol grouting material according to claim 1, characterized in that, The alkaline nano-silica sol has a pH of 8.0-10.5, a silica content of 5-40 wt.%, a sodium oxide content of <0.5 wt.%, and the balance being a water dispersant. The particle size is 3-150 nm, and the conductivity is controlled at 2000-10000 μs / cm.

3. The high-performance cement-silica sol grouting material according to claim 1, characterized in that, The neutral nano-silica sol has a pH of 7-8.5, a silica content of 5-35 wt.%, a sodium oxide content of <0.2 wt.%, and the remainder is water as a dispersant. The particle size is 3-150 nm, and the conductivity is controlled at 1000-4000 μs / cm.

4. The high-performance cement-silica sol grouting material according to claim 1, characterized in that, The inorganic fiber is one or more of glass fiber, alkali-resistant quartz glass fiber, and carbon fiber.

5. The high-performance cement-silica sol grouting material according to claim 1, characterized in that, The water-reducing agent is either sodium lignosulfonate or naphthalenesulfonate formaldehyde condensate.

6. A method for preparing the high-performance cement-silica sol grout according to any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Weigh the raw materials of each component; Step 2: Add silicate cement, water, and water-reducing agent to a high-speed mixer in sequence, with a mixing speed of 1000-1200 r / min and a mixing time of 3-10 min to obtain component A; add nano silica sol, curing agent, inorganic fiber, early strength agent, and water to the high-speed mixer in sequence, with a mixing speed of 1000-1200 r / min and a mixing time of 3-10 min to obtain component B; Step 3: Add component A and component B obtained in step 2 to a high-speed mixer at a volume ratio of 1:(1-1.5), with a mixing speed of 600-800 r / min and a mixing time of 5-60 s, to obtain high-performance cement-silica sol grouting material.