Mining high-strength quick-setting cement grouting material and preparation method thereof

Abstract

The invention discloses a mining high-strength quick-setting cement grouting material and a preparation method thereof, and belongs to the technical field of mining first-aid repair materials, and the mining high-strength quick-setting cement grouting material is characterized by being composed of a material A and a material B, the material A is prepared from the following raw materials in parts by weight: 100 parts of sulphoaluminate cement clinker, 1.3 to 1.7 parts of building instant glue powder, 1.8 to 2.0 parts of a water reducing agent, 10 to 20 parts of glass beads, 2.2 to 2.8 parts of a strength agent and 0.1 to 0.3 part of tartaric acid; the material B comprises the following raw materials in parts by weight: 40-78 parts of aluminate cement, 3-5 parts of calcium oxide, 0.2-0.7 part of a defoaming agent, 25-45 parts of gypsum and 1.1-1.5 parts of an early strength agent, by optimizing and selecting the components in the material A and the material B, the initial setting time of the cement grouting material is shortened, and the compressive strength within one hour reaches 30 MPa or above.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mine repair materials, in particular to a mine high-strength rapid-setting cement grouting material and a preparation method thereof. BACKGROUND

[0002] The high-strength rapid-setting cement grouting material is a special type of grouting material, which combines high strength and rapid setting and hardening. The grouting material has the characteristics of high fluidity, rapid setting and high early strength, and can reach the design strength in a short time to ensure the rapid stability of the structure. Therefore, the rapid-setting grouting material can be applied to mine safety protection reinforcement, underground tunnel and building wall solidification engineering, and has a wide application in the mining resource development and construction industry, especially in the engineering requiring rapid hardening. The rapid-setting grouting material has low cost, short construction period, high efficiency and significant economic benefits.

[0003] The existing rapid-setting grouting material has a slow initial setting speed, usually 2-5h, and low strength during initial setting, usually 15MPa in 1h. The commercially available high-strength rapid-setting material (the grouting material reaching 30MPa in 1 day is high-strength rapid-setting material) is 20MPa in 1h, which is far from meeting the use requirements in harsh environments. SUMMARY

[0004] In order to solve the problems in the prior art, the present application provides a mine high-strength rapid-setting cement grouting material and a preparation method thereof. By optimizing the components in A material and B material, the initial setting time of the cement grouting material is shortened, and the compressive strength in 1h reaches more than 30MPa.

[0005] The first aspect of the present application is to provide a mine high-strength rapid-setting cement grouting material, which adopts the following technical scheme: A mine high-strength rapid-setting cement grouting material is composed of A material and B material. The A material includes the following raw materials in parts by weight: sulphoaluminate cement clinker 100 parts, building instant glue powder 1.3-1.7 parts, water reducing agent 1.8-2.0 parts, glass microbeads 10-20 parts, strength agent 2.2-2.8 parts, and tartaric acid 0.1-0.3 parts. The B material includes the following raw materials in parts by weight: aluminate cement 40-78 parts, calcium oxide 3-5 parts, defoaming agent 0.2-0.7 parts, gypsum 25-45 parts, and early strength agent 1.1-1.5 parts.

[0006] By adopting the technical scheme, the A material and the B material are mixed, and then the synergistic effect of the sulphoaluminate-aluminate double gel system is achieved, so that the balanced performance of rapid setting, high strength, micro-expansion and high durability is realized. The reason may be that the sulphoaluminate cement clinker in the A material has a fast hydration speed, can provide instant strength, the gypsum in the B material reacts with the aluminate cement to generate ettringite, further accelerates setting, and the process of generating ettringite produces an expansion effect, which can compensate for the hardening shrinkage, and the calcium oxide provides an alkaline environment for cement hydration and participates in hydration, promotes the formation of C-S-H gel, and enhances the early strength of the grouting material. Therefore, after the A material and the B material are mixed, the setting time is further shortened, and the strength of the grouting material can reach 30 MPa in one hour, which can effectively meet the needs in special situations (such as rescue, reinforcement of mine tunnels, bridges, etc.). In order to avoid the flash setting of the A material and the B material after mixing, tartaric acid is added to the A material, so as to ensure the operability of construction.

[0007] In addition, the building instant gel powder in the A material can improve the fluidity, prevent bleeding and segregation, and effectively ensure the construction performance of the grouting material.

[0008] In a preferred embodiment, the weight ratio of the A material to the B material is (1.17-1.26): 1.

[0009] By adopting the technical scheme, when the A material and the B material are mixed according to the weight ratio, the strength of the grouting material can be ensured, and the grouting material can also be quickly set.

[0010] In a preferred embodiment, the strength agent in the A material includes one or both of an anhydrous sodium sulfate and bauxite.

[0011] In a preferred embodiment, the weight ratio of the anhydrous sodium sulfate to the bauxite is (1.4-1.6): 1.

[0012] By adopting the technical scheme, when the strength agent is composed of the anhydrous sodium sulfate and the bauxite, the bauxite promotes the reaction of the anhydrous sodium sulfate and the aluminate tricalcium in the cement to generate ettringite, accelerates the early cement hydration, and improves the early strength of the cement grouting material.

[0013] In a preferred embodiment, the strength agent in the B material is one or both of calcium formate and lithium carbonate.

[0014] By adopting the technical scheme, lithium carbonate in the early strength agent reacts with aluminate minerals in the cement to generate monocarbon hydroxycarbon aluminate, which helps to increase the solid phase volume in the cement slurry, reduce the porosity of the cement slurry, and improve the compactness at the same hydration degree. Moreover, lithium carbonate can significantly accelerate the hydration rate of the cementitious material and improve the strength at a lower dosage. In addition, due to the small radius of lithium ions, lithium ions have strong polarization effect and can accelerate the destruction of the hydration protection film on the surface of the cement particles, thereby significantly shortening the induction period of cement hydration.

[0015] Calcium formate can significantly accelerate the hydration reaction process of the cement. After the cement is mixed with water, calcium ions in the calcium formate can react with mineral components such as tricalcium silicate and dicalcium silicate in the cement to promote the dissolution of the cement minerals and the formation of hydration products, so that the cement slurry can reach a high strength in a short time, the setting time of the cement is shortened, and the strength of the cement slurry is improved.

[0016] In a preferred embodiment, the addition amount of lithium carbonate is 10% by weight of calcium formate.

[0017] In a preferred embodiment, 0.01-0.03 parts by weight of hydroxypropyl starch ether is further added to the B material.

[0018] By adopting the technical scheme, after the hydroxypropyl starch ether is added to the B material, the hydroxypropyl starch ether can form strong adhesion with the cement hydration products, thereby improving the bonding strength and strength of the cement grouting material.

[0019] In a preferred embodiment, the particle size of the glass beads is 200 mesh.

[0020] The second aspect of the present application is to provide a preparation method of the mine high-strength rapid-setting cement grouting material as described above, comprising the following steps: preparing A material, uniformly mixing sulfaluminate cement clinker, building instant glue powder, water reducing agent, glass beads, strength agent, and tartaric acid according to weight parts, adding water, and stirring for 1-2 min; Preparing B material, uniformly mixing aluminate cement, calcium oxide, defoaming agent, gypsum, and early strength agent according to weight parts, adding water, stirring for 1-2 min, and then mixing the A material and the B material to obtain the cement grouting material.

[0021] By adopting the technical scheme, the A material and the B material are separately prepared and then mixed with water, so that uniform mixing of the substances and no interference between the substances can be ensured, and the strength obtained by mixing after separately adding water is superior to the strength obtained by mixing the A and B powders and then adding water, because, after water is first added to the A and B materials, the sulphoaluminate cement clinker in the A material first forms C-S-H gel and a small amount of ettringite, and the structure is more uniform, and the aluminate cement in the B material reacts with the gypsum to form ettringite, so that, when the pre-activated A and B materials are mixed, the remaining active components react more gently and the hydration products are more uniformly distributed, while, when the two powders are mixed and then water is added, the sulphoaluminate cement clinker and the aluminate cement directly contact each other, and the active components of the two cements directly react at the moment of adding water, a large amount of ettringite and aluminum gel are generated, the hydration heat is concentratedly released, a temperature gradient is formed, micro-cracks are induced, a large amount of ettringite is locally accumulated, the subsequent hydration channels are hindered, the completeness of cement hydration is affected, and the strength of the cement grouting material is greatly reduced, the strength at 1 hour is at most 24 MPa, therefore, by separately mixing the A and B powders and adding water, the pre-activation of the A material and the B material can be ensured, and the initial setting time of the cement grouting material can be effectively shortened and the compressive strength at 1 hour can be improved.

[0022] In a preferred embodiment, the water-binder ratios of the A material and the B material are both 0.25.

[0023] In summary, the application has the following beneficial effects: 1. By the synergistic effect of the sulphoaluminate-aluminate double gel system, the application realizes balanced performance of rapid setting, high strength, micro-expansion and high durability, and can effectively meet the strength requirements in special situations.

[0024] 2. In the application, the cooperation between the strength agent and the early strength agent not only effectively improves the compressive strength of the cement grouting material at 1 hour, but also effectively shortens the initial setting time of the cement grouting material. DETAILED DESCRIPTION

[0025] The application will be further described in detail below in combination with examples. All reagents not specified by the manufacturer are conventional reagent products that can be obtained by purchase on the market.

[0026] In a preferred embodiment, a mine high-strength rapid-setting cement grouting material is composed of an A material and a B material. The A material includes the following raw materials in parts by weight: sulphoaluminate cement clinker 100 parts, building instant glue powder 1.3-1.7 parts, water reducing agent 1.8-2.0 parts, glass microbeads 10-20 parts, strength agent 2.2-2.8 parts, and tartaric acid 0.1-0.3 parts. The B material comprises the following raw materials by weight: aluminate cement 40-78 parts, calcium oxide 3-5 parts, defoaming agent 0.2-0.7 parts, gypsum 25-45 parts, early strength agent 1.1-1.5 parts.

[0027] In a preferred embodiment, the weight ratio of the A material and the B material is (1.17-1.26):1.

[0028] In a preferred embodiment, the strength agent in the A material comprises one or both of an alumina and bauxite.

[0029] In a preferred embodiment, the weight ratio of the alumina and the bauxite is (1.4-1.6):1.

[0030] In a preferred embodiment, the strength agent in the B material is one or both of calcium formate and lithium carbonate.

[0031] In a preferred embodiment, the amount of lithium carbonate added is 10% by weight of the calcium formate.

[0032] In a preferred embodiment, 0.01-0.03 parts by weight of hydroxypropyl starch ether is further added to the B material.

[0033] In a preferred embodiment, the particle size of the glass beads is 200 mesh.

[0034] A second aspect of the present application is to provide a preparation method of the mine high-strength rapid-setting cement grouting material as described above, comprising the following steps: preparing the A material, mixing the sulphoaluminate cement clinker, the building instant glue powder, the water reducing agent, the glass beads, the strength agent and the tartaric acid uniformly according to the weight parts, adding water, and stirring for 1-2 min; Preparing the B material, mixing the aluminate cement, the calcium oxide, the defoaming agent, the gypsum and the early strength agent uniformly according to the weight parts, adding water, stirring for 1-2 min, and mixing the A material and the B material to obtain the cement grouting material.

[0035] In a preferred embodiment, the water-binder ratio of the A material and the B material is 0.25.

[0036] In the examples and comparative examples of the present application, the water reducing agent is a polycarboxylic high-performance water reducing agent, and the water reduction rate is 20%. Example 1

[0037] A preparation method of a mine high-strength rapid-setting cement grouting material, comprising the following steps: The A material is prepared by uniformly mixing 10 kg of sulphoaluminate cement clinker, 0.13 kg of building instant glue powder, 0.18 kg of water reducing agent, 1 kg of glass beads with a particle size of 200 mesh, 0.22 kg of strength agent and 0.01 kg of tartaric acid; wherein the strength agent is composed of anhydrous sodium sulphate and bauxite in a weight ratio of 1.4:1; The B material is prepared by uniformly mixing 4 kg of aluminate cement, 0.3 kg of calcium oxide, 0.02 kg of silicone defoaming agent, 2.5 kg of gypsum and 0.11 kg of early strength agent; wherein the early strength agent is composed of lithium carbonate and calcium formate, and the addition amount of lithium carbonate is 10% of the weight of calcium formate; The A material and the B material are prepared in a weight ratio of 1.17:1, and then water is added to the A material and the B material respectively, and the water-binder ratio is 0.25; the A material and the B material are stirred for 1-2 min respectively, and then the A material and the B material are mixed and stirred to obtain the cement grouting material.

[0038] Example 2

[0039] A preparation method of a mine high-strength quick-setting cement grouting material, comprising the following steps: The A material is prepared by uniformly mixing 10 kg of sulphoaluminate cement clinker, 0.15 kg of building instant glue powder, 0.19 kg of water reducing agent, 1.5 kg of glass beads with a particle size of 200 mesh, 0.25 kg of strength agent and 0.02 kg of tartaric acid; wherein the strength agent is composed of anhydrous sodium sulphate and bauxite in a weight ratio of 1.5:1; The B material is prepared by uniformly mixing 5.6 kg of aluminate cement, 0.4 kg of calcium oxide, 0.05 kg of silicone defoaming agent, 3.5 kg of gypsum and 0.13 kg of early strength agent; wherein the early strength agent is composed of lithium carbonate and calcium formate, and the addition amount of lithium carbonate is 10% of the weight of calcium formate; The A material and the B material are prepared in a weight ratio of 1.17:1, and then water is added to the A material and the B material respectively, and the water-binder ratio is 0.25; the A material and the B material are stirred for 1-2 min respectively, and then the A material and the B material are mixed and stirred to obtain the cement grouting material.

[0040] Example 3

[0041] A preparation method of a mine high-strength quick-setting cement grouting material, comprising the following steps: The A material is prepared by uniformly mixing 10 kg of sulphoaluminate cement clinker, 0.17 kg of building instant glue powder, 0.2 kg of water reducing agent, 2 kg of glass beads with a particle size of 200 mesh, 0.28 kg of strength agent and 0.03 kg of tartaric acid; wherein the strength agent is composed of anhydrous sodium sulphate and bauxite in a weight ratio of 1.6:1; The B material is prepared by mixing aluminate cement 7.8 kg, calcium oxide 0.5 kg, silicone defoaming agent 0.07 kg, gypsum 4.5 kg and early strength agent 0.15 kg uniformly, wherein the early strength agent is composed of lithium carbonate and calcium formate, and the addition amount of lithium carbonate is 10% of the weight of calcium formate; The A material and the B material are prepared according to a weight ratio of 1.17:1, then water is added into the A material and the B material respectively, and the water-binder ratios are both 0.25, the A material and the B material are stirred for 1-2 min respectively, then the A material and the B material are mixed and stirred to obtain the cement grouting material.

[0042] Example 4

[0043] A preparation method of a mine-used high-strength rapid-setting cement grouting material, which is different from example 2 in that the A material and the B material are mixed according to a weight ratio of 1.26:1, and the others are the same as example 2.

[0044] Example 5

[0045] A preparation method of a mine-used high-strength rapid-setting cement grouting material, which is different from example 2 in that the B material further contains hydroxypropyl starch ether 0.001 kg, and the others are the same as example 2.

[0046] Example 6

[0047] A preparation method of a mine-used high-strength rapid-setting cement grouting material, which is different from example 2 in that the B material further contains hydroxypropyl starch ether 0.003 kg, and the others are the same as example 2.

[0048] Example 7

[0049] A preparation method of a mine-used high-strength rapid-setting cement grouting material, which is different from example 2 in that the strength agent in the A material only uses anhydrous sodium sulfate, and the others are the same as example 2.

[0050] Example 8

[0051] A preparation method of a mine-used high-strength rapid-setting cement grouting material, which is different from example 2 in that the strength agent in the A material only uses bauxite, and the others are the same as example 2.

[0052] Example 9

[0053] A preparation method of a mine-used high-strength rapid-setting cement grouting material, which is different from example 2 in that the early strength agent in the B material only uses calcium formate, and the others are the same as example 2.

[0054] Example 10

[0055] A preparation method of a mine high-strength rapid-setting cement grouting material, which is different from example 2 in that only lithium carbonate is used as the early strength agent in the B material, and the others are the same as in example 2.

[0056] Comparative example 1 A preparation method of a mine high-strength rapid-setting cement grouting material, which is different from example 2 in that the strength agent is missing in the A material, and the others are the same as in example 2.

[0057] Comparative example 2 A preparation method of a mine high-strength rapid-setting cement grouting material, which is different from example 2 in that the early strength agent is missing in the B material, and the others are the same as in example 2.

[0058] Performance detection The cement grouting materials obtained in the above examples and comparative examples were tested for setting time and compressive strength, and the test results are shown in Table 1, wherein the compressive strength was tested in accordance with the relevant provisions in GB / T 50448-2015 “Technical Code for Cement-based Grouting”.

[0059] Table 1: Test results of cement grouting materials Item Initial setting time / min 1 hour compressive strength / MPa 1 day compressive strength / MPa Example 1 3.5 31.2 54.9 Example 2 3.2 33.5 55.8 Example 3 3.1 32.6 55.7 Example 4 3.8 31.8 55.2 Example 5 3.2 35.8 56.3 Example 6 3.3 35.5 56.2 Example 7 4.6 28.6 54.3 Example 8 4.7 29.2 54.1 Example 9 6.5 27.4 53.2 Example 10 5.9 28.2 53.8 Comparative Example 1 8.2 23.6 48.6 Comparative Example 2 9.5 21.3 47.2 As can be seen from Table 1 above: The initial setting time of the cement grouting materials obtained in examples 1-4 is within 4 minutes, and the 1-hour compressive strength is all above 30 MPa, indicating that the cement grouting materials obtained in the present application can achieve rapid setting and high strength, thereby meeting the use requirements in harsh environments.

[0060] Compared with example 2, when hydroxypropyl starch ether is added to the cement grouting material, the initial setting time of the cement grouting material obtained in examples 5-6 is slightly shorter than that of example 2, and the 1-hour compressive strength is significantly higher than that of example 2, indicating that the addition of hydroxypropyl starch ether can further enhance the early strength of the cement grouting material.

[0061] Compared with example 2, when the strength agent only uses sodium sulfate or bauxite, the initial setting time of the cement grouting material obtained in examples 7-8 is significantly increased compared with example 2, and the 1-hour strength of the cement grouting material is significantly reduced compared with example 2, indicating that when the strength agent only uses one of sodium sulfate or bauxite, the amount of ettringite generated in the grouting material is reduced, thereby reducing the strength of the cement grouting material, and also prolonging the cement hydration time, resulting in an extended initial setting time.

[0062] Compared with Example 2, the initial setting time of the cement grout obtained in Examples 9-10 is obviously increased, and the 1-hour compressive strength is obviously decreased, when only calcium formate or lithium carbonate is used as the early strength agent, because both lithium carbonate and calcium formate can promote the hydration of cement, thereby shortening the setting time of the cement grout. Therefore, when only calcium formate or lithium carbonate is used, the setting time is prolonged and the compressive strength is decreased in Examples 9-10.

[0063] Compared with Example 2, the initial setting time of the cement grout obtained in Comparative Examples 1-2 is much longer, and the 1-hour compressive strength is much lower, when the strength agent and the early strength agent are both absent from the cement grout, which indicates that the use of the strength agent and the early strength agent not only improves the compressive strength of the cement grout, but also greatly shortens the setting time of the cement grout, thereby effectively meeting the use requirements of the cement grout in harsh environments.

[0064] The embodiments of the specific implementation are the preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A high-strength, quick-setting cement grout for mining, characterized in that: Composed of material A and material B; Material A comprises the following raw materials in parts by weight: 100 parts of sulfoaluminate cement clinker, 1.3-1.7 parts of quick-dissolving building adhesive powder, 1.8-2.0 parts of water-reducing agent, 10-20 parts of glass microspheres, 2.2-2.8 parts of strength agent, and 0.1-0.3 parts of tartaric acid; Material B comprises the following raw materials in parts by weight: 40-78 parts aluminate cement, 3-5 parts calcium oxide, 0.2-0.7 parts defoamer, 25-45 parts gypsum, and 1.1-1.5 parts early strength agent.

2. The high-strength, quick-setting cement grouting material for mining according to claim 1, characterized in that: The weight ratio of material A to material B is (1.17-1.26):

1.

3. The high-strength, quick-setting cement grouting material for mining according to claim 1, characterized in that: The strength agent in material A includes one or both of sodium sulfate and bauxite.

4. The high-strength, quick-setting cement grouting material for mining according to claim 3, characterized in that: The weight ratio of sodium sulfate to bauxite is (1.4-1.6):

1.

5. The high-strength, quick-setting cement grouting material for mining according to claim 1, characterized in that: The strength agent in material B is one or both of calcium formate and lithium carbonate.

6. The high-strength, quick-setting cement grouting material for mining according to claim 5, characterized in that: The amount of lithium carbonate added is 10% of the weight of calcium formate.

7. The high-strength, quick-setting cement grouting material for mining according to claim 1, characterized in that: The B component also contains 0.01-0.03 parts by weight of hydroxypropyl starch ether.

8. The high-strength, quick-setting cement grouting material for mining according to claim 1, characterized in that: The glass microspheres have a particle size of 200 mesh.

9. A method for preparing a high-strength, quick-setting cement grout for mining as described in any one of claims 1-8, characterized in that, The process includes the following steps: Prepare material A by mixing sulfoaluminate cement clinker, quick-dissolving building adhesive powder, water-reducing agent, glass microspheres, strength agent and tartaric acid according to the weight parts, then add water and stir for 1-2 minutes. To prepare component B, mix aluminate cement, calcium oxide, defoamer, gypsum, and early strength agent evenly according to their weight proportions, add water, stir for 1-2 minutes, and then mix component A and component B to obtain cement grouting material.

10. The method for preparing a high-strength, quick-setting cement grout for mining according to claim 9, characterized in that: The water-to-binder ratio of both component A and component B is 0.25.