Cement-based grouting material and its application and grouting method

Abstract

The present invention provides a cement-based grouting material, which relates to the technical field of building materials. The cement-based grouting material provided by the present invention comprises independently packaged modified cement-based slurry and admixture slurry; the modified cement-based slurry comprises cement, a water reducer and water; the admixture slurry comprises agglomerating agent, a water reducer and water. The present invention improves the performance of cement by adding a water reducer to cement; at the same time, by separately configuring the agglomerating agent, the water reducer and the water into an admixture slurry, an ideal flow effect is achieved; by independently packaging the admixture slurry and the modified cement-based slurry, and then mixing them during grouting, the purpose of more accurately controlling the setting time of the grouting material and enhancing the short-term strength is achieved. The results of the embodiments show that the cement-based grouting material provided by the present invention has the performance of short final setting time and high short-term compressive strength.

Description

Technical Field

[0001] The invention belongs to the technical field of building materials, and particularly relates to a cement-based grouting material and an application and a grouting method thereof. Background Art

[0002] In recent years, with the increasing demand for underground transportation projects in various cities, the length of operating subway lines has experienced explosive growth, posing new challenges to the structural safety management of these structures. Due to the cyclical vibration of subway trains and uneven settlement of tunnel structures, operating subway tunnels are experiencing problems such as ballast delamination, cracking, water leakage, mud, and sand release. Grouting is the conventional treatment method for these problems.

[0003] However, due to the short construction window period (2 to 3 hours) for the treatment of defects in operating subway tunnels, discontinuous work points, and decreased strength and impermeability under vibration environments, this field has put forward new requirements for the working performance, setting time and early strength of cement-based grouting materials: it must be injectable within 30 minutes (that is, the initial setting time of single-liquid slurry is greater than 30 minutes); final setting must be achieved within 1.5 hours after the completion of grouting; and the strength must be increased to more than 10 MPa within 2 hours after the completion of grouting.

[0004] Currently, the commonly used cement-based grouting materials on the market include cement-water glass two-liquid slurry, single-liquid slurry with liquid alkali-free quick-setting agent, etc. Among them, cement-water glass two-liquid slurry can achieve better fluidity and shorter setting time, but its short-term compressive strength is low; single-liquid slurry with liquid alkali-free quick-setting agent has higher short-term compressive strength, but longer final setting time. Summary of the Invention

[0005] The object of the present invention is to provide a cement-based grouting material and its application and grouting method. The cement-based grouting material provided by the present invention has the effects of short setting time and high short-term compressive strength.

[0006] In order to achieve the purpose of the present invention, the present invention provides the following technical solutions:

[0007] A cement-based grouting material, comprising independently packaged modified cement-based slurry and admixture slurry;

[0008] The modified cement-based slurry includes cement, a water-reducing agent and water;

[0009] The admixture slurry includes agglomerating agent, water reducing agent and water.

[0010] Preferably, the mass ratio of the modified cement-based slurry to the admixture slurry is 1:0.35-0.4.

[0011] Preferably, the mass ratio of cement, water reducer and water in the modified cement-based slurry is 100:0.33~1:20~40.

[0012] Preferably, the mass ratio of the agglomerating agent, the water reducing agent and the water in the admixture slurry is 100:0.2-0.5:33-40.

[0013] Preferably, the admixture slurry further includes a retarder; the mass of the retarder does not exceed 0.35% of the mass of the agglomerator.

[0014] Preferably, the cement is ordinary Portland cement.

[0015] Preferably, the water reducer in the modified cement-based slurry and the admixture slurry is a polycarboxylate water reducer.

[0016] Preferably, the agglomerating agent is SC-one agglomerating agent.

[0017] The present invention also provides the use of the cement-based grouting material in treating diseases of an operating subway tunnel.

[0018] The present invention also provides a grouting method, comprising the following steps:

[0019] The double-liquid grouting method is used to grout the depleted area with the modified cement-based slurry and admixture slurry in the cement-based grouting material of the above technical solution.

[0020] The present invention provides a cement-based grouting material, comprising independently packaged modified cement-based slurry and admixture slurry; the modified cement-based slurry comprises cement, a water reducer and water; the admixture slurry comprises a binder, a water reducer and water. The present invention improves the performance of cement by adding a water reducer to cement; at the same time, by separately configuring the binder, the water reducer and water into an admixture slurry, it achieves an ideal flow effect; by independently packaging the admixture slurry and the modified cement-based slurry and then mixing them during grouting, the purpose of more accurately controlling the final setting time of the grouting material and enhancing the short-term strength is achieved. The results of the examples show that the final setting time of the cement-based grouting material provided by the present invention is 6 to 45 minutes, and the setting time is short; at the same time, the compressive strength is 10.3 to 22.5 MPa at 2 hours and 35.3 to 36.2 MPa at 1 day, and it has a high short-term compressive strength. DETAILED DESCRIPTION

[0021] The invention provides a cement-based grouting material, comprising independently packaged modified cement-based slurry and admixture slurry; the modified cement-based slurry comprises cement, a water reducer and water; the admixture slurry comprises a coagulant, a water reducer and water.

[0022] In the present invention, the modified cement-based slurry comprises cement, a water reducer, and water. The cement is preferably ordinary Portland cement. The cement is preferably graded as 42.5, 42.5R, or 52.5. In the embodiments of the present invention, ordinary Portland cement 42.5 is specifically used, sourced from the official Jinyu Jidong Cement website.

[0023] In the present invention, the water reducer in the modified cement-based slurry is preferably a polycarboxylate water reducer; more preferably, the polycarboxylate water reducer is a Sika high-performance water reducer. In the present invention, the Sika high-performance water reducer is preferably one of 540P, 530P, and 556P. In the embodiments of the present invention, Sika high-performance water reducer 540P is specifically used, which is sourced from Sika China Co., Ltd.

[0024] In the present invention, the water in the modified cement-based slurry is preferably ordinary tap water.

[0025] In the present invention, the mass ratio of cement, water-reducing agent, and water in the modified cement-based slurry is preferably 100:0.33 to 1:20-40, and more preferably 100:0.6:25. In the present invention, controlling the mass ratio of cement, water-reducing agent, and water in the modified cement-based slurry within the above range has the effect of controlling the fluidity of the slurry, ensuring that the modified cement-based slurry is injectable within 30 minutes.

[0026] In the present invention, the admixture slurry comprises a binder, a water reducer and water. In the present invention, the binder is preferably SC-one binder; more preferably, the SC-one binder is electrochemical binder SC-one, which is sourced from Nanjing Yaojie Energy Saving Technology Co., Ltd.

[0027] In the present invention, the mass ratio of the agglomerating agent, the water reducing agent, and the water in the admixture slurry is preferably 100:0.2-0.5:33-40. In the present invention, controlling the mass ratio of the agglomerating agent, the water reducing agent, and the water in the admixture slurry within the above range has the effect of controlling the fluidity of the admixture slurry, ensuring that the admixture slurry can be injected within 30 minutes.

[0028] In the present invention, the optional range of the water reducer and water in the admixture slurry is preferably the same as the optional range of the water reducer and water in the modified cement-based slurry, which will not be repeated here.

[0029] In the present invention, the admixture slurry preferably also includes a retarder. In the present invention, the retarder is preferably one of SC-one special retarder, tartaric acid, and sodium citrate, and more preferably SC-one special retarder; in the embodiment of the present invention, SC-one special retarder D200 is specifically used, which is sourced from Beijing Yaojie Energy Saving Technology Co., Ltd. In the present invention, the function of the retarder is to adjust the setting time after the admixture slurry is mixed with the modified cement-based slurry, so as to achieve final setting of the material within 1.5 hours without pipe clogging.

[0030] In the present invention, the mass of the retarder is preferably no more than 0.35% of the mass of the agglomerator in the admixture slurry, and more preferably 0.3 to 0.35%.

[0031] In the present invention, the mass ratio of the modified cement-based slurry to the admixture slurry is preferably 3.6 to 4:1, more preferably 3.8:1. In the present invention, by controlling the mass ratio of the modified cement-based slurry to the admixture slurry within the above range, the final setting time and compressive strength of the cement-based grouting material obtained after mixing the admixture slurry with the cement slurry are adjusted.

[0032] The present invention also provides the use of the cement-based grouting material described in the above technical solution in treating diseases in operating subway tunnels.

[0033] The present invention also provides a grouting method, comprising the following steps:

[0034] The double-liquid grouting method is used to grout the depleted area with the modified cement-based slurry and admixture slurry in the cement-based grouting material of the above technical solution.

[0035] In the present invention, the void areas preferably include voids in the trackbed of the track area, voids in the non-track area, voids behind the secondary lining of the track area, and voids behind the secondary lining of the non-track area.

[0036] In the present invention, the dual-liquid grouting method preferably employs a dual-cylinder dual-liquid grouting pump equipped with a dual-liquid ratio adjustment device. The dual-cylinder dual-liquid grouting pump has two suction and discharge ports, one of which is equipped with a slurry flow ratio adjustment device. The slurry flow ratio adjustment device is preferably installed in the slurry tank containing the regulated admixture slurry. In the present invention, dual-liquid grouting employs a modified cement-based slurry and an admixture slurry to prevent premature mixing and coagulation of the slurry in the slurry storage tank, which could cause clogging of the grouting machine.

[0037] In the present invention, the model of the double-cylinder double-liquid grouting pump is preferably ZKSY70-90 double-liquid grouting machine, which comes from Zhengzhou Zhongke Support Machinery Equipment Co., Ltd.

[0038] In order to further illustrate the present invention, the cement-based grouting material provided by the present invention is described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0039] The sources of the raw materials and devices used in the following examples and comparative examples of the present invention are as follows:

[0040] Ordinary Portland cement: Jinyujidong Ordinary Portland Cement 42.5, from Jinyujidong Cement official mall.

[0041] Water reducer: Sika high-performance water reducer 540P, sourced from Sika China Co., Ltd.

[0042] Aggregate: Electrochemical aggregator SC-one, from Nanjing Yaojie Energy Saving Technology Co., Ltd.

[0043] Retarder: SC-one special retarder D200, from Beijing Yaojie Energy Saving Technology Co., Ltd.

[0044] Rapid hardening cement: Rapid hardening cement 42.5, sourced from Tangshan Polar Bear Building Materials Co., Ltd.

[0045] Hua Qiansu: HQS-Super Hua Qiansu, comes from Sichuan Hua Qiansu Building Materials Co., Ltd.

[0046] Support grouting material: CGM general-purpose high-strength non-shrinkage grouting material (cement-based), sourced from Beijing Ruishengte Building Materials Co., Ltd.

[0047] Water glass: Sourced from Bangzhiwen Industrial Products, the water glass modulus is 2.6-2.8 and the Baume degree is 50°Bé.

[0048] Example 1

[0049] Weigh 2000 g of ordinary Portland cement, 12 g of water reducer, and 800 g of water, and stir and mix at 18-22° C. for 3-5 min to obtain 2512 g of modified cement-based slurry;

[0050] Weigh 500g of agglomerating agent, 1g of water reducer and 165g of water, stir and mix at 18-22°C for 3-5min to obtain 701g of admixture slurry;

[0051] Place 2512g of modified cement-based slurry and 701g of admixture slurry in a double-cylinder double-liquid grouting pump equipped with a grouting double-liquid ratio regulating device, and adjust the flow rate of the admixture slurry to 2m 3 / h, and control the slurry volume ratio of modified cement-based slurry and admixture slurry to be 1:0.28 for grouting. After grouting, pour the slurry into the mold and cure it under standard curing conditions to obtain a standard component for strength testing.

[0052] Example 2

[0053] Weigh 2000 g of ordinary Portland cement, 20 g of water reducer, and 800 g of water, and stir and mix at 18-22° C. for 3-5 min to obtain 2520 g of modified cement-based slurry;

[0054] Weigh 500g of agglomerating agent, 2.5g of water reducer and 165g of water, stir and mix at 18-22°C for 3-5min to obtain 667.5g of admixture slurry;

[0055] 2520g of modified cement-based slurry and 667.5g of admixture slurry were placed in a double-cylinder double-liquid grouting pump with a grouting double-liquid ratio regulating device. The flow rate of the admixture slurry was adjusted to 2m3 by the slurry ratio regulating device. 3 / h, and control the slurry volume ratio of modified cement-based slurry and admixture slurry to be 1:0.26 for grouting. After grouting, pour the slurry into the mold and cure it under standard curing conditions to obtain a standard component for strength testing.

[0056] Example 3

[0057] Weigh 2000 g of ordinary Portland cement, 6.6 g of water reducer, and 800 g of water, and stir and mix at 18-22° C. for 3-5 minutes to obtain 2506.6 g of modified cement-based slurry;

[0058] Weigh 440 g of agglomerating agent, 1.6 g of water reducer, 0.44 g of retarder and 176 g of water, and stir and mix at 18-22°C for 3-5 minutes to obtain 618.04 g of admixture slurry;

[0059] 2506.6g of modified cement-based slurry and 618.04g of admixture slurry were placed in a double-cylinder double-liquid grouting pump with a grouting double-liquid ratio regulating device. The flow rate of the admixture slurry was adjusted to 2m3 by the slurry ratio regulating device. 3 / h, and control the slurry volume ratio of modified cement-based slurry and admixture slurry to be 1:0.25 for grouting. After grouting, pour the slurry into the mold and cure it under standard curing conditions to obtain a standard component for strength testing.

[0060] Comparative Example 1

[0061] Weigh 1500g of rapid-hardening cement, 4.5g of water reducer, 45g of Huaqiansu and 450g of water, stir and mix at 18-22°C for 3-5min to obtain 1999.5g of modified cement-based slurry, and use a single-liquid grouting machine for grouting.

[0062] Comparative Example 2

[0063] Weigh 1000 g of bearing grouting material and 130 g of water, stir and mix at 18-22° C. for 3-5 minutes to obtain 1130 g of grouting material, and use a single-liquid grouting machine for grouting.

[0064] Comparative Example 3

[0065] Weigh 1000 g of ordinary Portland cement, 5 g of water reducer, and 500 g of water, and stir and mix at 18-22° C. for 3-5 min to obtain 1505 g of modified cement-based slurry;

[0066] Weigh 1000g of water glass and 610g of water, stir and mix at 18-22°C for 3-5min to obtain 1610g of admixture slurry;

[0067] Place 1505g of modified cement-based slurry and 1505g of admixture slurry in a double-cylinder double-liquid grouting pump equipped with a grouting double-liquid ratio regulating device, and adjust the flow rate of the admixture slurry to 2m 3 / h, and control the slurry volume ratio of modified cement-based slurry and admixture slurry to be 1:1 for grouting. After grouting, pour the slurry into the mold and cure it under standard curing conditions to obtain a standard component for strength testing.

[0068] Test Case

[0069] The initial setting time, final setting time and compressive strength of the slurries prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were tested. Specifically, the setting time of the slurries was measured using a Vicat apparatus; the compressive strength of the test blocks was measured using a tension-compression integrated testing instrument. The results are shown in Table 1.

[0070] Table 1 Setting time, 2h and 1d compressive strength results of the grouting materials of Examples 1 to 3 and Comparative Examples 1 to 3

[0071]

[0072] Note: The "no strength" refers to the grouting material not being completely set and unable to measure the strength;

[0073] As can be seen from Table 1, the final setting time of the cement-based grouting material provided by the present invention is 6 to 45 minutes, the compressive strength is 10.3 to 22.5 MPa at 2 hours, and the compressive strength is 35.3 to 36.2 MPa at 1 day, which has the effects of short final setting time and high short-term compressive strength.

[0074] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A cement-based grouting material, comprising independently packaged modified cement-based slurry and admixture slurry; The modified cement-based slurry is composed of cement, a water reducing agent and water; the mass ratio of cement, a water reducing agent and water in the modified cement-based slurry is 100:0.33-1:20-40; the cement is ordinary Portland cement; The admixture slurry is composed of agglomerating agent, water reducing agent and water; the mass ratio of agglomerating agent, water reducing agent and water in the admixture slurry is 100:0.2-0.5:33-40.

2. The cement-based grouting material according to claim 1, characterized in that: The mass ratio of the modified cement-based slurry to the admixture slurry is 1:0.35-0.

4.

3. The cement-based grouting material according to claim 1, characterized in that: The water reducing agent in the modified cement-based slurry and the admixture slurry is a polycarboxylate water reducing agent.

4. The cement-based grouting material according to claim 1, characterized in that: The agglomerating agent is SC-one agglomerating agent.

5. Use of the cement-based grouting material according to any one of claims 1 to 4 in treating diseases of operating subway tunnels.

6. A grouting method comprising the following steps: The double-liquid grouting method is used to grout the de-voided area with the modified cement-based grout and the admixture grout in the cement-based grouting material according to any one of claims 1 to 4.

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